Adding upstream version 2.10.36.upstream/2.10.36

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2278 insertions, 0 deletions

diff --git a/plug-ins/file-dds/ddswrite.c b/plug-ins/file-dds/ddswrite.c
new file mode 100644
index 0000000..5fb658a
--- /dev/null
+++ b/plug-ins/file-dds/ddswrite.c
@@ -0,0 +1,2278 @@
+/*
+ * DDS GIMP plugin
+ *
+ * Copyright (C) 2004-2012 Shawn Kirst <skirst@gmail.com>,
+ * with parts (C) 2003 Arne Reuter <homepage@arnereuter.de> where specified.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 51 Franklin Street, Fifth Floor
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include "config.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+
+#include <gtk/gtk.h>
+#include <glib/gstdio.h>
+
+#include <libgimp/gimp.h>
+#include <libgimp/gimpui.h>
+
+#include <libgimp/stdplugins-intl.h>
+
+#include "ddsplugin.h"
+#include "dds.h"
+#include "dxt.h"
+#include "mipmap.h"
+#include "endian_rw.h"
+#include "imath.h"
+#include "color.h"
+
+
+enum
+{
+  COMBO_VALUE,
+  COMBO_STRING,
+  COMBO_SENSITIVE
+};
+
+
+static gint       save_dialog          (gint32     image_id,
+                                        gint32     drawable);
+static void       save_dialog_response (GtkWidget *widget,
+                                        gint       response_id,
+                                        gpointer   data);
+static gboolean   write_image          (FILE      *fp,
+                                        gint32     image_id,
+                                        gint32     drawable_id);
+
+
+static gboolean runme = FALSE;
+
+static const char *cubemap_face_names[4][6] =
+{
+  {
+    "positive x", "negative x",
+    "positive y", "negative y",
+    "positive z", "negative z"
+  },
+  {
+    "pos x", "neg x",
+    "pos y", "neg y",
+    "pos z", "neg z",
+  },
+  {
+    "+x", "-x",
+    "+y", "-y",
+    "+z", "-z"
+  },
+  {
+    "right", "left",
+    "top", "bottom",
+    "back", "front"
+  }
+};
+
+static gint     cubemap_faces[6];
+static gboolean is_cubemap            = FALSE;
+static gboolean is_volume             = FALSE;
+static gboolean is_array              = FALSE;
+static gboolean is_mipmap_chain_valid = FALSE;
+
+static GtkWidget *compress_opt;
+static GtkWidget *format_opt;
+static GtkWidget *mipmap_opt;
+static GtkWidget *mipmap_filter_opt;
+static GtkWidget *mipmap_wrap_opt;
+static GtkWidget *srgb_chk;
+static GtkWidget *gamma_chk;
+static GtkWidget *gamma_spin;
+static GtkWidget *pm_chk;
+static GtkWidget *alpha_coverage_chk;
+static GtkWidget *alpha_test_threshold_spin;
+
+typedef struct string_value_s
+{
+  gint   value;
+  gchar *string;
+} string_value_t;
+
+static string_value_t compression_strings[] =
+{
+  { DDS_COMPRESS_NONE,   "None" },
+  { DDS_COMPRESS_BC1,    "BC1 / DXT1" },
+  { DDS_COMPRESS_BC2,    "BC2 / DXT3" },
+  { DDS_COMPRESS_BC3,    "BC3 / DXT5" },
+  { DDS_COMPRESS_BC3N,   "BC3nm / DXT5nm" },
+  { DDS_COMPRESS_BC4,    "BC4 / ATI1 (3Dc+)" },
+  { DDS_COMPRESS_BC5,    "BC5 / ATI2 (3Dc)" },
+  { DDS_COMPRESS_RXGB,   "RXGB (DXT5)" },
+  { DDS_COMPRESS_AEXP,   "Alpha Exponent (DXT5)" },
+  { DDS_COMPRESS_YCOCG,  "YCoCg (DXT5)" },
+  { DDS_COMPRESS_YCOCGS, "YCoCg scaled (DXT5)" },
+  { -1, 0}
+};
+
+static string_value_t format_strings[] =
+{
+  { DDS_FORMAT_DEFAULT, "Default" },
+  { DDS_FORMAT_RGB8,    "RGB8" },
+  { DDS_FORMAT_RGBA8,   "RGBA8" },
+  { DDS_FORMAT_BGR8,    "BGR8" },
+  { DDS_FORMAT_ABGR8,   "ABGR8" },
+  { DDS_FORMAT_R5G6B5,  "R5G6B5" },
+  { DDS_FORMAT_RGBA4,   "RGBA4" },
+  { DDS_FORMAT_RGB5A1,  "RGB5A1" },
+  { DDS_FORMAT_RGB10A2, "RGB10A2" },
+  { DDS_FORMAT_R3G3B2,  "R3G3B2" },
+  { DDS_FORMAT_A8,      "A8" },
+  { DDS_FORMAT_L8,      "L8" },
+  { DDS_FORMAT_L8A8,    "L8A8" },
+  { DDS_FORMAT_AEXP,    "AExp" },
+  { DDS_FORMAT_YCOCG,   "YCoCg" },
+  { -1, 0}
+};
+
+static string_value_t mipmap_strings[] =
+{
+  { DDS_MIPMAP_NONE,     "No mipmaps" },
+  { DDS_MIPMAP_GENERATE, "Generate mipmaps" },
+  { DDS_MIPMAP_EXISTING, "Use existing mipmaps" },
+  { -1, 0}
+};
+
+static string_value_t mipmap_filter_strings[] =
+{
+  { DDS_MIPMAP_FILTER_DEFAULT,   "Default" },
+  { DDS_MIPMAP_FILTER_NEAREST,   "Nearest" },
+  { DDS_MIPMAP_FILTER_BOX,       "Box" },
+  { DDS_MIPMAP_FILTER_TRIANGLE,  "Triangle" },
+  { DDS_MIPMAP_FILTER_QUADRATIC, "Quadratic" },
+  { DDS_MIPMAP_FILTER_BSPLINE,   "B-Spline" },
+  { DDS_MIPMAP_FILTER_MITCHELL,  "Mitchell" },
+  { DDS_MIPMAP_FILTER_LANCZOS,   "Lanczos" },
+  { DDS_MIPMAP_FILTER_KAISER,    "Kaiser" },
+  { -1, 0}
+};
+
+static string_value_t mipmap_wrap_strings[] =
+{
+  { DDS_MIPMAP_WRAP_DEFAULT, "Default" },
+  { DDS_MIPMAP_WRAP_MIRROR,  "Mirror" },
+  { DDS_MIPMAP_WRAP_REPEAT,  "Repeat" },
+  { DDS_MIPMAP_WRAP_CLAMP,   "Clamp" },
+  { -1, 0}
+};
+
+static string_value_t save_type_strings[] =
+{
+  { DDS_SAVE_SELECTED_LAYER, "Selected layer" },
+  { DDS_SAVE_CUBEMAP,        "As cube map" },
+  { DDS_SAVE_VOLUMEMAP,      "As volume map" },
+  { DDS_SAVE_ARRAY,          "As texture array" },
+  { DDS_SAVE_VISIBLE_LAYERS, "All visible layers" },
+  { -1, 0}
+};
+
+static struct
+{
+  int          format;
+  DXGI_FORMAT  dxgi_format;
+  int          bpp;
+  int          alpha;
+  unsigned int rmask;
+  unsigned int gmask;
+  unsigned int bmask;
+  unsigned int amask;
+} format_info[] =
+{
+  { DDS_FORMAT_RGB8,    DXGI_FORMAT_UNKNOWN,           3, 0, 0x00ff0000, 0x0000ff00, 0x000000ff, 0x00000000},
+  { DDS_FORMAT_RGBA8,   DXGI_FORMAT_B8G8R8A8_UNORM,    4, 1, 0x00ff0000, 0x0000ff00, 0x000000ff, 0xff000000},
+  { DDS_FORMAT_BGR8,    DXGI_FORMAT_UNKNOWN,           3, 0, 0x000000ff, 0x0000ff00, 0x00ff0000, 0x00000000},
+  { DDS_FORMAT_ABGR8,   DXGI_FORMAT_R8G8B8A8_UNORM,    4, 1, 0x000000ff, 0x0000ff00, 0x00ff0000, 0xff000000},
+  { DDS_FORMAT_R5G6B5,  DXGI_FORMAT_B5G6R5_UNORM,      2, 0, 0x0000f800, 0x000007e0, 0x0000001f, 0x00000000},
+  { DDS_FORMAT_RGBA4,   DXGI_FORMAT_B4G4R4A4_UNORM,    2, 1, 0x00000f00, 0x000000f0, 0x0000000f, 0x0000f000},
+  { DDS_FORMAT_RGB5A1,  DXGI_FORMAT_B5G5R5A1_UNORM,    2, 1, 0x00007c00, 0x000003e0, 0x0000001f, 0x00008000},
+  { DDS_FORMAT_RGB10A2, DXGI_FORMAT_R10G10B10A2_UNORM, 4, 1, 0x000003ff, 0x000ffc00, 0x3ff00000, 0xc0000000},
+  { DDS_FORMAT_R3G3B2,  DXGI_FORMAT_UNKNOWN,           1, 0, 0x000000e0, 0x0000001c, 0x00000003, 0x00000000},
+  { DDS_FORMAT_A8,      DXGI_FORMAT_A8_UNORM,          1, 0, 0x00000000, 0x00000000, 0x00000000, 0x000000ff},
+  { DDS_FORMAT_L8,      DXGI_FORMAT_R8_UNORM,          1, 0, 0x000000ff, 0x000000ff, 0x000000ff, 0x00000000},
+  { DDS_FORMAT_L8A8,    DXGI_FORMAT_UNKNOWN,           2, 1, 0x000000ff, 0x000000ff, 0x000000ff, 0x0000ff00},
+  { DDS_FORMAT_AEXP,    DXGI_FORMAT_B8G8R8A8_UNORM,    4, 1, 0x00ff0000, 0x0000ff00, 0x000000ff, 0xff000000},
+  { DDS_FORMAT_YCOCG,   DXGI_FORMAT_B8G8R8A8_UNORM,    4, 1, 0x00ff0000, 0x0000ff00, 0x000000ff, 0xff000000}
+};
+
+
+static gboolean
+check_mipmaps (gint32 image_id,
+               gint   savetype)
+{
+  gint *layers;
+  gint  num_layers;
+  gint  i, j, w, h, mipw, miph;
+  gint  num_mipmaps;
+  gint  num_surfaces = 0;
+  gint  min_surfaces = 1;
+  gint  max_surfaces = 1;
+  gboolean valid = TRUE;
+  GimpImageType type;
+
+  /* not handling volume maps for the moment... */
+  if (savetype == DDS_SAVE_VOLUMEMAP)
+    return 0;
+
+  if (savetype == DDS_SAVE_CUBEMAP)
+    {
+      min_surfaces = 6;
+      max_surfaces = 6;
+    }
+  else if (savetype == DDS_SAVE_ARRAY)
+    {
+      min_surfaces = 2;
+      max_surfaces = INT_MAX;
+    }
+
+  layers = gimp_image_get_layers (image_id, &num_layers);
+
+  w = gimp_image_width (image_id);
+  h = gimp_image_height (image_id);
+
+  num_mipmaps = get_num_mipmaps (w, h);
+
+  type = gimp_drawable_type (layers[0]);
+
+  for (i = 0; i < num_layers; ++i)
+    {
+      if (type != gimp_drawable_type (layers[i]))
+        return 0;
+
+      if ((gimp_drawable_width (layers[i])  == w) &&
+          (gimp_drawable_height (layers[i]) == h))
+        ++num_surfaces;
+    }
+
+  if ((num_surfaces < min_surfaces) ||
+      (num_surfaces > max_surfaces) ||
+      (num_layers != (num_surfaces * num_mipmaps)))
+    return 0;
+
+  for (i = 0; valid && i < num_layers; i += num_mipmaps)
+    {
+      if ((gimp_drawable_width (layers[i])  != w) ||
+          (gimp_drawable_height (layers[i]) != h))
+        {
+          valid = FALSE;
+          break;
+        }
+
+      for (j = 1; j < num_mipmaps; ++j)
+        {
+          mipw = w >> j;
+          miph = h >> j;
+          if (mipw < 1) mipw = 1;
+          if (miph < 1) miph = 1;
