1 files changed, 110 insertions, 0 deletions
diff --git a/src/trace/imagemap-gdk.cpp b/src/trace/imagemap-gdk.cpp
new file mode 100644
index 0000000..9d47b3b
--- /dev/null
+++ b/src/trace/imagemap-gdk.cpp
@@ -0,0 +1,110 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/** @file
+ * TODO: insert short description here
+ *//*
+ * Authors: see git history
+ *
+ * Copyright (C) 2018 Authors
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+#include <cassert>
+#include "imagemap-gdk.h"
+
+namespace Inkscape {
+namespace Trace {
+
+GrayMap gdkPixbufToGrayMap(Glib::RefPtr<Gdk::Pixbuf> const &buf)
+{
+    int width     = buf->get_width();
+    int height    = buf->get_height();
+    int rowstride = buf->get_rowstride();
+    int nchannels = buf->get_n_channels();
+    auto data     = buf->get_pixels();
+
+    auto map = GrayMap(width, height);
+
+    for (int y = 0; y < height; y++) {
+        auto p = data + rowstride * y;
+        for (int x = 0; x < width; x++) {
+            int alpha = nchannels == 3 ? 255 : p[3];
+            int white = 3 * (255 - alpha);
+            unsigned long sample = (int)p[0] + (int)p[1] + (int)p[2];
+            unsigned long bright = sample * alpha / 256 + white;
+            map.setPixel(x, y, bright);
+            p += nchannels;
+        }
+    }
+
+    return map;
+}
+
+Glib::RefPtr<Gdk::Pixbuf> grayMapToGdkPixbuf(GrayMap const &map)
+{
+    auto buf = Gdk::Pixbuf::create(Gdk::COLORSPACE_RGB, false, 8, map.width, map.height);
+
+    int rowstride = buf->get_rowstride();
+    int nchannels = buf->get_n_channels();
+    auto data     = buf->get_pixels();
+
+    for (int y = 0; y < map.height; y++) {
+        auto p = data + rowstride * y;
+        for (int x = 0; x < map.width; x++) {
+            unsigned long pix = map.getPixel(x, y) / 3;
+            p[0] = p[1] = p[2] = pix & 0xff;
+            p += nchannels;
+        }
+    }
+
+    return buf;
+}
+
+RgbMap gdkPixbufToRgbMap(Glib::RefPtr<Gdk::Pixbuf> const &buf)
+{
+    int width     = buf->get_width();
+    int height    = buf->get_height();
+    int rowstride = buf->get_rowstride();
+    int nchannels = buf->get_n_channels();
+    auto data     = buf->get_pixels();
+
+    auto map = RgbMap(width, height);
+
+    for (int y = 0; y < height; y++) {
+        auto p = data + rowstride * y;
+        for (int x = 0; x < width; x++) {
+            int alpha = nchannels == 3 ? 255 : p[3];
+            int white = 255 - alpha;
+            unsigned char r = (int)p[0] * alpha / 256 + white;
+            unsigned char g = (int)p[1] * alpha / 256 + white;
+            unsigned char b = (int)p[2] * alpha / 256 + white;
+            map.setPixel(x, y, {r, g, b});
+            p += nchannels;
+        }
+    }
+
+    return map;
+}
+
+Glib::RefPtr<Gdk::Pixbuf> indexedMapToGdkPixbuf(IndexedMap const &map)
+{
+    auto buf = Gdk::Pixbuf::create(Gdk::COLORSPACE_RGB, false, 8, map.width, map.height);
+
+    auto data     = buf->get_pixels();
+    int rowstride = buf->get_rowstride();
+    int nchannels = buf->get_n_channels();
+
+    for (int y = 0; y < map.height; y++) {
+        auto p = data + rowstride * y;
+        for (int x = 0; x < map.width; x++) {
+            auto rgb = map.getPixelValue(x, y);
+            p[0] = rgb.r & 0xff;
+            p[1] = rgb.g & 0xff;
+            p[2] = rgb.b & 0xff;
+            p += nchannels;
+        }
+    }
+
+    return buf;
+}
+
+} // namespace Trace
+} // namespace Inkscape