Merge pull request #418 from pygame/aaline-requires-alpha

draw.aaline should work with ARGB surfaces (like on mac).
pygame · Mar 19, 2018 · a29d7e4 · a29d7e4
2 parents 7561a36 + 1d02d61
commit a29d7e4
Show file tree

Hide file tree

Showing 2 changed files with 25 additions and 14 deletions.
diff --git a/docs/reST/ref/draw.rst b/docs/reST/ref/draw.rst
@@ -150,6 +150,6 @@ object around the draw calls.
    :alt: draw module example
 
    Example code for draw module.
-   
+
 .. literalinclude:: code_examples/draw_module_example.py
-   
+
diff --git a/src/draw.c b/src/draw.c
@@ -932,19 +932,18 @@ static int set_at(SDL_Surface* surf, int x, int y, Uint32 color)
     return 1;
 }
 
-
 #define DRAWPIX32(pixel,colorptr,br,blend) \
-    if(SDL_BYTEORDER == SDL_BIG_ENDIAN) color <<= 8; \
-    if(blend) { \
-        int x; \
-        float nbr = 1.0-br; \
-        x = colorptr[0]*br+pixel[0]*nbr; \
-        pixel[0]= (x>254) ? 255: x; \
-        x = colorptr[1]*br+pixel[1]*nbr; \
-        pixel[1]= (x>254) ? 255: x; \
-        x = colorptr[2]*br+pixel[2]*nbr; \
-        pixel[2]= (x>254) ? 255: x; \
-        if(hasalpha) pixel[3] = pixel[0]+(br*255) - (pixel[3]*br); \
+    if (blend) { \
+        SDL_GetRGBA(*pixel, surf->format, &pixel_r, &pixel_g, &pixel_b, &pixel_a); \
+        tmp_r = color_r * br + pixel_r * nbr; \
+        tmp_g = color_g * br + pixel_g * nbr; \
+        tmp_b = color_b * br + pixel_b * nbr; \
+        tmp_a = color_a * br + pixel_a * nbr; \
+        *((Uint32*)pixel) = SDL_MapRGBA(surf->format, \
+            (Uint8)((tmp_r>254) ? 255: tmp_r), \
+            (Uint8)((tmp_g>254) ? 255: tmp_g), \
+            (Uint8)((tmp_b>254) ? 255: tmp_b), \
+            (Uint8)((tmp_a>254) ? 255: tmp_a)); \
     } else { \
         pixel[0]=(Uint8)(colorptr[0]*br); \
         pixel[1]=(Uint8)(colorptr[1]*br); \
@@ -960,11 +959,23 @@ static void drawaaline(SDL_Surface* surf, Uint32 color, float x1, float y1, floa
     float swaptmp;
     int x, y, ix1, ix2, iy1, iy2;
     int pixx, pixy;
+
+    /* for D-RAWPIX32 */
+    int tmp_r, tmp_g, tmp_b, tmp_a;
+    float nbr = 0.0f;
+    Uint8 pixel_r, pixel_g, pixel_b, pixel_a;
+    Uint8 color_r, color_g, color_b, color_a;
+
     Uint8* pixel;
     Uint8* pm = (Uint8*)surf->pixels;
     Uint8* colorptr = (Uint8*)&color;
     const int hasalpha = surf->format->Amask;
 
+    if (hasalpha) {
+        SDL_GetRGBA(color, surf->format, &color_r, &color_g, &color_b, &color_a);
+    } else {
+        SDL_GetRGB(color, surf->format, &color_r, &color_g, &color_b);
+    }
     pixx = surf->format->BytesPerPixel;
     pixy = surf->pitch;