+          if ((gimp_drawable_width (layers[i + j])  != mipw) ||
+              (gimp_drawable_height (layers[i + j]) != miph))
+            {
+              valid = FALSE;
+              break;
+            }
+        }
+    }
+
+  return valid;
+}
+
+static gboolean
+check_cubemap (gint32 image_id)
+{
+  gint *layers;
+  gint  num_layers;
+  gboolean cubemap = TRUE;
+  gint i, j, k, w, h;
+  gchar *layer_name;
+  GimpImageType type;
+
+  layers = gimp_image_get_layers (image_id, &num_layers);
+
+  if (num_layers < 6)
+    return FALSE;
+
+  /* check for a valid cubemap with mipmap layers */
+  if (num_layers > 6)
+    {
+      /* check that mipmap layers are in order for a cubemap */
+      if (! check_mipmaps (image_id, DDS_SAVE_CUBEMAP))
+        return FALSE;
+
+      /* invalidate cubemap faces */
+      for (i = 0; i < 6; ++i)
+        cubemap_faces[i] = -1;
+
+      /* find the mipmap level 0 layers */
+      w = gimp_image_width (image_id);
+      h = gimp_image_height (image_id);
+
+      for (i = 0; i < num_layers; ++i)
+        {
+          if ((gimp_drawable_width (layers[i])  != w) ||
+              (gimp_drawable_height (layers[i]) != h))
+            continue;
+
+          layer_name = (char*)gimp_item_get_name (layers[i]);
+          for (j = 0; j < 6; ++j)
+            {
+              for (k = 0; k < 4; ++k)
+                {
+                  if (strstr (layer_name, cubemap_face_names[k][j]))
+                    {
+                      if (cubemap_faces[j] == -1)
+                        {
+                          cubemap_faces[j] = layers[i];
+                          break;
+                        }
+                    }
+                }
+            }
+        }
+
+      /* check for 6 valid faces */
+      for (i = 0; i < 6; ++i)
+        {
+          if (cubemap_faces[i] == -1)
+            {
+              cubemap = FALSE;
+              break;
+            }
+        }
+
+      /* make sure they are all the same type */
+      if (cubemap)
+        {
+          type = gimp_drawable_type (cubemap_faces[0]);
+          for (i = 1; i < 6 && cubemap; ++i)
+            {
+              if (gimp_drawable_type (cubemap_faces[i]) != type)
+                cubemap = FALSE;
+            }
+        }
+    }
+
+  if (num_layers == 6)
+    {
+      /* invalidate cubemap faces */
+      for (i = 0; i < 6; ++i)
+        cubemap_faces[i] = -1;
+
+      for (i = 0; i < 6; ++i)
+        {
+          layer_name = (char*)gimp_item_get_name (layers[i]);
+          for (j = 0; j < 6; ++j)
+            {
+              for (k = 0; k < 4; ++k)
+                {
+                  if (strstr (layer_name, cubemap_face_names[k][j]))
+                    {
+                      if (cubemap_faces[j] == -1)
+                        {
+                          cubemap_faces[j] = layers[i];
+                          break;
+                        }
+                    }
+                }
+            }
+        }
+
+      /* check for 6 valid faces */
+      for (i = 0; i < 6; ++i)
+        {
+          if (cubemap_faces[i] == -1)
+            {
+              cubemap = FALSE;
+              break;
+            }
+        }
+
+      /* make sure they are all the same size */
+      if (cubemap)
+        {
+          w = gimp_drawable_width (cubemap_faces[0]);
+          h = gimp_drawable_height (cubemap_faces[0]);
+
+          for (i = 1; i < 6 && cubemap; ++i)
+            {
+              if ((gimp_drawable_width (cubemap_faces[i])  != w) ||
+                  (gimp_drawable_height (cubemap_faces[i]) != h))
+                cubemap = FALSE;
+            }
+        }
+
+      /* make sure they are all the same type */
+      if (cubemap)
+        {
+          type = gimp_drawable_type (cubemap_faces[0]);
+          for (i = 1; i < 6 && cubemap; ++i)
+            {
+              if (gimp_drawable_type (cubemap_faces[i]) != type)
+                cubemap = FALSE;
+            }
+        }
+    }
+
+  return cubemap;
+}
+
+static gboolean
+check_volume (gint32 image_id)
+{
+  gint *layers;
+  gint  num_layers;
+  gboolean volume = FALSE;
+  gint i, w, h;
+  GimpImageType type;
+
+  layers = gimp_image_get_layers (image_id, &num_layers);
+
+  if (num_layers > 1)
+    {
+      volume = TRUE;
+
+      /* make sure all layers are the same size */
+      w = gimp_drawable_width (layers[0]);
+      h = gimp_drawable_height (layers[0]);
+
+      for (i = 1; i < num_layers && volume; ++i)
+        {
+          if ((gimp_drawable_width (layers[i])  != w) ||
+              (gimp_drawable_height (layers[i]) != h))
+            volume = FALSE;
+        }
+
+      if (volume)
+        {
+          /* make sure all layers are the same type */
+          type = gimp_drawable_type (layers[0]);
+          for (i = 1; i < num_layers && volume; ++i)
+            {
+              if (gimp_drawable_type (layers[i]) != type)
+                volume = FALSE;
+            }
+        }
+    }
+
+  return volume;
+}
+
+static gboolean
+check_array (gint32 image_id)
+{
+  gint *layers;
+  gint  num_layers;
+  gboolean array = FALSE;
+  gint i, w, h;
+  GimpImageType type;
+
+  if (check_mipmaps (image_id, DDS_SAVE_ARRAY))
+    return 1;
+
+  layers = gimp_image_get_layers (image_id, &num_layers);
+
+  if (num_layers > 1)
+    {
+      array = TRUE;
+
+      /* make sure all layers are the same size */
+      w = gimp_drawable_width (layers[0]);
+      h = gimp_drawable_height (layers[0]);
+
+      for (i = 1; i < num_layers && array; ++i)
+        {
+          if ((gimp_drawable_width (layers[i])  != w) ||
+              (gimp_drawable_height (layers[i]) != h))
+            array = FALSE;
+        }
+
+      if (array)
+        {
+          /* make sure all layers are the same type */
+          type = gimp_drawable_type (layers[0]);
+          for (i = 1; i < num_layers; ++i)
+            {
+              if (gimp_drawable_type (layers[i]) != type)
+                {
+                  array = FALSE;
+                  break;
+                }
+            }
+        }
+    }
+
+  return array;
+}
+
+static int
+get_array_size (gint32 image_id)
+{
+  gint *layers;
+  gint  num_layers;
+  gint i, w, h;
+  gint elements = 0;
+
+  layers = gimp_image_get_layers (image_id, &num_layers);
+
+  w = gimp_image_width (image_id);
+  h = gimp_image_height (image_id);
+
+  for (i = 0; i < num_layers; ++i)
+    {
+      if ((gimp_drawable_width  (layers[i]) == w) &&
+          (gimp_drawable_height (layers[i]) == h))
+        {
+          elements++;
+        }
+    }
+
+  return elements;
+}
+
+GimpPDBStatusType
+write_dds (gchar    *filename,
+           gint32    image_id,
+           gint32    drawable_id,
+           gboolean  interactive_dds,
+           gboolean  is_duplicate_image)
+{
+  FILE  *fp;
+  gchar *tmp;
+  int    rc = 0;
+
+  is_mipmap_chain_valid = check_mipmaps (image_id, dds_write_vals.savetype);
+
+  is_cubemap = check_cubemap (image_id);
+  is_volume  = check_volume (image_id);
+  is_array   = check_array (image_id);
+
+  if (interactive_dds)
+    {
+      if (! is_mipmap_chain_valid &&
+          dds_write_vals.mipmaps == DDS_MIPMAP_EXISTING)
+        dds_write_vals.mipmaps = DDS_MIPMAP_NONE;
+
+      if (! save_dialog (image_id, drawable_id))
+        return GIMP_PDB_CANCEL;
+    }
+  else
+    {
+      if (dds_write_vals.savetype == DDS_SAVE_CUBEMAP && ! is_cubemap)
+        {
+          g_message ("DDS: Cannot save image as cube map");
+          return GIMP_PDB_EXECUTION_ERROR;
+        }
+
+      if (dds_write_vals.savetype == DDS_SAVE_VOLUMEMAP && ! is_volume)
+        {
+          g_message ("DDS: Cannot save image as volume map");
+          return GIMP_PDB_EXECUTION_ERROR;
+        }
+
+      if (dds_write_vals.savetype == DDS_SAVE_VOLUMEMAP &&
+          dds_write_vals.compression != DDS_COMPRESS_NONE)
+        {
+          g_message ("DDS: Cannot save volume map with compression");
+          return GIMP_PDB_EXECUTION_ERROR;
+        }
+
+      if (dds_write_vals.mipmaps == DDS_MIPMAP_EXISTING &&
+          ! is_mipmap_chain_valid)
+        {
+          g_message ("DDS: Cannot save with existing mipmaps as the mipmap chain is incomplete");
+          return GIMP_PDB_EXECUTION_ERROR;
+        }
+    }
+
+  fp = g_fopen (filename, "wb");
+  if (fp == 0)
+    {
+      g_message ("Error opening %s", filename);
+      return GIMP_PDB_EXECUTION_ERROR;
+    }
+
+  if (strrchr (filename, '/'))
+    tmp = g_strdup_printf ("Saving %s:", strrchr (filename, '/') + 1);
+  else
