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Diffstat (limited to 'app/operations/layer-modes/gimpoperationerase.c')
| -rw-r--r-- | app/operations/layer-modes/gimpoperationerase.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/app/operations/layer-modes/gimpoperationerase.c b/app/operations/layer-modes/gimpoperationerase.c new file mode 100644 index 0000000..aae6eac --- /dev/null +++ b/app/operations/layer-modes/gimpoperationerase.c @@ -0,0 +1,214 @@ +/* GIMP - The GNU Image Manipulation Program + * Copyright (C) 1995 Spencer Kimball and Peter Mattis + * + * gimpoperationerase.c + * Copyright (C) 2008 Michael Natterer <mitch@gimp.org> + * 2012 Ville Sokk <ville.sokk@gmail.com> + * + * 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 3 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. If not, see <https://www.gnu.org/licenses/>. + */ + +#include "config.h" + +#include <gegl-plugin.h> + +#include "../operations-types.h" + +#include "gimpoperationerase.h" + + +static gboolean gimp_operation_erase_process (GeglOperation *op, + void *in, + void *layer, + void *mask, + void *out, + glong samples, + const GeglRectangle *roi, + gint level); + + +G_DEFINE_TYPE (GimpOperationErase, gimp_operation_erase, + GIMP_TYPE_OPERATION_LAYER_MODE) + + +static void +gimp_operation_erase_class_init (GimpOperationEraseClass *klass) +{ + GeglOperationClass *operation_class = GEGL_OPERATION_CLASS (klass); + GimpOperationLayerModeClass *layer_mode_class = GIMP_OPERATION_LAYER_MODE_CLASS (klass); + + gegl_operation_class_set_keys (operation_class, + "name", "gimp:erase", + "description", "GIMP erase mode operation", + NULL); + + layer_mode_class->process = gimp_operation_erase_process; +} + +static void +gimp_operation_erase_init (GimpOperationErase *self) +{ +} + +static gboolean +gimp_operation_erase_process (GeglOperation *op, + void *in_p, + void *layer_p, + void *mask_p, + void *out_p, + glong samples, + const GeglRectangle *roi, + gint level) +{ + GimpOperationLayerMode *layer_mode = (gpointer) op; + gfloat *in = in_p; + gfloat *out = out_p; + gfloat *layer = layer_p; + gfloat *mask = mask_p; + gfloat opacity = layer_mode->opacity; + const gboolean has_mask = mask != NULL; + + switch (layer_mode->composite_mode) + { + case GIMP_LAYER_COMPOSITE_UNION: + while (samples--) + { + gfloat layer_alpha; + gfloat new_alpha; + gint b; + + layer_alpha = layer[ALPHA] * opacity; + + if (has_mask) + layer_alpha *= (*mask); + + new_alpha = in[ALPHA] + layer_alpha - 2.0f * in[ALPHA] * layer_alpha; + + if (new_alpha != 0.0f) + { + gfloat ratio; + + ratio = (1.0f - in[ALPHA]) * layer_alpha / new_alpha; + + for (b = RED; b < ALPHA; b++) + { + out[b] = ratio * layer[b] + (1.0f - ratio) * in[b]; + } + } + else + { + for (b = RED; b < ALPHA; b++) + { + out[b] = in[b]; + } + } + + out[ALPHA] = new_alpha; + + in += 4; + layer += 4; + out += 4; + + if (has_mask) + mask ++; + } + break; + + case GIMP_LAYER_COMPOSITE_CLIP_TO_BACKDROP: + case GIMP_LAYER_COMPOSITE_AUTO: + while (samples--) + { + gfloat layer_alpha; + gfloat new_alpha; + gint b; + + layer_alpha = layer[ALPHA] * opacity; + + if (has_mask) + layer_alpha *= (*mask); + + new_alpha = (1.0f - layer_alpha) * in[ALPHA]; + + for (b = RED; b < ALPHA; b++) + { + out[b] = in[b]; + } + + out[ALPHA] = new_alpha; + + in += 4; + layer += 4; + out += 4; + + if (has_mask) + mask ++; + } + break; + + case GIMP_LAYER_COMPOSITE_CLIP_TO_LAYER: + while (samples--) + { + gfloat layer_alpha; + gfloat new_alpha; + const gfloat *src; + gint b; + + layer_alpha = layer[ALPHA] * opacity; + + if (has_mask) + layer_alpha *= (*mask); + + new_alpha = (1.0f - in[ALPHA]) * layer_alpha; + + src = layer; + + if (new_alpha == 0.0f) + src = in; + + for (b = RED; b < ALPHA; b++) + { + out[b] = src[b]; + } + + out[ALPHA] = new_alpha; + + in += 4; + layer += 4; + out += 4; + + if (has_mask) + mask ++; + } + break; + + case GIMP_LAYER_COMPOSITE_INTERSECTION: + while (samples--) + { + gint b; + + for (b = RED; b < ALPHA; b++) + { + out[b] = in[b]; + } + + out[ALPHA] = 0.0f; + + in += 4; + out += 4; + } + break; + } + + return TRUE; +} |