From f272e1dd85a9c540792705bd98ae7fad566369b4 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <slouken@libsdl.org>
Date: Sun, 4 Oct 2009 04:03:37 +0000
Subject: [PATCH] Adam Strzelecki to SDL

Since current DirectFB implementation is incomplete for YUV surfaces (actually causes segmentation faults when trying Lock and use YUV planar textures) I decided to fix it a bit.
Here's a patch that should make DirectFB properly support YUV both packed and planar (3 planes).

(1) Removed SDL_BYTESPERPIXEL at all in favor of DFB_BYTES_PER_PIXEL(SDLToDFBPixelFormat(fmt)) which does return always proper BPP for YUVs too, coz SDL_BYTESPERPIXEL returns incorrect values for FOURCCs
(2) Fixed data->pixels allocation for planar YUVs in CreateTexture, it should allocate 150% more space
(3) Copy other planes for planar YUVs in UpdateTexture
(4) Moved checking if format is supported at all with DirectFB on CreateTexture at the beginning of the code

Waiting for comments,
--
Adam Strzelecki | nanoant.com
---
 src/video/directfb/SDL_DirectFB_render.c | 50 ++++++++++++++++++------
 1 file changed, 37 insertions(+), 13 deletions(-)

diff --git a/src/video/directfb/SDL_DirectFB_render.c b/src/video/directfb/SDL_DirectFB_render.c
index 383fdd6e0..e11014f62 100644
--- a/src/video/directfb/SDL_DirectFB_render.c
+++ b/src/video/directfb/SDL_DirectFB_render.c
@@ -499,12 +499,20 @@ DirectFB_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)
     DirectFB_TextureData *data;
     DFBResult ret;
     DFBSurfaceDescription dsc;
+    DFBSurfacePixelFormat pixelformat;
 
     SDL_DFB_CALLOC(data, 1, sizeof(*data));
     texture->driverdata = data;
 
+    /* find the right pixelformat */
+    pixelformat = SDLToDFBPixelFormat(texture->format);
+    if (pixelformat == DSPF_UNKNOWN) {
+        SDL_SetError("Unknown pixel format %d\n", data->format);
+        goto error;
+    }
+
     data->format = texture->format;
-    data->pitch = (texture->w * SDL_BYTESPERPIXEL(data->format));
+    data->pitch = texture->w * DFB_BYTES_PER_PIXEL(pixelformat);
 
     if (DirectFB_AcquireVidLayer(renderer, texture) != 0) {
         /* fill surface description */
@@ -525,14 +533,7 @@ DirectFB_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)
             dsc.caps |= DSCAPS_VIDEOONLY;
 #endif
 
-        /* find the right pixelformat */
-
-        dsc.pixelformat = SDLToDFBPixelFormat(data->format);
-        if (dsc.pixelformat == DSPF_UNKNOWN) {
-            SDL_SetError("Unknown pixel format %d\n", data->format);
-            goto error;
-        }
-
+        dsc.pixelformat = pixelformat;
         data->pixels = NULL;
 
         /* Create the surface */
@@ -550,8 +551,13 @@ DirectFB_CreateTexture(SDL_Renderer * renderer, SDL_Texture * texture)
 #endif
 
     if (texture->access == SDL_TEXTUREACCESS_STREAMING) {
-        data->pitch = texture->w * SDL_BYTESPERPIXEL(texture->format);
-        SDL_DFB_CALLOC(data->pixels, 1, texture->h * data->pitch);
+        /* 3 plane YUVs return 1 bpp, but we need more space for other planes */
+        if(texture->format == SDL_PIXELFORMAT_YV12 ||
+           texture->format == SDL_PIXELFORMAT_IYUV) {
+            SDL_DFB_CALLOC(data->pixels, 1, (texture->h * data->pitch * 3 + texture->h * data->pitch * 3 % 2) / 2);
+        } else {
+            SDL_DFB_CALLOC(data->pixels, 1, texture->h * data->pitch);
+        }
     }
 
     return 0;
@@ -726,6 +732,24 @@ DirectFB_UpdateTexture(SDL_Renderer * renderer, SDL_Texture * texture,
         src += pitch;
         dst += dpitch;
     }
+    /* copy other planes for 3 plane formats */
+    if (texture->format == SDL_PIXELFORMAT_YV12 ||
+        texture->format == SDL_PIXELFORMAT_IYUV) {
+        src = (Uint8 *) pixels + texture->h * pitch;
+        dst = (Uint8 *) dpixels + texture->h * dpitch + rect->y * dpitch / 4 + rect->x * bpp / 2;
+        for (row = 0; row < rect->h / 2; ++row) {
+            SDL_memcpy(dst, src, length / 2);
+            src += pitch / 2;
+            dst += dpitch / 2;
+        }
+        src = (Uint8 *) pixels + texture->h * pitch + texture->h * pitch / 4;
+        dst = (Uint8 *) dpixels + texture->h * dpitch + texture->h * dpitch / 4 + rect->y * dpitch / 4 + rect->x * bpp / 2;
+        for (row = 0; row < rect->h / 2; ++row) {
+            SDL_memcpy(dst, src, length / 2);
+            src += pitch / 2;
+            dst += dpitch / 2;
+        }
+    }
     SDL_DFB_CHECKERR(data->surface->Unlock(data->surface));
     return 0;
   error:
@@ -759,7 +783,7 @@ DirectFB_LockTexture(SDL_Renderer * renderer, SDL_Texture * texture,
         *pixels =
             (void *) ((Uint8 *) texturedata->pixels +
                       rect->y * texturedata->pitch +
-                      rect->x * SDL_BYTESPERPIXEL(texture->format));
+                      rect->x * DFB_BYTES_PER_PIXEL(SDLToDFBPixelFormat(texture->format)));
         *pitch = texturedata->pitch;
     }
     return 0;
@@ -916,7 +940,7 @@ DirectFB_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,
         if (texturedata->dirty.list) {
             SDL_DirtyRect *dirty;
             void *pixels;
-            int bpp = SDL_BYTESPERPIXEL(texture->format);
+            int bpp = DFB_BYTES_PER_PIXEL(SDLToDFBPixelFormat(texture->format));
             int pitch = texturedata->pitch;
 
             for (dirty = texturedata->dirty.list; dirty; dirty = dirty->next) {