summaryrefslogtreecommitdiffstats
path: root/src/mesa/drivers/common/meta.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/mesa/drivers/common/meta.c')
-rw-r--r--src/mesa/drivers/common/meta.c14
1 files changed, 14 insertions, 0 deletions
diff --git a/src/mesa/drivers/common/meta.c b/src/mesa/drivers/common/meta.c
index 979926a7e8f..0e58aeca3f5 100644
--- a/src/mesa/drivers/common/meta.c
+++ b/src/mesa/drivers/common/meta.c
@@ -2691,12 +2691,26 @@ copy_tex_image(struct gl_context *ctx, GLuint dims, GLenum target, GLint level,
GLenum format, type;
GLint bpp;
void *buf;
+ struct gl_renderbuffer *read_rb = ctx->ReadBuffer->_ColorReadBuffer;
texObj = _mesa_get_current_tex_object(ctx, target);
texImage = _mesa_get_tex_image(ctx, texObj, target, level);
/* Choose format/type for temporary image buffer */
format = _mesa_base_tex_format(ctx, internalFormat);
+
+ if (format == GL_LUMINANCE &&
+ _mesa_get_format_base_format(read_rb->Format) != GL_LUMINANCE) {
+ /* The glReadPixels() path will convert RGB to luminance by
+ * summing R+G+B. glCopyTexImage() is supposed to behave as
+ * glCopyPixels, which doesn't do that change, and instead
+ * leaves it up to glTexImage which converts RGB to luminance by
+ * just taking the R channel. To avoid glReadPixels() trashing
+ * our data, use RGBA for our temporary image.
+ */
+ format = GL_RGBA;
+ }
+
type = get_temp_image_type(ctx, format);
bpp = _mesa_bytes_per_pixel(format, type);
if (bpp <= 0) {