From 40070d899d551f4602c641b34fa0cbd1937cbf15 Mon Sep 17 00:00:00 2001
From: Cameron Cawley <[EMAIL REDACTED]>
Date: Sat, 12 Oct 2024 19:05:47 +0100
Subject: [PATCH] Refactor Blit_RGB555_ARGB1555 to be more generic
---
src/video/SDL_blit_N.c | 70 +++++++++++++++++++++++++++---------------
1 file changed, 45 insertions(+), 25 deletions(-)
diff --git a/src/video/SDL_blit_N.c b/src/video/SDL_blit_N.c
index 9727ba6ab707a..bd4e69e54f95a 100644
--- a/src/video/SDL_blit_N.c
+++ b/src/video/SDL_blit_N.c
@@ -1785,8 +1785,8 @@ static void Blit_RGB565_BGRA8888(SDL_BlitInfo * info)
#endif // SDL_HAVE_BLIT_N_RGB565
-// RGB555->ARGB1555, and BGR555->ABGR1555, SET_ALPHA
-static void Blit_RGB555_ARGB1555(SDL_BlitInfo *info)
+// blits 16 bit RGB<->RGBA with both surfaces having the same R,G,B fields
+static void Blit2to2MaskAlpha(SDL_BlitInfo *info)
{
int width = info->dst_w;
int height = info->dst_h;
@@ -1794,22 +1794,43 @@ static void Blit_RGB555_ARGB1555(SDL_BlitInfo *info)
int srcskip = info->src_skip;
Uint16 *dst = (Uint16 *)info->dst;
int dstskip = info->dst_skip;
+ const SDL_PixelFormatDetails *srcfmt = info->src_fmt;
const SDL_PixelFormatDetails *dstfmt = info->dst_fmt;
- Uint16 mask = ((Uint32)info->a >> (8 - dstfmt->Abits)) << dstfmt->Ashift;
+ if (dstfmt->Amask) {
+ // RGB->RGBA, SET_ALPHA
+ Uint16 mask = ((Uint32)info->a >> (8 - dstfmt->Abits)) << dstfmt->Ashift;
- while (height--) {
- /* *INDENT-OFF* */ // clang-format off
- DUFFS_LOOP_TRIVIAL(
- {
- *dst = *src | mask;
- ++dst;
- ++src;
- },
- width);
- /* *INDENT-ON* */ // clang-format on
- src = (Uint16 *)((Uint8 *)src + srcskip);
- dst = (Uint16 *)((Uint8 *)dst + dstskip);
+ while (height--) {
+ /* *INDENT-OFF* */ // clang-format off
+ DUFFS_LOOP_TRIVIAL(
+ {
+ *dst = *src | mask;
+ ++dst;
+ ++src;
+ },
+ width);
+ /* *INDENT-ON* */ // clang-format on
+ src = (Uint16 *)((Uint8 *)src + srcskip);
+ dst = (Uint16 *)((Uint8 *)dst + dstskip);
+ }
+ } else {
+ // RGBA->RGB, NO_ALPHA
+ Uint16 mask = srcfmt->Rmask | srcfmt->Gmask | srcfmt->Bmask;
+
+ while (height--) {
+ /* *INDENT-OFF* */ // clang-format off
+ DUFFS_LOOP_TRIVIAL(
+ {
+ *dst = *src & mask;
+ ++dst;
+ ++src;
+ },
+ width);
+ /* *INDENT-ON* */ // clang-format on
+ src = (Uint16 *)((Uint8 *)src + srcskip);
+ dst = (Uint16 *)((Uint8 *)dst + dstskip);
+ }
}
}
@@ -2742,11 +2763,6 @@ static const struct blit_table normal_blit_2[] = {
{ 0x0000F800, 0x000007E0, 0x0000001F, 4, 0x0000FF00, 0x00FF0000, 0xFF000000,
0, Blit_RGB565_BGRA8888, NO_ALPHA | COPY_ALPHA | SET_ALPHA },
#endif
- { 0x00007C00, 0x000003E0, 0x0000001F, 2, 0x00007C00, 0x000003E0, 0x0000001F,
- 0, Blit_RGB555_ARGB1555, SET_ALPHA },
- { 0x0000001F, 0x000003E0, 0x00007C00, 2, 0x0000001F, 0x000003E0, 0x00007C00,
- 0, Blit_RGB555_ARGB1555, SET_ALPHA },
-
// Default for 16-bit RGB source, used if no other blitter matches
{ 0, 0, 0, 0, 0, 0, 0, 0, BlitNtoN, 0 }
};
@@ -2884,21 +2900,25 @@ SDL_BlitFunc SDL_CalculateBlitN(SDL_Surface *surface)
}
if (blitfun == BlitNtoN) { // default C fallback catch-all. Slow!
- if (srcfmt->bytes_per_pixel == 4 &&
- dstfmt->bytes_per_pixel == 4 &&
+ if (srcfmt->bytes_per_pixel == dstfmt->bytes_per_pixel &&
srcfmt->Rmask == dstfmt->Rmask &&
srcfmt->Gmask == dstfmt->Gmask &&
srcfmt->Bmask == dstfmt->Bmask) {
if (a_need == COPY_ALPHA) {
if (srcfmt->Amask == dstfmt->Amask) {
- // Fastpath C fallback: 32bit RGBA<->RGBA blit with matching RGBA
+ // Fastpath C fallback: RGBA<->RGBA blit with matching RGBA
blitfun = SDL_BlitCopy;
} else {
blitfun = BlitNtoNCopyAlpha;
}
} else {
- // Fastpath C fallback: 32bit RGB<->RGBA blit with matching RGB
- blitfun = Blit4to4MaskAlpha;
+ if (srcfmt->bytes_per_pixel == 4) {
+ // Fastpath C fallback: 32bit RGB<->RGBA blit with matching RGB
+ blitfun = Blit4to4MaskAlpha;
+ } else if (srcfmt->bytes_per_pixel == 2) {
+ // Fastpath C fallback: 16bit RGB<->RGBA blit with matching RGB
+ blitfun = Blit2to2MaskAlpha;
+ }
}
} else if (a_need == COPY_ALPHA) {
blitfun = BlitNtoNCopyAlpha;