+    tmp = g_strdup_printf ("Saving %s:", filename);
+  gimp_progress_init (tmp);
+  g_free (tmp);
+
+  /* If destructive changes are going to happen to the image,
+   * make sure we send a duplicate of it to write_image
+   */
+  if (! is_duplicate_image)
+    {
+      gint32 duplicate_image = gimp_image_duplicate (image_id);
+      rc = write_image (fp, duplicate_image, drawable_id);
+      gimp_image_delete (duplicate_image);
+    }
+  else
+    {
+      rc = write_image (fp, image_id, drawable_id);
+    }
+
+
+  fclose (fp);
+
+  return rc ? GIMP_PDB_SUCCESS : GIMP_PDB_EXECUTION_ERROR;
+}
+
+static void
+swap_rb (unsigned char *pixels,
+         unsigned int   n,
+         int            bpp)
+{
+  unsigned int i;
+  unsigned char t;
+
+  for (i = 0; i < n; ++i)
+    {
+      t = pixels[bpp * i + 0];
+      pixels[bpp * i + 0] = pixels[bpp * i + 2];
+      pixels[bpp * i + 2] = t;
+    }
+}
+
+static void
+alpha_exp (unsigned char *dst,
+           int            r,
+           int            g,
+           int            b,
+           int            a)
+{
+  float ar, ag, ab, aa;
+
+  ar = (float)r / 255.0f;
+  ag = (float)g / 255.0f;
+  ab = (float)b / 255.0f;
+
+  aa = MAX (ar, MAX (ag, ab));
+
+  if (aa < 1e-04f)
+    {
+      dst[0] = b;
+      dst[1] = g;
+      dst[2] = r;
+      dst[3] = 255;
+      return;
+    }
+
+  ar /= aa;
+  ag /= aa;
+  ab /= aa;
+
+  r = (int)floorf (255.0f * ar + 0.5f);
+  g = (int)floorf (255.0f * ag + 0.5f);
+  b = (int)floorf (255.0f * ab + 0.5f);
+  a = (int)floorf (255.0f * aa + 0.5f);
+
+  dst[0] = MAX (0, MIN (255, b));
+  dst[1] = MAX (0, MIN (255, g));
+  dst[2] = MAX (0, MIN (255, r));
+  dst[3] = MAX (0, MIN (255, a));
+}
+
+static void
+convert_pixels (unsigned char *dst,
+                unsigned char *src,
+                int            format,
+                int            w,
+                int            h,
+                int            d,
+                int            bpp,
+                unsigned char *palette,
+                int            mipmaps)
+{
+  unsigned int i, num_pixels;
+  unsigned char r, g, b, a;
+
+  if (d > 0)
+    num_pixels = get_volume_mipmapped_size (w, h, d, 1, 0, mipmaps, DDS_COMPRESS_NONE);
+  else
+    num_pixels = get_mipmapped_size (w, h, 1, 0, mipmaps, DDS_COMPRESS_NONE);
+
+  for (i = 0; i < num_pixels; ++i)
+    {
+      if (bpp == 1)
+        {
+          if (palette)
+            {
+              r = palette[3 * src[i] + 0];
+              g = palette[3 * src[i] + 1];
+              b = palette[3 * src[i] + 2];
+            }
+          else
+            r = g = b = src[i];
+
+          if (format == DDS_FORMAT_A8)
+            a = src[i];
+          else
+            a = 255;
+        }
+      else if (bpp == 2)
+        {
+          r = g = b = src[2 * i];
+          a = src[2 * i + 1];
+        }
+      else if (bpp == 3)
+        {
+          b = src[3 * i + 0];
+          g = src[3 * i + 1];
+          r = src[3 * i + 2];
+          a = 255;
+        }
+      else
+        {
+          b = src[4 * i + 0];
+          g = src[4 * i + 1];
+          r = src[4 * i + 2];
+          a = src[4 * i + 3];
+        }
+
+      switch (format)
+        {
+        case DDS_FORMAT_RGB8:
+          dst[3 * i + 0] = b;
+          dst[3 * i + 1] = g;
+          dst[3 * i + 2] = r;
+          break;
+        case DDS_FORMAT_RGBA8:
+          dst[4 * i + 0] = b;
+          dst[4 * i + 1] = g;
+          dst[4 * i + 2] = r;
+          dst[4 * i + 3] = a;
+          break;
+        case DDS_FORMAT_BGR8:
+          dst[3 * i + 0] = r;
+          dst[3 * i + 1] = g;
+          dst[3 * i + 2] = b;
+          break;
+        case DDS_FORMAT_ABGR8:
+          dst[4 * i + 0] = r;
+          dst[4 * i + 1] = g;
+          dst[4 * i + 2] = b;
+          dst[4 * i + 3] = a;
+          break;
+        case DDS_FORMAT_R5G6B5:
+          PUTL16(&dst[2 * i], pack_r5g6b5(r, g, b));
+          break;
+        case DDS_FORMAT_RGBA4:
+          PUTL16(&dst[2 * i], pack_rgba4(r, g, b, a));
+          break;
+        case DDS_FORMAT_RGB5A1:
+          PUTL16(&dst[2 * i], pack_rgb5a1(r, g, b, a));
+          break;
+        case DDS_FORMAT_RGB10A2:
+          PUTL32(&dst[4 * i], pack_rgb10a2(r, g, b, a));
+          break;
+        case DDS_FORMAT_R3G3B2:
+          dst[i] = pack_r3g3b2(r, g, b);
+          break;
+        case DDS_FORMAT_A8:
+          dst[i] = a;
+          break;
+        case DDS_FORMAT_L8:
+          dst[i] = rgb_to_luminance (r, g, b);
+          break;
+        case DDS_FORMAT_L8A8:
+          dst[2 * i + 0] = rgb_to_luminance (r, g, b);
+          dst[2 * i + 1] = a;
+          break;
+        case DDS_FORMAT_YCOCG:
+          dst[4 * i] = a;
+          RGB_to_YCoCg (&dst[4 * i], r, g, b);
+          break;
+        case DDS_FORMAT_AEXP:
+          alpha_exp (&dst[4 * i], r, g, b, a);
+          break;
+        default:
+          break;
+        }
+    }
+}
+
+static void
+get_mipmap_chain (unsigned char *dst,
+                  int            w,
+                  int            h,
+                  int            bpp,
+                  gint32         image_id,
+                  gint           drawable_id)
+{
+  gint *layers, num_layers;
+  GeglBuffer *buffer;
+  const Babl *format = 0;
+  int i, idx = 0, offset, mipw, miph;
+
+  if (bpp == 1)
+    format = babl_format ("Y' u8");
+  else if (bpp == 2)
+    format = babl_format ("Y'A u8");
+  else if (bpp == 3)
+    format = babl_format ("R'G'B' u8");
+  else
+    format = babl_format ("R'G'B'A u8");
+
+  layers = gimp_image_get_layers (image_id, &num_layers);
+
+  for (i = 0; i < num_layers; ++i)
+    {
+      if (layers[i] == drawable_id)
+        {
+          idx = i;
+          break;
+        }
+    }
+
+  if (i == num_layers) return;
+
+  offset = 0;
+
+  while (get_next_mipmap_dimensions (&mipw, &miph, w, h))
+    {
+      buffer = gimp_drawable_get_buffer (layers[++idx]);
+
+      if ((gegl_buffer_get_width (buffer)  != mipw) ||
+          (gegl_buffer_get_height (buffer) != miph))
+        {
+          g_object_unref (buffer);
+          return;
+        }
+
+      gegl_buffer_get (buffer, GEGL_RECTANGLE (0, 0, mipw, miph), 1.0, format,
+                       dst + offset, GEGL_AUTO_ROWSTRIDE, GEGL_ABYSS_NONE);
+      g_object_unref (buffer);
+
+      /* we need BGRX or BGRA */
+      if (bpp >= 3)
+        swap_rb (dst + offset, mipw * miph, bpp);
+
+      offset += (mipw * miph * bpp);
+      w = mipw;
+      h = miph;
+    }
+}
+
+static void
+write_layer (FILE   *fp,
+             gint32  image_id,
+             gint32  drawable_id,
+             int     w,
+             int     h,
+             int     bpp,
+             int     fmtbpp,
+             int     mipmaps)
+{
+  GeglBuffer *buffer;
+  const Babl *format = 0;
+  GimpImageBaseType basetype;
+  GimpImageType type;
+  unsigned char *src, *dst, *fmtdst, *tmp;
+  unsigned char *palette = NULL;
+  int i, c, x, y, size, fmtsize, offset, colors;
+  int compression = dds_write_vals.compression;
+  int flags = 0;
+
+  basetype = gimp_image_base_type (image_id);
+  type = gimp_drawable_type (drawable_id);
+
+  buffer = gimp_drawable_get_buffer (drawable_id);
+
+  src = g_malloc (w * h * bpp);
+
+  if (basetype == GIMP_INDEXED)
+    format = gimp_drawable_get_format (drawable_id);
+  else if (bpp == 1)
+    format = babl_format ("Y' u8");
+  else if (bpp == 2)
+    format = babl_format ("Y'A u8");
+  else if (bpp == 3)
+    format = babl_format ("R'G'B' u8");
+  else
+    format = babl_format ("R'G'B'A u8");
+
+  gegl_buffer_get (buffer, GEGL_RECTANGLE (0, 0, w, h), 1.0, format, src,
+                   GEGL_AUTO_ROWSTRIDE, GEGL_ABYSS_NONE);
+
+  if (basetype == GIMP_INDEXED)
+    {
+      palette = gimp_image_get_colormap (image_id, &colors);
+
+      if (type == GIMP_INDEXEDA_IMAGE)
+        {
+          tmp = g_malloc (w * h);
+          for (i = 0; i < w * h; ++i)
+            tmp[i] = src[2 * i];
+          g_free (src);
+          src = tmp;
+          bpp = 1;
+        }
+    }
+
+  /* we want and assume BGRA ordered pixels for bpp >= 3 from here and
+     onwards */
+  if (bpp >= 3)
+    swap_rb (src, w * h, bpp);
+
+  if (compression == DDS_COMPRESS_BC3N)
+    {
+      if (bpp != 4)
+        {
+          fmtsize = w * h * 4;
+          fmtdst = g_malloc (fmtsize);
+          convert_pixels (fmtdst, src, DDS_FORMAT_RGBA8, w, h, 0, bpp,
+                          palette, 1);
+          g_free (src);
+          src = fmtdst;
+          bpp = 4;
+        }
+
