Add PackedPixelMap to make pixbuf->pixel array conversion much cleaner. Also make certain that packed pixels are unsigned long.

(bzr r294)

1 files changed, 81 insertions, 0 deletions

diff --git a/src/trace/imagemap-gdk.cpp b/src/trace/imagemap-gdk.cpp
index 93a1d05aa..e217dd619 100644
--- a/src/trace/imagemap-gdk.cpp
+++ b/src/trace/imagemap-gdk.cpp
@@ -81,6 +81,87 @@ GdkPixbuf *grayMapToGdkPixbuf(GrayMap *grayMap)
 
 
 /*#########################################################################
+## P A C K E D    P I X E L    M A P
+#########################################################################*/
+
+PackedPixelMap *gdkPixbufToPackedPixelMap(GdkPixbuf *buf)
+{
+    if (!buf)
+        return NULL;
+
+    int width       = gdk_pixbuf_get_width(buf);
+    int height      = gdk_pixbuf_get_height(buf);
+    guchar *pixdata = gdk_pixbuf_get_pixels(buf);
+    int rowstride   = gdk_pixbuf_get_rowstride(buf);
+    int n_channels  = gdk_pixbuf_get_n_channels(buf);
+
+    PackedPixelMap *ppMap = PackedPixelMapCreate(width, height);
+    if (!ppMap)
+        return NULL;
+
+    //### Fill in the cells with RGB values
+    int x,y;
+    int row  = 0;
+    for (y=0 ; y<height ; y++)
+        {
+        guchar *p = pixdata + row;
+        for (x=0 ; x<width ; x++)
+            {
+            int alpha = (int)p[3];
+            int white = 255 - alpha;
+            int r     = (int)p[0];  r = r * alpha / 256 + white;
+            int g     = (int)p[1];  g = g * alpha / 256 + white;
+            int b     = (int)p[2];  b = b * alpha / 256 + white;
+
+            ppMap->setPixel(ppMap, x, y, r, g, b);
+            p += n_channels;
+            }
+        row += rowstride;
+        }
+
+    return ppMap;
+}
+
+GdkPixbuf *packedPixelMapToGdkPixbuf(PackedPixelMap *ppMap)
+{
+    if (!ppMap)
+        return NULL;
+
+    guchar *pixdata = (guchar *)
+          malloc(sizeof(guchar) * ppMap->width * ppMap->height * 3);
+    if (!pixdata)
+        return NULL;
+
+    int n_channels = 3;
+    int rowstride  = ppMap->width * 3;
+
+    GdkPixbuf *buf = gdk_pixbuf_new_from_data(pixdata, GDK_COLORSPACE_RGB,
+                        0, 8, ppMap->width, ppMap->height,
+                        rowstride, NULL, NULL);
+
+    //### Fill in the cells with RGB values
+    int x,y;
+    int row  = 0;
+    for (y=0 ; y<ppMap->height ; y++)
+        {
+        guchar *p = pixdata + row;
+        for (x=0 ; x<ppMap->width ; x++)
+            {
+            unsigned long rgb = ppMap->getPixel(ppMap, x, y);
+            p[0] = (rgb >> 16) & 0xff;
+            p[1] = (rgb >>  8) & 0xff;
+            p[2] = (rgb      ) & 0xff;
+            p += n_channels;
+            }
+        row += rowstride;
+        }
+
+    return buf;
+}
+
+
+
+/*#########################################################################
 ## R G B   M A P
 #########################################################################*/