From a988ce55444d421850d5fb8593703b5e83b27be7 Mon Sep 17 00:00:00 2001
From: Sylvain <[EMAIL REDACTED]>
Date: Fri, 28 Jan 2022 17:24:59 +0100
Subject: [PATCH] Fixed bug #964 - SDL_RenderCopy stretch loses proportion on
viewport boundaries
---
src/render/software/SDL_render_sw.c | 19 ++++++++++++++++++-
1 file changed, 18 insertions(+), 1 deletion(-)
diff --git a/src/render/software/SDL_render_sw.c b/src/render/software/SDL_render_sw.c
index 7a2aac295c4..0eb9b513b47 100644
--- a/src/render/software/SDL_render_sw.c
+++ b/src/render/software/SDL_render_sw.c
@@ -823,7 +823,24 @@ SW_RunCommandQueue(SDL_Renderer * renderer, SDL_RenderCommand *cmd, void *vertic
* to avoid potentially frequent RLE encoding/decoding.
*/
SDL_SetSurfaceRLE(surface, 0);
- SDL_PrivateUpperBlitScaled(src, srcrect, surface, dstrect, texture->scaleMode);
+
+ /* Prevent to do scaling + clipping on viewport boundaries as it may lose proportion */
+ if (dstrect->x < 0 || dstrect->y < 0 || dstrect->x + dstrect->w > surface->w || dstrect->y + dstrect->h > surface->h) {
+ SDL_Surface *tmp = SDL_CreateRGBSurfaceWithFormat(0, dstrect->w, dstrect->h, 0, src->format->format);
+ /* Scale to an intermediate surface, then blit */
+ if (tmp) {
+ SDL_Rect r;
+ r.x = 0;
+ r.y = 0;
+ r.w = dstrect->w;
+ r.h = dstrect->h;
+ SDL_PrivateUpperBlitScaled(src, srcrect, tmp, &r, texture->scaleMode);
+ SDL_BlitSurface(tmp, NULL, surface, dstrect);
+ SDL_FreeSurface(tmp);
+ }
+ } else{
+ SDL_PrivateUpperBlitScaled(src, srcrect, surface, dstrect, texture->scaleMode);
+ }
}
break;
}