+      for (y = 0; y < h; ++y)
+        {
+          for (x = 0; x < w; ++x)
+            {
+              /* set alpha to red (x) */
+              src[y * (w * 4) + (x * 4) + 3] =
+                src[y * (w * 4) + (x * 4) + 2];
+              /* set red to 1 */
+              src[y * (w * 4) + (x * 4) + 2] = 255;
+            }
+        }
+    }
+
+  /* RXGB (Doom3) */
+  if (compression == DDS_COMPRESS_RXGB)
+    {
+      if (bpp != 4)
+        {
+          fmtsize = w * h * 4;
+          fmtdst = g_malloc (fmtsize);
+          convert_pixels (fmtdst, src, DDS_FORMAT_RGBA8, w, h, 0, bpp,
+                          palette, 1);
+          g_free (src);
+          src = fmtdst;
+          bpp = 4;
+        }
+
+      for (y = 0; y < h; ++y)
+        {
+          for (x = 0; x < w; ++x)
+            {
+              /* swap red and alpha */
+              c = src[y * (w * 4) + (x * 4) + 3];
+              src[y * (w * 4) + (x * 4) + 3] =
+                src[y * (w * 4) + (x * 4) + 2];
+              src[y * (w * 4) + (x * 4) + 2] = c;
+            }
+        }
+    }
+
+  if (compression == DDS_COMPRESS_YCOCG ||
+      compression == DDS_COMPRESS_YCOCGS) /* convert to YCoCG */
+    {
+      fmtsize = w * h * 4;
+      fmtdst = g_malloc (fmtsize);
+      convert_pixels (fmtdst, src, DDS_FORMAT_YCOCG, w, h, 0, bpp,
+                      palette, 1);
+      g_free (src);
+      src = fmtdst;
+      bpp = 4;
+    }
+
+  if (compression == DDS_COMPRESS_AEXP)
+    {
+      fmtsize = w * h * 4;
+      fmtdst = g_malloc (fmtsize);
+      convert_pixels (fmtdst, src, DDS_FORMAT_AEXP, w, h, 0, bpp,
+                      palette, 1);
+      g_free (src);
+      src = fmtdst;
+      bpp = 4;
+    }
+
+  if (compression == DDS_COMPRESS_NONE)
+    {
+      if (mipmaps > 1)
+        {
+          /* pre-convert indexed images to RGB for better quality mipmaps
+             if a pixel format conversion is requested */
+          if (dds_write_vals.format > DDS_FORMAT_DEFAULT && basetype == GIMP_INDEXED)
+            {
+              fmtsize = get_mipmapped_size (w, h, 3, 0, mipmaps, DDS_COMPRESS_NONE);
+              fmtdst = g_malloc (fmtsize);
+              convert_pixels (fmtdst, src, DDS_FORMAT_RGB8, w, h, 0, bpp,
+                              palette, 1);
+              g_free (src);
+              src = fmtdst;
+              bpp = 3;
+              palette = NULL;
+            }
+
+          size = get_mipmapped_size (w, h, bpp, 0, mipmaps, DDS_COMPRESS_NONE);
+          dst = g_malloc (size);
+          if (dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE)
+            {
+              generate_mipmaps (dst, src, w, h, bpp, palette != NULL,
+                                mipmaps,
+                                dds_write_vals.mipmap_filter,
+                                dds_write_vals.mipmap_wrap,
+                                dds_write_vals.gamma_correct + dds_write_vals.srgb,
+                                dds_write_vals.gamma,
+                                dds_write_vals.preserve_alpha_coverage,
+                                dds_write_vals.alpha_test_threshold);
+            }
+          else
+            {
+              memcpy (dst, src, w * h * bpp);
+              get_mipmap_chain (dst + (w * h * bpp), w, h, bpp, image_id, drawable_id);
+            }
+
+          if (dds_write_vals.format > DDS_FORMAT_DEFAULT)
+            {
+              fmtsize = get_mipmapped_size (w, h, fmtbpp, 0, mipmaps,
+                                            DDS_COMPRESS_NONE);
+              fmtdst = g_malloc (fmtsize);
+
+              convert_pixels (fmtdst, dst, dds_write_vals.format, w, h, 0, bpp,
+                              palette, mipmaps);
+
+              g_free (dst);
+              dst = fmtdst;
+              bpp = fmtbpp;
+            }
+
+          offset = 0;
+
+          for (i = 0; i < mipmaps; ++i)
+            {
+              size = get_mipmapped_size (w, h, bpp, i, 1, DDS_COMPRESS_NONE);
+              fwrite (dst + offset, 1, size, fp);
+              offset += size;
+            }
+
+          g_free (dst);
+        }
+      else
+        {
+          if (dds_write_vals.format > DDS_FORMAT_DEFAULT)
+            {
+              fmtdst = g_malloc (h * w * fmtbpp);
+              convert_pixels (fmtdst, src, dds_write_vals.format, w, h, 0, bpp,
+                              palette, 1);
+              g_free (src);
+              src = fmtdst;
+              bpp = fmtbpp;
+            }
+
+          fwrite (src, 1, h * w * bpp, fp);
+        }
+    }
+  else
+    {
+      size = get_mipmapped_size (w, h, bpp, 0, mipmaps, compression);
+
+      dst = g_malloc (size);
+
+      if (basetype == GIMP_INDEXED)
+        {
+          fmtsize = get_mipmapped_size (w, h, 3, 0, mipmaps,
+                                        DDS_COMPRESS_NONE);
+          fmtdst = g_malloc (fmtsize);
+          convert_pixels (fmtdst, src, DDS_FORMAT_RGB8, w, h, 0, bpp,
+                          palette, mipmaps);
+          g_free (src);
+          src = fmtdst;
+          bpp = 3;
+        }
+
+      if (mipmaps > 1)
+        {
+          fmtsize = get_mipmapped_size (w, h, bpp, 0, mipmaps,
+                                        DDS_COMPRESS_NONE);
+          fmtdst = g_malloc (fmtsize);
+          if (dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE)
+            {
+              generate_mipmaps (fmtdst, src, w, h, bpp, 0, mipmaps,
+                                dds_write_vals.mipmap_filter,
+                                dds_write_vals.mipmap_wrap,
+                                dds_write_vals.gamma_correct + dds_write_vals.srgb,
+                                dds_write_vals.gamma,
+                                dds_write_vals.preserve_alpha_coverage,
+                                dds_write_vals.alpha_test_threshold);
+            }
+          else
+            {
+              memcpy (fmtdst, src, w * h * bpp);
+              get_mipmap_chain (fmtdst + (w * h * bpp), w, h, bpp, image_id, drawable_id);
+            }
+
+          g_free (src);
+          src = fmtdst;
+        }
+
+      flags = 0;
+      if (dds_write_vals.perceptual_metric) flags |= DXT_PERCEPTUAL;
+
+      dxt_compress (dst, src, compression, w, h, bpp, mipmaps, flags);
+
+      fwrite (dst, 1, size, fp);
+
+      g_free (dst);
+    }
+
+  g_free (src);
+
+  g_object_unref (buffer);
+}
+
+static void
+write_volume_mipmaps (FILE   *fp,
+                      gint32  image_id,
+                      gint32 *layers,
+                      int     w,
+                      int     h,
+                      int     d,
+                      int     bpp,
+                      int     fmtbpp,
+                      int     mipmaps)
+{
+  int i, size, offset, colors;
+  unsigned char *src, *dst, *tmp, *fmtdst;
+  unsigned char *palette = 0;
+  GeglBuffer *buffer;
+  const Babl *format;
+  GimpImageBaseType type;
+
+  type = gimp_image_base_type (image_id);
+
+  if (dds_write_vals.compression != DDS_COMPRESS_NONE) return;
+
+  src = g_malloc (w * h * bpp * d);
+
+  if (bpp == 1)
+    format = babl_format ("Y' u8");
+  else if (bpp == 2)
+    format = babl_format ("Y'A u8");
+  else if (bpp == 3)
+    format = babl_format ("R'G'B' u8");
+  else
+    format = babl_format ("R'G'B'A u8");
+
+  if (gimp_image_base_type (image_id) == GIMP_INDEXED)
+    palette = gimp_image_get_colormap (image_id, &colors);
+
+  offset = 0;
+  for (i = 0; i < d; ++i)
+    {
+      buffer = gimp_drawable_get_buffer (layers[i]);
+      gegl_buffer_get (buffer, GEGL_RECTANGLE (0, 0, w, h), 1.0, format,
+                       src + offset, GEGL_AUTO_ROWSTRIDE, GEGL_ABYSS_NONE);
+      offset += (w * h * bpp);
+      g_object_unref (buffer);
+    }
+
+  if (gimp_drawable_type (layers[0]) == GIMP_INDEXEDA_IMAGE)
+    {
+      tmp = g_malloc (w * h * d);
+      for (i = 0; i < w * h * d; ++i)
+        tmp[i] = src[2 * i];
+      g_free (src);
+      src = tmp;
+      bpp = 1;
+    }
+
+  /* we want and assume BGRA ordered pixels for bpp >= 3 from here and
+     onwards */
+  if (bpp >= 3)
+    swap_rb (src, w * h * d, bpp);
+
+  /* pre-convert indexed images to RGB for better mipmaps if a
+     pixel format conversion is requested */
+  if (dds_write_vals.format > DDS_FORMAT_DEFAULT && type == GIMP_INDEXED)
+    {
+      size = get_volume_mipmapped_size (w, h, d, 3, 0, mipmaps,
+                                        DDS_COMPRESS_NONE);
+      dst = g_malloc (size);
+      convert_pixels (dst, src, DDS_FORMAT_RGB8, w, h, d, bpp, palette, 1);
