BlinkenLib

@@ -61,7 +61,13 @@ static void BlinkenGifSetPixel(ColorMapObject *pMap, int idx, int transparent,

 stBlinkenMovie *BlinkenGifLoad(const char *pFilename)

 {

   GifFileType *gif;

-  int height, width, frameCnt, frameIdx, i, y, x,

+  struct sPass { int ofs, stride; };

+  static struct sPass const passes_linear[] = { { 0, 1 }, { 0, 0 } };

+  static struct sPass const passes_interlaced[] = {

+    { 0, 8 }, { 4, 8 }, { 2, 4 }, { 1, 2 }

+  };

+  struct sPass const *pass;

+  int height, width, frameCnt, frameIdx, i, y, x, y1, x1,

       bg, disposal, delay, transp, idx;

   ColorMapObject *pGlobalMap, *pMap;

   SavedImage *pImg;

@@ -140,9 +146,11 @@ stBlinkenMovie *BlinkenGifLoad(const char *pFilename)

       // frames with no duration -> only effect on background

       pFrame = NULL;

     }

-    // FIXME: pDesc->Interlace > 0

-    for (y = pDesc->Top, i = 0; y < pDesc->Top + pDesc->Height; ++y) {

-      for (x = pDesc->Left; x < pDesc->Left + pDesc->Width; ++x, ++i) {

+    for (pass = pDesc->Interlace ? passes_interlaced : passes_linear;

+         pass->stride > 0; ++pass) {

+      for (y = pass->ofs, y1 = pDesc->Top + pass->ofs, i = 0;

+           y < pDesc->Height; y += pass->stride, y1 += pass->stride) {

+        for (x = 0, x1 = pDesc->Left; x < pDesc->Width; ++x, ++x1, ++i) {

           idx = pImg->RasterBits[i];

           switch (disposal) {

             // undefined

@@ -153,21 +161,22 @@ stBlinkenMovie *BlinkenGifLoad(const char *pFilename)

             case 7:

             // do not dispose -> draw to frame and update background

             case 1:

-            BlinkenGifSetPixel(pMap, idx, transp, pFrame, y, x);

-            BlinkenGifSetPixel(pMap, idx, transp, pBack, y, x);

+              BlinkenGifSetPixel(pMap, idx, transp, pFrame, y1, x1);

+              BlinkenGifSetPixel(pMap, idx, transp, pBack, y1, x1);

               break;

             // restore background -> draw to frame and reset background

             case 2:

-            BlinkenGifSetPixel(pMap, idx, transp, pFrame, y, x);

-            BlinkenGifSetPixel(pMap, bg, transp, pBack, y, x);

+              BlinkenGifSetPixel(pMap, idx, transp, pFrame, y1, x1);

+              BlinkenGifSetPixel(pMap, bg, transp, pBack, y1, x1);

               break;

             // restore previous -> draw to frame only

             case 3:

-            BlinkenGifSetPixel(pMap, idx, transp, pFrame, y, x);

+              BlinkenGifSetPixel(pMap, idx, transp, pFrame, y1, x1);

               break;

-        }

-      }

-    }

+          } // switch disposal

+        } // for x

+      } // for y

+    } // for pass

     // append frame to movie

     if (pFrame) {