From b2db570ce9dfc70c6bef4b70f5f9a24bbaf3d59f Mon Sep 17 00:00:00 2001
From: Sylvain <sylvain.becker@gmail.com>
Date: Wed, 16 Mar 2022 18:09:40 +0100
Subject: [PATCH] SDL_triangle_blit_slow: sync code with SDL_blit_slow to
 handle ARGB2101010

---
 src/render/software/SDL_triangle.c | 57 ++++++++++++++++++++++--------
 1 file changed, 43 insertions(+), 14 deletions(-)

diff --git a/src/render/software/SDL_triangle.c b/src/render/software/SDL_triangle.c
index ce003e169..694cb4d91 100644
--- a/src/render/software/SDL_triangle.c
+++ b/src/render/software/SDL_triangle.c
@@ -718,6 +718,21 @@ end:
 }
 
 
+#define FORMAT_ALPHA      0
+#define FORMAT_NO_ALPHA  -1
+#define FORMAT_2101010    1
+#define FORMAT_HAS_ALPHA(format)        format == 0
+#define FORMAT_HAS_NO_ALPHA(format)     format < 0
+static int SDL_INLINE detect_format(SDL_PixelFormat *pf) {
+    if (pf->format == SDL_PIXELFORMAT_ARGB2101010) {
+        return FORMAT_2101010;
+    } else if (pf->Amask) {
+        return FORMAT_ALPHA;
+    } else {
+        return FORMAT_NO_ALPHA;
+    }
+}
+
 static void
 SDL_BlitTriangle_Slow(SDL_BlitInfo *info,
         SDL_Point s2_x_area, SDL_Rect dstrect, int area, int bias_w0, int bias_w1, int bias_w2,
@@ -738,25 +753,32 @@ SDL_BlitTriangle_Slow(SDL_BlitInfo *info,
     SDL_PixelFormat *dst_fmt = info->dst_fmt;
     int srcbpp = src_fmt->BytesPerPixel;
     int dstbpp = dst_fmt->BytesPerPixel;
+    int srcfmt_val;
+    int dstfmt_val;
     Uint32 rgbmask = ~src_fmt->Amask;
     Uint32 ckey = info->colorkey & rgbmask;
 
     Uint8 *dst_ptr = info->dst;
     int dst_pitch = info->dst_pitch;;
 
+    srcfmt_val = detect_format(src_fmt);
+    dstfmt_val = detect_format(dst_fmt);
+
     TRIANGLE_BEGIN_LOOP
     {
         Uint8 *src;
         Uint8 *dst = dptr;
         TRIANGLE_GET_TEXTCOORD
         src = (info->src + (srcy * info->src_pitch) + (srcx * srcbpp));
-        if (src_fmt->Amask) {
-            DISEMBLE_RGBA(src, srcbpp, src_fmt, srcpixel, srcR, srcG,
-                          srcB, srcA);
-        } else {
-            DISEMBLE_RGB(src, srcbpp, src_fmt, srcpixel, srcR, srcG,
-                         srcB);
+        if (FORMAT_HAS_ALPHA(srcfmt_val)) {
+            DISEMBLE_RGBA(src, srcbpp, src_fmt, srcpixel, srcR, srcG, srcB, srcA);
+        } else if (FORMAT_HAS_NO_ALPHA(srcfmt_val)) {
+            DISEMBLE_RGB(src, srcbpp, src_fmt, srcpixel, srcR, srcG, srcB);
             srcA = 0xFF;
+        } else {
+            /* SDL_PIXELFORMAT_ARGB2101010 */
+            srcpixel = *((Uint32 *)(src));
+            RGBA_FROM_ARGB2101010(srcpixel, srcR, srcG, srcB, srcA);
         }
         if (flags & SDL_COPY_COLORKEY) {
             /* srcpixel isn't set for 24 bpp */
@@ -768,13 +790,15 @@ SDL_BlitTriangle_Slow(SDL_BlitInfo *info,
                 continue;
             }
         }
-        if (dst_fmt->Amask) {
-            DISEMBLE_RGBA(dst, dstbpp, dst_fmt, dstpixel, dstR, dstG,
-                          dstB, dstA);
-        } else {
-            DISEMBLE_RGB(dst, dstbpp, dst_fmt, dstpixel, dstR, dstG,
-                         dstB);
+        if (FORMAT_HAS_ALPHA(dstfmt_val)) {
+            DISEMBLE_RGBA(dst, dstbpp, dst_fmt, dstpixel, dstR, dstG, dstB, dstA);
+        } else if (FORMAT_HAS_NO_ALPHA(dstfmt_val)) {
+            DISEMBLE_RGB(dst, dstbpp, dst_fmt, dstpixel, dstR, dstG, dstB);
             dstA = 0xFF;
+        } else {
+            /* SDL_PIXELFORMAT_ARGB2101010 */
+            dstpixel = *((Uint32 *)(dst));
+            RGBA_FROM_ARGB2101010(dstpixel, dstR, dstG, dstB, dstA);
         }
 
         if (! is_uniform) {
@@ -845,10 +869,15 @@ SDL_BlitTriangle_Slow(SDL_BlitInfo *info,
                 dstA = 255;
             break;
         }
-        if (dst_fmt->Amask) {
+        if (FORMAT_HAS_ALPHA(dstfmt_val)) {
             ASSEMBLE_RGBA(dst, dstbpp, dst_fmt, dstR, dstG, dstB, dstA);
-        } else {
+        } else if (FORMAT_HAS_NO_ALPHA(dstfmt_val)) {
             ASSEMBLE_RGB(dst, dstbpp, dst_fmt, dstR, dstG, dstB);
+        } else {
+            /* SDL_PIXELFORMAT_ARGB2101010 */
+            Uint32 pixel;
+            ARGB2101010_FROM_RGBA(pixel, dstR, dstG, dstB, dstA);
+            *(Uint32 *)dst = pixel;
         }
     }
     TRIANGLE_END_LOOP