display: prefer 24-bit depth buffer on Intel over 16-bit

rdb · rdb · commit 84520ce21c91 · 2017-07-09T19:53:23.000+02:00
diff --git a/panda/src/display/frameBufferProperties.cxx b/panda/src/display/frameBufferProperties.cxx
@@ -581,9 +581,13 @@ get_quality(const FrameBufferProperties &reqs) const {
     }
   }
 
-  // Bonus for each depth bit.  Extra: 2 per bit.
+  // Bonus for each depth bit.  Extra: 8 per bit.
+  // Please note that the Intel Windows driver only gives extra depth in
+  // combination with a stencil buffer, so we need 8 extra depth bits to
+  // outweigh the penalty of 50 for the unwanted stencil buffer, otherwise we
+  // will end up only getting 16-bit depth.
   if (reqs._property[FBP_depth_bits] != 0) {
-    quality += 2 * _property[FBP_depth_bits];
+    quality += 8 * _property[FBP_depth_bits];
   }
 
   // Bonus for each multisample.  Extra: 2 per sample.

Original file line number	Diff line number	Diff line change
`@@ -581,9 +581,13 @@ get_quality(const FrameBufferProperties &reqs) const {`
`581`	`581`	`}`
`582`	`582`	`}`
`583`	`583`
`584`		`- // Bonus for each depth bit. Extra: 2 per bit.`
	`584`	`+ // Bonus for each depth bit. Extra: 8 per bit.`
	`585`	`+ // Please note that the Intel Windows driver only gives extra depth in`
	`586`	`+ // combination with a stencil buffer, so we need 8 extra depth bits to`
	`587`	`+ // outweigh the penalty of 50 for the unwanted stencil buffer, otherwise we`
	`588`	`+ // will end up only getting 16-bit depth.`
`585`	`589`	`if (reqs._property[FBP_depth_bits] != 0) {`
`586`		`- quality += 2 * _property[FBP_depth_bits];`
	`590`	`+ quality += 8 * _property[FBP_depth_bits];`
`587`	`591`	`}`
`588`	`592`
`589`	`593`	`// Bonus for each multisample. Extra: 2 per sample.`