diff options
| -rw-r--r-- | src/mesa/drivers/dri/i965/intel_pixel_read.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/src/mesa/drivers/dri/i965/intel_pixel_read.c b/src/mesa/drivers/dri/i965/intel_pixel_read.c index babf8ca0b18..15f9e38d2c0 100644 --- a/src/mesa/drivers/dri/i965/intel_pixel_read.c +++ b/src/mesa/drivers/dri/i965/intel_pixel_read.c @@ -155,6 +155,21 @@ intel_readpixels_tiled_memcpy(struct gl_context * ctx, dst_pitch = _mesa_image_row_stride(pack, width, format, type); + /* For a window-system renderbuffer, the buffer is actually flipped + * vertically, so we need to handle that. Since the detiling function + * can only really work in the forwards direction, we have to be a + * little creative. First, we compute the Y-offset of the first row of + * the renderbuffer (in renderbuffer coordinates). We then match that + * with the last row of the client's data. Finally, we give + * tiled_to_linear a negative pitch so that it walks through the + * client's data backwards as it walks through the renderbufer forwards. + */ + if (rb->Name == 0) { + yoffset = rb->Height - yoffset - height; + pixels += (ptrdiff_t) (height - 1) * dst_pitch; + dst_pitch = -dst_pitch; + } + /* We postponed printing this message until having committed to executing * the function. */ |