diff options
| -rw-r--r-- | src/mesa/drivers/dri/i965/brw_wm_surface_state.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c index a74b2c7cc1e..f1976391b1a 100644 --- a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c +++ b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c @@ -566,7 +566,20 @@ brw_init_surface_formats(struct brw_context *brw) ctx->TextureFormatSupported[MESA_FORMAT_X8_Z24] = true; ctx->TextureFormatSupported[MESA_FORMAT_Z32_FLOAT] = true; ctx->TextureFormatSupported[MESA_FORMAT_Z32_FLOAT_X24S8] = true; - ctx->TextureFormatSupported[MESA_FORMAT_Z16] = true; + + /* It appears that Z16 is slower than Z24 (on Intel Ivybridge and newer + * hardware at least), so there's no real reason to prefer it unless you're + * under memory (not memory bandwidth) pressure. Our speculation is that + * this is due to either increased fragment shader execution from + * GL_LEQUAL/GL_EQUAL depth tests at the reduced precision, or due to + * increased depth stalls from a cacheline-based heuristic for detecting + * depth stalls. + * + * However, desktop GL 3.0+ require that you get exactly 16 bits when + * asking for DEPTH_COMPONENT16, so we have to respect that. + */ + if (_mesa_is_desktop_gl(ctx)) + ctx->TextureFormatSupported[MESA_FORMAT_Z16] = true; /* On hardware that lacks support for ETC1, we map ETC1 to RGBX * during glCompressedTexImage2D(). See intel_mipmap_tree::wraps_etc1. |