+      g_free (src);
+      src = dst;
+      bpp = 3;
+      palette = NULL;
+    }
+
+  size = get_volume_mipmapped_size (w, h, d, bpp, 0, mipmaps,
+                                    dds_write_vals.compression);
+
+  dst = g_malloc (size);
+
+  offset = get_volume_mipmapped_size (w, h, d, bpp, 0, 1,
+                                      dds_write_vals.compression);
+
+  generate_volume_mipmaps (dst, src, w, h, d, bpp,
+                           palette != NULL, mipmaps,
+                           dds_write_vals.mipmap_filter,
+                           dds_write_vals.mipmap_wrap,
+                           dds_write_vals.gamma_correct + dds_write_vals.srgb,
+                           dds_write_vals.gamma);
+
+  if (dds_write_vals.format > DDS_FORMAT_DEFAULT)
+    {
+      size = get_volume_mipmapped_size (w, h, d, fmtbpp, 0, mipmaps,
+                                        dds_write_vals.compression);
+      offset = get_volume_mipmapped_size (w, h, d, fmtbpp, 0, 1,
+                                          dds_write_vals.compression);
+      fmtdst = g_malloc (size);
+
+      convert_pixels (fmtdst, dst, dds_write_vals.format, w, h, d, bpp,
+                      palette, mipmaps);
+      g_free (dst);
+      dst = fmtdst;
+    }
+
+  fwrite (dst + offset, 1, size, fp);
+
+  g_free (src);
+  g_free (dst);
+}
+
+static gboolean
+write_image (FILE   *fp,
+             gint32  image_id,
+             gint32  drawable_id)
+{
+  GimpImageType drawable_type;
+  GimpImageBaseType basetype;
+  gint i, w, h;
+  gint bpp = 0;
+  gint fmtbpp = 0;
+  gint has_alpha = 0;
+  gint num_mipmaps;
+  guchar hdr[DDS_HEADERSIZE];
+  guchar hdr10[DDS_HEADERSIZE_DX10];
+  guint flags = 0, pflags = 0, caps = 0, caps2 = 0, size = 0;
+  guint rmask = 0, gmask = 0, bmask = 0, amask = 0;
+  guint fourcc = 0;
+  DXGI_FORMAT dxgi_format = DXGI_FORMAT_UNKNOWN;
+  gint32  num_layers;
+  gint32 *layers;
+  guchar *cmap;
+  gint    colors;
+  guchar zero[4] = {0, 0, 0, 0};
+  gint is_dx10 = 0;
+  gint array_size = 1;
+
+  if (dds_write_vals.flip_image)
+    {
+      gimp_image_flip (image_id, GIMP_ORIENTATION_VERTICAL);
+      drawable_id = gimp_image_get_active_drawable (image_id);
+    }
+
+  layers = gimp_image_get_layers (image_id, &num_layers);
+
+  if (dds_write_vals.mipmaps == DDS_MIPMAP_EXISTING)
+    drawable_id = layers[0];
+
+  if (dds_write_vals.savetype == DDS_SAVE_SELECTED_LAYER)
+    {
+      w = gimp_drawable_width (drawable_id);
+      h = gimp_drawable_height (drawable_id);
+    }
+  else
+    {
+      w = gimp_image_width (image_id);
+      h = gimp_image_height (image_id);
+    }
+
+  basetype = gimp_image_base_type (image_id);
+  drawable_type = gimp_drawable_type (drawable_id);
+
+  switch (drawable_type)
+    {
+    case GIMP_RGB_IMAGE:      bpp = 3; break;
+    case GIMP_RGBA_IMAGE:     bpp = 4; break;
+    case GIMP_GRAY_IMAGE:     bpp = 1; break;
+    case GIMP_GRAYA_IMAGE:    bpp = 2; break;
+    case GIMP_INDEXED_IMAGE:  bpp = 1; break;
+    case GIMP_INDEXEDA_IMAGE: bpp = 2; break;
+    default:
+                              break;
+    }
+
+  if (dds_write_vals.format > DDS_FORMAT_DEFAULT)
+    {
+      for (i = 0; ; ++i)
+        {
+          if (format_info[i].format == dds_write_vals.format)
+            {
+              fmtbpp = format_info[i].bpp;
+              has_alpha = format_info[i].alpha;
+              rmask = format_info[i].rmask;
+              gmask = format_info[i].gmask;
+              bmask = format_info[i].bmask;
+              amask = format_info[i].amask;
+              dxgi_format = format_info[i].dxgi_format;
+              break;
+            }
+        }
+    }
+  else if (bpp == 1)
+    {
+      if (basetype == GIMP_INDEXED)
+        {
+          fmtbpp = 1;
+          has_alpha = 0;
+          rmask = bmask = gmask = amask = 0;
+        }
+      else
+        {
+          fmtbpp = 1;
+          has_alpha = 0;
+          rmask = 0x000000ff;
+          gmask = bmask = amask = 0;
+          dxgi_format = DXGI_FORMAT_R8_UNORM;
+        }
+    }
+  else if (bpp == 2)
+    {
+      if (basetype == GIMP_INDEXED)
+        {
+          fmtbpp = 1;
+          has_alpha = 0;
+          rmask = gmask = bmask = amask = 0;
+        }
+      else
+        {
+          fmtbpp = 2;
+          has_alpha = 1;
+          rmask = 0x000000ff;
+          gmask = 0x000000ff;
+          bmask = 0x000000ff;
+          amask = 0x0000ff00;
+        }
+    }
+  else if (bpp == 3)
+    {
+      fmtbpp = 3;
+      rmask = 0x00ff0000;
+      gmask = 0x0000ff00;
+      bmask = 0x000000ff;
+      amask = 0x00000000;
+    }
+  else
+    {
+      fmtbpp = 4;
+      has_alpha = 1;
+      rmask = 0x00ff0000;
+      gmask = 0x0000ff00;
+      bmask = 0x000000ff;
+      amask = 0xff000000;
+      dxgi_format = DXGI_FORMAT_B8G8R8A8_UNORM;
+    }
+
+  memset (hdr, 0, DDS_HEADERSIZE);
+
+  PUTL32(hdr,       FOURCC ('D','D','S',' '));
+  PUTL32(hdr + 4,   124);
+  PUTL32(hdr + 12,  h);
+  PUTL32(hdr + 16,  w);
+  PUTL32(hdr + 76,  32);
+
+  if (dds_write_vals.compression == DDS_COMPRESS_NONE)
+    {
+      PUTL32(hdr + 88,  fmtbpp << 3);
+      PUTL32(hdr + 92,  rmask);
+      PUTL32(hdr + 96,  gmask);
+      PUTL32(hdr + 100, bmask);
+      PUTL32(hdr + 104, amask);
+    }
+
+  /*
+     put some information in the reserved area to identify the origin
+     of the image
+     */
+  PUTL32(hdr + 32, FOURCC ('G','I','M','P'));
+  PUTL32(hdr + 36, FOURCC ('-','D','D','S'));
+  PUTL32(hdr + 40, DDS_PLUGIN_VERSION);
+
+  flags = DDSD_CAPS | DDSD_PIXELFORMAT | DDSD_WIDTH | DDSD_HEIGHT;
+
+  caps = DDSCAPS_TEXTURE;
+  if (dds_write_vals.mipmaps)
+    {
+      flags |= DDSD_MIPMAPCOUNT;
+      caps |= (DDSCAPS_COMPLEX | DDSCAPS_MIPMAP);
+      num_mipmaps = get_num_mipmaps (w, h);
+    }
+  else
+    {
+      num_mipmaps = 1;
+    }
+
+  if ((dds_write_vals.savetype == DDS_SAVE_CUBEMAP) && is_cubemap)
+    {
+      caps |= DDSCAPS_COMPLEX;
+      caps2 |= (DDSCAPS2_CUBEMAP | DDSCAPS2_CUBEMAP_ALL_FACES);
+    }
+  else if ((dds_write_vals.savetype == DDS_SAVE_VOLUMEMAP) && is_volume)
+    {
+      PUTL32(hdr + 24, num_layers); /* depth */
+      flags |= DDSD_DEPTH;
+      caps |= DDSCAPS_COMPLEX;
+      caps2 |= DDSCAPS2_VOLUME;
+    }
+
+  PUTL32(hdr + 28,  num_mipmaps);
+  PUTL32(hdr + 108, caps);
+  PUTL32(hdr + 112, caps2);
+
+  if (dds_write_vals.compression == DDS_COMPRESS_NONE)
+    {
+      flags |= DDSD_PITCH;
+
+      if (dds_write_vals.format > DDS_FORMAT_DEFAULT)
+        {
+          if (dds_write_vals.format == DDS_FORMAT_A8)
+            pflags |= DDPF_ALPHA;
+          else
+            {
+              if (((fmtbpp == 1) || (dds_write_vals.format == DDS_FORMAT_L8A8)) &&
+                  (dds_write_vals.format != DDS_FORMAT_R3G3B2))
+                pflags |= DDPF_LUMINANCE;
+              else
+                pflags |= DDPF_RGB;
+            }
+        }
+      else
+        {
+          if (bpp == 1)
+            {
+              if (basetype == GIMP_INDEXED)
+                pflags |= DDPF_PALETTEINDEXED8;
+              else
+                pflags |= DDPF_LUMINANCE;
+            }
+          else if ((bpp == 2) && (basetype == GIMP_INDEXED))
+            {
+              pflags |= DDPF_PALETTEINDEXED8;
+            }
+          else
+            {
+              pflags |= DDPF_RGB;
+            }
+        }
+
+      if (has_alpha)
+        pflags |= DDPF_ALPHAPIXELS;
+
+      PUTL32 (hdr + 8,  flags);
+      PUTL32 (hdr + 20, w * fmtbpp); /* pitch */
+      PUTL32 (hdr + 80, pflags);
+
+      /*
+       * write extra fourcc info - this is special to GIMP DDS. When the image
+       * is read by the plugin, we can detect the added information to decode
+       * the pixels
+       */
+      if (dds_write_vals.format == DDS_FORMAT_AEXP)
+        {
+          PUTL32 (hdr + 44, FOURCC ('A','E','X','P'));
+        }
+      else if (dds_write_vals.format == DDS_FORMAT_YCOCG)
+        {
+          PUTL32 (hdr + 44, FOURCC ('Y','C','G','1'));
+        }
+    }
+  else
+    {
+      flags |= DDSD_LINEARSIZE;
+      pflags = DDPF_FOURCC;
+
+      switch (dds_write_vals.compression)
+        {
+        case DDS_COMPRESS_BC1:
+          fourcc = FOURCC ('D','X','T','1');
+          dxgi_format = DXGI_FORMAT_BC1_UNORM;
+          break;
+
+        case DDS_COMPRESS_BC2:
+          fourcc = FOURCC ('D','X','T','3');
+          dxgi_format = DXGI_FORMAT_BC2_UNORM;
+          break;
+
+        case DDS_COMPRESS_BC3:
+        case DDS_COMPRESS_BC3N:
