dri: add a way to request that modes have matching color/zs depths

Some GPUs, notably nv3x/nv4x can't render to mismatched color/zs
framebuffer depths. Fallbacks can be done by the driver, with shadow
surfaces, but no reason to encourage applications to select non-matching
glx visuals.

Signed-off-by: Ilia Mirkin <[email protected]>
Reviewed-by: Marek Olšák <[email protected]>

1 files changed, 18 insertions, 3 deletions

diff --git a/src/mesa/drivers/dri/common/utils.c b/src/mesa/drivers/dri/common/utils.c
index 4b2e89c6ae3..c37d446a1e4 100644
--- a/src/mesa/drivers/dri/common/utils.c
+++ b/src/mesa/drivers/dri/common/utils.c
@@ -143,8 +143,10 @@ driGetRendererString( char * buffer, const char * hardware_name,
  * \param msaa_samples  Array of msaa sample count. 0 represents a visual
  *                      without a multisample buffer.
  * \param num_msaa_modes Number of entries in \c msaa_samples.
- * \param visType       GLX visual type.  Usually either \c GLX_TRUE_COLOR or
- *                      \c GLX_DIRECT_COLOR.
+ * \param enable_accum  Add an accum buffer to the configs
+ * \param color_depth_match Whether the color depth must match the zs depth
+ *                          This forces 32-bit color to have 24-bit depth, and
+ *                          16-bit color to have 16-bit depth.
  * 
  * \returns
  * Pointer to any array of pointers to the \c __DRIconfig structures created
@@ -158,7 +160,7 @@ driCreateConfigs(mesa_format format,
 		 unsigned num_depth_stencil_bits,
 		 const GLenum * db_modes, unsigned num_db_modes,
 		 const uint8_t * msaa_samples, unsigned num_msaa_modes,
-		 GLboolean enable_accum)
+		 GLboolean enable_accum, GLboolean color_depth_match)
 {
    static const uint32_t masks_table[][4] = {
       /* MESA_FORMAT_B5G6R5_UNORM */
@@ -236,6 +238,19 @@ driCreateConfigs(mesa_format format,
 	for ( i = 0 ; i < num_db_modes ; i++ ) {
 	    for ( h = 0 ; h < num_msaa_modes; h++ ) {
 	    	for ( j = 0 ; j < num_accum_bits ; j++ ) {
+		    if (color_depth_match &&
+			(depth_bits[k] || stencil_bits[k])) {
+			/* Depth can really only be 0, 16, 24, or 32. A 32-bit
+			 * color format still matches 24-bit depth, as there
+			 * is an implicit 8-bit stencil. So really we just
+			 * need to make sure that color/depth are both 16 or
+			 * both non-16.
+			 */
+			if ((depth_bits[k] + stencil_bits[k] == 16) !=
+			    (red_bits + green_bits + blue_bits + alpha_bits == 16))
+			    continue;
+		    }
+
 		    *c = malloc (sizeof **c);
 		    modes = &(*c)->modes;
 		    c++;