+        case DDS_COMPRESS_YCOCG:
+        case DDS_COMPRESS_YCOCGS:
+        case DDS_COMPRESS_AEXP:
+          fourcc = FOURCC ('D','X','T','5');
+          dxgi_format = DXGI_FORMAT_BC3_UNORM;
+          break;
+
+        case DDS_COMPRESS_RXGB:
+          fourcc = FOURCC ('R','X','G','B');
+          dxgi_format = DXGI_FORMAT_BC3_UNORM;
+          break;
+
+        case DDS_COMPRESS_BC4:
+          fourcc = FOURCC ('A','T','I','1');
+          dxgi_format = DXGI_FORMAT_BC4_UNORM;
+          //is_dx10 = 1;
+          break;
+
+        case DDS_COMPRESS_BC5:
+          fourcc = FOURCC ('A','T','I','2');
+          dxgi_format = DXGI_FORMAT_BC5_UNORM;
+          //is_dx10 = 1;
+          break;
+        }
+
+      if ((dds_write_vals.compression == DDS_COMPRESS_BC3N) ||
+          (dds_write_vals.compression == DDS_COMPRESS_RXGB))
+        {
+          pflags |= DDPF_NORMAL;
+        }
+
+      PUTL32 (hdr + 8,  flags);
+      PUTL32 (hdr + 80, pflags);
+      PUTL32 (hdr + 84, fourcc);
+
+      size = ((w + 3) >> 2) * ((h + 3) >> 2);
+      if ((dds_write_vals.compression == DDS_COMPRESS_BC1) ||
+          (dds_write_vals.compression == DDS_COMPRESS_BC4))
+        size *= 8;
+      else
+        size *= 16;
+
+      PUTL32 (hdr + 20, size); /* linear size */
+
+      /*
+       * write extra fourcc info - this is special to GIMP DDS. When the image
+       * is read by the plugin, we can detect the added information to decode
+       * the pixels
+       */
+      if (dds_write_vals.compression == DDS_COMPRESS_AEXP)
+        {
+          PUTL32 (hdr + 44, FOURCC ('A','E','X','P'));
+        }
+      else if (dds_write_vals.compression == DDS_COMPRESS_YCOCG)
+        {
+          PUTL32 (hdr + 44, FOURCC ('Y','C','G','1'));
+        }
+      else if (dds_write_vals.compression == DDS_COMPRESS_YCOCGS)
+        {
+          PUTL32 (hdr + 44, FOURCC ('Y','C','G','2'));
+        }
+    }
+
+  /* texture arrays require a DX10 header */
+  if (dds_write_vals.savetype == DDS_SAVE_ARRAY)
+    is_dx10 = 1;
+
+  if (is_dx10)
+    {
+      array_size = (dds_write_vals.savetype == DDS_SAVE_SELECTED_LAYER ||
+                    dds_write_vals.savetype == DDS_SAVE_VISIBLE_LAYERS) ? 1 : get_array_size (image_id);
+
+      PUTL32 (hdr10 +  0, dxgi_format);
+      PUTL32 (hdr10 +  4, D3D10_RESOURCE_DIMENSION_TEXTURE2D);
+      PUTL32 (hdr10 +  8, 0);
+      PUTL32 (hdr10 + 12, array_size);
+      PUTL32 (hdr10 + 16, 0);
+
+      /* update main header accordingly */
+      PUTL32 (hdr + 80, pflags | DDPF_FOURCC);
+      PUTL32 (hdr + 84, FOURCC ('D','X','1','0'));
+    }
+
+  fwrite (hdr, DDS_HEADERSIZE, 1, fp);
+
+  if (is_dx10)
+    fwrite (hdr10, DDS_HEADERSIZE_DX10, 1, fp);
+
+  /* write palette for indexed images */
+  if ((basetype == GIMP_INDEXED) &&
+      (dds_write_vals.format == DDS_FORMAT_DEFAULT) &&
+      (dds_write_vals.compression == DDS_COMPRESS_NONE))
+    {
+      cmap = gimp_image_get_colormap (image_id, &colors);
+
+      for (i = 0; i < colors; ++i)
+        {
+          fwrite (&cmap[3 * i], 1, 3, fp);
+          if (i == dds_write_vals.transindex)
+            fputc (0, fp);
+          else
+            fputc (255, fp);
+        }
+
+      for (; i < 256; ++i)
+        fwrite (zero, 1, 4, fp);
+    }
+
+  if (dds_write_vals.savetype == DDS_SAVE_CUBEMAP)
+    {
+      for (i = 0; i < 6; ++i)
+        {
+          write_layer (fp, image_id, cubemap_faces[i], w, h, bpp, fmtbpp,
+                       num_mipmaps);
+          gimp_progress_update ((float)(i + 1) / 6.0);
+        }
+    }
+  else if (dds_write_vals.savetype == DDS_SAVE_VOLUMEMAP)
+    {
+      for (i = 0; i < num_layers; ++i)
+        {
+          write_layer (fp, image_id, layers[i], w, h, bpp, fmtbpp, 1);
+          gimp_progress_update ((float)i / (float)num_layers);
+        }
+
+      if (num_mipmaps > 1)
+        write_volume_mipmaps (fp, image_id, layers, w, h, num_layers,
+                              bpp, fmtbpp, num_mipmaps);
+    }
+  else if (dds_write_vals.savetype == DDS_SAVE_ARRAY)
+    {
+      for (i = 0; i < num_layers; ++i)
+        {
+          if ((gimp_drawable_width  (layers[i]) == w) &&
+              (gimp_drawable_height (layers[i]) == h))
+            {
+              write_layer (fp, image_id, layers[i],
+                           w, h, bpp, fmtbpp, num_mipmaps);
+            }
+
+          gimp_progress_update ((float)i / (float)num_layers);
+        }
+    }
+  else
+    {
+      if (dds_write_vals.savetype == DDS_SAVE_VISIBLE_LAYERS)
+        drawable_id = gimp_image_merge_visible_layers (image_id, 1);
+      write_layer (fp, image_id, drawable_id, w, h, bpp, fmtbpp, num_mipmaps);
+    }
+
+  gimp_progress_update (1.0);
+
+  return TRUE;
+}
+
+static GtkWidget *
+string_value_combo_new (string_value_t *strings,
+                        int             active_value)
+{
+  GtkWidget *opt;
+  GtkCellRenderer *renderer;
+  GtkListStore *store;
+  GtkTreeIter iter;
+  gint i;
+  gint active = 0;
+
+  store = gtk_list_store_new (3, G_TYPE_INT, G_TYPE_STRING, G_TYPE_BOOLEAN);
+  for (i = 0; strings[i].string; ++i)
+    {
+      if (strings[i].value == active_value) active = i;
+      gtk_list_store_append (store, &iter);
+      gtk_list_store_set (store, &iter,
+                          0, strings[i].value,
+                          1, strings[i].string,
+                          2, 1,
+                          -1);
+    }
+
+  renderer = gtk_cell_renderer_text_new ();
+
+  opt = gtk_combo_box_new_with_model (GTK_TREE_MODEL (store));
+  gtk_cell_layout_pack_start (GTK_CELL_LAYOUT (opt), renderer, 1);
+  gtk_cell_layout_set_attributes (GTK_CELL_LAYOUT (opt), renderer,
+                                  "text", COMBO_STRING,
+                                  "sensitive", COMBO_SENSITIVE,
+                                  NULL);
+
+  gtk_combo_box_set_active (GTK_COMBO_BOX (opt), active);
+
+  g_object_unref (store);
+
+  return opt;
+}
+
+static void
+string_value_combo_selected (GtkWidget *widget,
+                             gpointer   data)
+{
+  gint value;
+  GtkTreeIter iter;
+  GtkTreeModel *model;
+
+  model = gtk_combo_box_get_model (GTK_COMBO_BOX (widget));
+  gtk_combo_box_get_active_iter (GTK_COMBO_BOX (widget), &iter);
+  gtk_tree_model_get (model, &iter, COMBO_VALUE, &value, -1);
+
+  *((int *)data) = value;
+}
+
+static void
+string_value_combo_set_item_sensitive (GtkWidget *widget,
+                                       gint       value,
+                                       gboolean   sensitive)
+{
+  GtkTreeIter iter;
+  GtkTreeModel *model;
+  gint val;
+
+  model = gtk_combo_box_get_model (GTK_COMBO_BOX (widget));
+  gtk_tree_model_get_iter_first (model, &iter);
+  do
+    {
+      gtk_tree_model_get (model, &iter, COMBO_VALUE, &val, -1);
+      if (val == value)
+        {
+          gtk_list_store_set (GTK_LIST_STORE (model), &iter,
+                              COMBO_SENSITIVE, sensitive, -1);
+          break;
+        }
+    } while (gtk_tree_model_iter_next (model, &iter));
+}
+
+static void
+string_value_combo_set_active (GtkWidget *widget,
+                               gint       value)
+{
+  GtkTreeIter iter;
+  GtkTreeModel *model;
+  int val;
+
+  model = gtk_combo_box_get_model (GTK_COMBO_BOX (widget));
+  gtk_tree_model_get_iter_first (model, &iter);
+  do
+    {
+      gtk_tree_model_get (model, &iter, COMBO_VALUE, &val, -1);
+      if (val == value)
+        {
+          gtk_combo_box_set_active_iter (GTK_COMBO_BOX (widget), &iter);
+          break;
+        }
+    } while (gtk_tree_model_iter_next (model, &iter));
+}
+
+static void
+save_dialog_response (GtkWidget *widget,
+                      gint       response_id,
+                      gpointer   data)
+{
+  switch (response_id)
+    {
+    case GTK_RESPONSE_OK:
+      runme = TRUE;
+
+    default:
+      gtk_widget_destroy (widget);
+      break;
+    }
+}
+
+static void
+compression_selected (GtkWidget *widget,
+                      gpointer   data)
+{
+  GtkTreeIter iter;
+  GtkTreeModel *model;
+
+  model = gtk_combo_box_get_model (GTK_COMBO_BOX (widget));
+  gtk_combo_box_get_active_iter (GTK_COMBO_BOX (widget), &iter);
+  gtk_tree_model_get (model, &iter, COMBO_VALUE,
+                      &dds_write_vals.compression,
+                      -1);
+
+  gtk_widget_set_sensitive (format_opt,
+                            dds_write_vals.compression == DDS_COMPRESS_NONE);
+  gtk_widget_set_sensitive (pm_chk,
+                            dds_write_vals.compression != DDS_COMPRESS_NONE);
+}
+
+static void
+savetype_selected (GtkWidget *widget,
+                   gpointer   data)
+{
+  gint32 image_id = *((gint32 *)data);
+
+  dds_write_vals.savetype = gtk_combo_box_get_active (GTK_COMBO_BOX (widget));
+
+  switch (dds_write_vals.savetype)
+    {
+    case DDS_SAVE_SELECTED_LAYER:
+    case DDS_SAVE_VISIBLE_LAYERS:
+    case DDS_SAVE_CUBEMAP:
+    case DDS_SAVE_ARRAY:
+      gtk_widget_set_sensitive (compress_opt, TRUE);
+      break;
+
+    case DDS_SAVE_VOLUMEMAP:
+      dds_write_vals.compression = DDS_COMPRESS_NONE;
+      gtk_combo_box_set_active (GTK_COMBO_BOX (compress_opt),
+                                DDS_COMPRESS_NONE);
+      gtk_widget_set_sensitive (compress_opt, FALSE);
+      break;
+    }
+
+  string_value_combo_set_item_sensitive (mipmap_opt, DDS_MIPMAP_EXISTING,
+                                         check_mipmaps (image_id, dds_write_vals.savetype));
+}
+
+static void
+mipmaps_selected (GtkWidget *widget,
+                  gpointer   data)
+{
+  GtkTreeModel *model;
+  GtkTreeIter   iter;
+
+  model = gtk_combo_box_get_model (GTK_COMBO_BOX (widget));
+  gtk_combo_box_get_active_iter (GTK_COMBO_BOX (widget), &iter);
+  gtk_tree_model_get (model, &iter, COMBO_VALUE,
+                      &dds_write_vals.mipmaps, -1);
+
+  gtk_widget_set_sensitive (mipmap_filter_opt,
+                            dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE);
+  gtk_widget_set_sensitive (mipmap_wrap_opt,
+                            dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE);
+  gtk_widget_set_sensitive (gamma_chk,
+                            dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE);
+  gtk_widget_set_sensitive (srgb_chk,
+                            (dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE) &&
+                            dds_write_vals.gamma_correct);
+  gtk_widget_set_sensitive (gamma_spin,
+                            (dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE) &&
+                            dds_write_vals.gamma_correct &&
+                            !dds_write_vals.srgb);
+  gtk_widget_set_sensitive (alpha_coverage_chk,
+                            dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE);
+  gtk_widget_set_sensitive (alpha_test_threshold_spin,
+                            (dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE) &&
+                            dds_write_vals.preserve_alpha_coverage);
+}
+
+static void
+toggle_clicked (GtkWidget *widget,
+                gpointer   data)
+{
+  gint *flag = (int *)data;
+
+  (*flag) = !(*flag);
+}
+
+static void
+transindex_clicked (GtkWidget *widget,
+                    gpointer   data)
+{
+  GtkWidget *spin = GTK_WIDGET (g_object_get_data (G_OBJECT (widget), "spin"));
+
+  if (gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (widget)))
+    {
+      dds_write_vals.transindex = 0;
+      gtk_widget_set_sensitive (spin, TRUE);
+      gtk_spin_button_set_value (GTK_SPIN_BUTTON (spin), 0);
+    }
+  else
+    {
+      gtk_widget_set_sensitive (spin, FALSE);
+      dds_write_vals.transindex = -1;
+    }
+}
+
+static void
+transindex_changed (GtkWidget *widget,
+                    gpointer   data)
+{
+  dds_write_vals.transindex =
+    gtk_spin_button_get_value_as_int (GTK_SPIN_BUTTON (widget));
+}
+
+static void
+gamma_correct_clicked (GtkWidget *widget,
+                       gpointer   data)
+{
+  dds_write_vals.gamma_correct =
+    gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (widget));
+
+  gtk_widget_set_sensitive (srgb_chk,
+                            dds_write_vals.gamma_correct);
+  gtk_widget_set_sensitive (gamma_spin,
+                            dds_write_vals.gamma_correct &&
+                            ! dds_write_vals.srgb);
+}
+
+static void
+srgb_clicked (GtkWidget *widget,
+              gpointer   data)
+{
+  dds_write_vals.srgb =
+    gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (widget));
+
+  gtk_widget_set_sensitive (gamma_spin, !dds_write_vals.srgb);
+}
+
+static void
+gamma_changed (GtkWidget *widget,
+               gpointer   data)
+{
+  dds_write_vals.gamma =
+    gtk_spin_button_get_value (GTK_SPIN_BUTTON (widget));
+}
+
+static void
+alpha_coverage_clicked (GtkWidget *widget,
+                        gpointer   data)
+{
+  dds_write_vals.preserve_alpha_coverage =
+    gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (widget));
+
+  gtk_widget_set_sensitive (alpha_test_threshold_spin,
+                            dds_write_vals.preserve_alpha_coverage);
+}
+
+static void
+alpha_test_threshold_changed (GtkWidget *widget,
+                              gpointer   data)
+{
+  dds_write_vals.alpha_test_threshold =
+    gtk_spin_button_get_value (GTK_SPIN_BUTTON (widget));
+}
+
+static gint
+save_dialog (gint32 image_id,
+             gint32 drawable_id)
+{
+  GtkWidget *dlg;
+  GtkWidget *vbox;
+  GtkWidget *hbox;
+  GtkWidget *table;
+  GtkWidget *opt;
+  GtkWidget *check;
+  GtkWidget *spin;
+  GtkWidget *frame;
+  GimpImageBaseType basetype;
+
+  if (is_cubemap || is_volume || is_array)
+    dds_write_vals.savetype = DDS_SAVE_SELECTED_LAYER;
+
+  basetype = gimp_image_base_type (image_id);
+
+  dlg = gimp_dialog_new (_("Export as DDS"), "dds", NULL, GTK_WIN_POS_MOUSE,
+                         gimp_standard_help_func, SAVE_PROC,
+                         _("_Cancel"), GTK_RESPONSE_CANCEL,
+                         _("_Export"), GTK_RESPONSE_OK,
+                         NULL);
+
+  g_signal_connect (dlg, "response",
+                    G_CALLBACK (save_dialog_response),
+                    NULL);
+  g_signal_connect (dlg, "destroy",
+                    G_CALLBACK (gtk_main_quit),
+                    NULL);
+
+  gtk_window_set_resizable (GTK_WINDOW (dlg), FALSE);
+
+  vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 6);
+  gtk_container_set_border_width (GTK_CONTAINER (vbox), 12);
+  gtk_box_pack_start (GTK_BOX (gtk_dialog_get_content_area (GTK_DIALOG (dlg))),
+                      vbox, TRUE, TRUE, 0);
+  gtk_widget_show (vbox);
+
+  table = gtk_table_new (6, 2, 0);
+  gtk_widget_show (table);
+  gtk_box_pack_start (GTK_BOX (vbox), table, FALSE, FALSE, 0);
+  gtk_table_set_row_spacings (GTK_TABLE (table), 6);
+  gtk_table_set_col_spacings (GTK_TABLE (table), 8);
+
+  opt = string_value_combo_new (compression_strings,
+                                dds_write_vals.compression);
+  gimp_table_attach_aligned (GTK_TABLE (table), 0, 0,
+                             _("_Compression:"),
+                             0.0, 0.5,
+                             opt, 1, FALSE);
+
+  g_signal_connect (opt, "changed",
+                    G_CALLBACK (compression_selected),
+                    NULL);
+
+  compress_opt = opt;
+
+  check = gtk_check_button_new_with_mnemonic (_("Use _perceptual error metric"));
+  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (check),
+                                dds_write_vals.perceptual_metric);
+  gtk_table_attach (GTK_TABLE (table), check, 1, 2, 1, 2,
+                    GTK_FILL, 0, 0, 0);
+  gtk_widget_show (check);
+
+  g_signal_connect (check, "clicked",
+                    G_CALLBACK (toggle_clicked),
+                    &dds_write_vals.perceptual_metric);
+
+  pm_chk = check;
+
+  opt = string_value_combo_new (format_strings, dds_write_vals.format);
+  gimp_table_attach_aligned (GTK_TABLE (table), 0, 2,
+                             _("_Format:"),
+                             0.0, 0.5,
+                             opt, 1, FALSE);
+
+  g_signal_connect (opt, "changed",
+                    G_CALLBACK (string_value_combo_selected),
+                    &dds_write_vals.format);
+
+  gtk_widget_set_sensitive (opt, dds_write_vals.compression == DDS_COMPRESS_NONE);
+
+  format_opt = opt;
+
+  opt = string_value_combo_new (save_type_strings, dds_write_vals.savetype);
+  gimp_table_attach_aligned (GTK_TABLE (table), 0, 3,
+                             _("_Save:"),
+                             0.0, 0.5,
+                             opt, 1, FALSE);
+
+  g_signal_connect (opt, "changed",
+                    G_CALLBACK (savetype_selected),
+                    &image_id);
+
+  string_value_combo_set_item_sensitive (opt, DDS_SAVE_CUBEMAP, is_cubemap);
+  string_value_combo_set_item_sensitive (opt, DDS_SAVE_VOLUMEMAP, is_volume);
+  string_value_combo_set_item_sensitive (opt, DDS_SAVE_ARRAY, is_array);
+
+  check = gtk_check_button_new_with_mnemonic (_("Flip the image _vertically on export"));
+  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (check),
+                                dds_write_vals.flip_image);
+  gtk_table_attach (GTK_TABLE (table), check, 1, 2, 4, 5,
+                    GTK_FILL, 0, 0, 0);
+  gtk_widget_show (check);
+
+  g_signal_connect (check, "clicked",
+                    G_CALLBACK (toggle_clicked),
+                    &dds_write_vals.flip_image);
+
+  opt = string_value_combo_new (mipmap_strings, dds_write_vals.mipmaps);
+  gimp_table_attach_aligned (GTK_TABLE (table), 0, 5,
+                             _("_Mipmaps:"),
+                             0.0, 0.5,
+                             opt, 1, FALSE);
+
+  g_signal_connect (opt, "changed",
+                    G_CALLBACK (mipmaps_selected),
+                    &image_id);
+
+  string_value_combo_set_item_sensitive (opt, DDS_MIPMAP_EXISTING,
+                                         check_mipmaps (image_id,
+                                                        dds_write_vals.savetype));
+
+  mipmap_opt = opt;
+
+  string_value_combo_set_item_sensitive (opt, DDS_MIPMAP_EXISTING,
+                                         ! (is_volume || is_cubemap) &&
+                                         is_mipmap_chain_valid);
+
+
+  hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 8);
+  gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
+  gtk_widget_show (hbox);
+
+  check = gtk_check_button_new_with_label (_("Transparent index:"));
+  gtk_box_pack_start (GTK_BOX (hbox), check, FALSE, FALSE, 0);
+  gtk_widget_show (check);
+
+  g_signal_connect (check, "clicked",
+                    G_CALLBACK (transindex_clicked),
+                    NULL);
+
+  spin = gimp_spin_button_new
+    (GTK_ADJUSTMENT (gtk_adjustment_new (0, 0, 255, 1, 1, 0)), 1, 0);
+  gtk_box_pack_start (GTK_BOX (hbox), spin, TRUE, TRUE, 0);
+  gtk_spin_button_set_update_policy (GTK_SPIN_BUTTON (spin),
+                                     GTK_UPDATE_IF_VALID);
+  gtk_widget_show (spin);
+
+  g_signal_connect (spin, "value-changed",
+                    G_CALLBACK (transindex_changed),
+                    NULL);
+
+  g_object_set_data (G_OBJECT (check), "spin", spin);
+
+  if (basetype != GIMP_INDEXED)
+    {
+      gtk_widget_set_sensitive (check, FALSE);
+      gtk_widget_set_sensitive (spin, FALSE);
+    }
+  else if (dds_write_vals.transindex < 0)
+    {
+      gtk_widget_set_sensitive (spin, FALSE);
+    }
+  else if (dds_write_vals.transindex >= 0)
+    {
+      gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (check), TRUE);
+      gtk_spin_button_set_value (GTK_SPIN_BUTTON (spin),
+                                 dds_write_vals.transindex);
+    }
+
+  if (is_volume && dds_write_vals.savetype == DDS_SAVE_VOLUMEMAP)
+    {
+      dds_write_vals.compression = DDS_COMPRESS_NONE;
+      string_value_combo_set_active (compress_opt, DDS_COMPRESS_NONE);
+      gtk_widget_set_sensitive (compress_opt, FALSE);
+    }
+
+  frame = gimp_frame_new (_("Mipmap Options"));
+  gtk_box_pack_start (GTK_BOX (vbox), frame, FALSE, FALSE, 0);
+  gtk_widget_show (frame);
+
+  table = gtk_table_new (7, 2, 0);
+  gtk_table_set_row_spacings (GTK_TABLE (table), 6);
+  gtk_table_set_col_spacings (GTK_TABLE (table), 8);
+  gtk_container_add (GTK_CONTAINER (frame), table);
+  gtk_widget_show (table);
+
+  opt = string_value_combo_new (mipmap_filter_strings,
+                                dds_write_vals.mipmap_filter);
+  gimp_table_attach_aligned (GTK_TABLE (table), 0, 0,
+                             _("F_ilter:"),
+                             0.0, 0.5,
+                             opt, 1, FALSE);
+
+  g_signal_connect (opt, "changed",
+                    G_CALLBACK (string_value_combo_selected),
+                    &dds_write_vals.mipmap_filter);
+
+  mipmap_filter_opt = opt;
+
+  opt = string_value_combo_new (mipmap_wrap_strings,
+                                dds_write_vals.mipmap_wrap);
+  gimp_table_attach_aligned (GTK_TABLE (table), 0, 1,
+                             _("_Wrap mode:"),
+                             0.0, 0.5,
+                             opt, 1, FALSE);
+
+  g_signal_connect (opt, "changed",
+                    G_CALLBACK (string_value_combo_selected),
+                    &dds_write_vals.mipmap_wrap);
+
+  mipmap_wrap_opt = opt;
+
+  check = gtk_check_button_new_with_mnemonic (_("Appl_y gamma correction"));
+  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (check),
+                                dds_write_vals.gamma_correct &&
+                                dds_write_vals.mipmaps);
+  gtk_table_attach (GTK_TABLE (table), check, 1, 2, 2, 3,
+                    GTK_FILL, 0, 0, 0);
+  gtk_widget_show (check);
+
+  g_signal_connect (check, "clicked",
+                    G_CALLBACK (gamma_correct_clicked),
+                    NULL);
+
+  gamma_chk = check;
+
+  check = gtk_check_button_new_with_mnemonic (_("Use s_RGB colorspace"));
+  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (check),
+                                dds_write_vals.gamma_correct &&
+                                dds_write_vals.srgb);
+  gtk_table_attach (GTK_TABLE (table), check, 1, 2, 3, 4,
+                    GTK_FILL, 0, 0, 0);
+  gtk_widget_show (check);
+
+  g_signal_connect (check, "clicked",
+                    G_CALLBACK (srgb_clicked),
+                    NULL);
+
+  srgb_chk = check;
+
+  spin = gimp_spin_button_new
+    (GTK_ADJUSTMENT (gtk_adjustment_new (dds_write_vals.gamma,
+                                         1e-05, 100, 0.1, 0.5, 0)), 1, 1);
+  gtk_spin_button_set_update_policy (GTK_SPIN_BUTTON (spin), GTK_UPDATE_IF_VALID);
+  gimp_table_attach_aligned (GTK_TABLE (table), 0, 4,
+                             _("_Gamma:"),
+                             0.0, 0.5,
+                             spin, 1, FALSE);
+
+  g_signal_connect (spin, "value_changed",
+                    G_CALLBACK (gamma_changed),
+                    NULL);
+
+  gamma_spin = spin;
+
+  check = gtk_check_button_new_with_mnemonic (_("Preserve alpha _test coverage"));
+  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (check),
+                                dds_write_vals.preserve_alpha_coverage &&
+                                dds_write_vals.mipmaps);
+  gtk_table_attach (GTK_TABLE (table), check, 1, 2, 5, 6,
+                    GTK_FILL, 0, 0, 0);
+  gtk_widget_show (check);
+
+  g_signal_connect (check, "clicked",
+                    G_CALLBACK (alpha_coverage_clicked),
+                    NULL);
+
+  alpha_coverage_chk = check;
+
+  spin = gimp_spin_button_new
+    (GTK_ADJUSTMENT (gtk_adjustment_new (dds_write_vals.alpha_test_threshold,
+                                         0, 1, 0.01, 0.1, 0)), 1, 2);
+  gtk_spin_button_set_update_policy (GTK_SPIN_BUTTON (spin), GTK_UPDATE_IF_VALID);
+  gimp_table_attach_aligned (GTK_TABLE (table), 0, 6,
+                             _("_Alpha test threshold:"),
+                             0.0, 0.5,
+                             spin, 1, FALSE);
+
+  g_signal_connect (spin, "value_changed",
+                    G_CALLBACK (alpha_test_threshold_changed),
+                    NULL);
+
+  alpha_test_threshold_spin = spin;
+
+  gtk_widget_set_sensitive (mipmap_filter_opt,
+                            dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE);
+  gtk_widget_set_sensitive (mipmap_wrap_opt,
+                            dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE);
+  gtk_widget_set_sensitive (gamma_chk
+                            , dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE);
+  gtk_widget_set_sensitive (srgb_chk,
+                            (dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE) &&
+                            dds_write_vals.gamma_correct);
+  gtk_widget_set_sensitive (gamma_spin,
+                            (dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE) &&
+                            dds_write_vals.gamma_correct &&
+                            !dds_write_vals.srgb);
+  gtk_widget_set_sensitive (pm_chk,
+                            dds_write_vals.compression != DDS_COMPRESS_NONE);
+  gtk_widget_set_sensitive (alpha_coverage_chk,
+                            dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE);
+  gtk_widget_set_sensitive (alpha_test_threshold_spin,
+                            (dds_write_vals.mipmaps == DDS_MIPMAP_GENERATE) &&
+                            dds_write_vals.preserve_alpha_coverage);
+
+  gtk_widget_show (dlg);
+
+  runme = FALSE;
+
+  gtk_main ();
+
+  return runme;
+}