[Mesa-dev] [PATCH] i965: expose sRGB visuals and EGL_KHR_gl_colorspace

[Tapani Pälli]

Patch exposes sRGB visuals and adds DRI integer query support for
__DRI2_RENDERER_HAS_FRAMEBUFFER_SRGB. Further changes make sure that
we mark if the app explicitly wanted sRGB and for these framebuffers
we don't turn sRGB off in intel_gles3_srgb_workaround. This way we
keep compatibility for existing applications relying on default sRGB
and only add more visual support.

With this change, following dEQP tests start to pass:

   dEQP-EGL.functional.wide_color.window_8888_colorspace_srgb
   dEQP-EGL.functional.wide_color.pbuffer_8888_colorspace_srgb

Signed-off-by: Tapani Pälli <tapani.palli at intel.com>
---

I did see following tests fail during CI run:

 ES31-CTS.functional.blend_equation_advanced.srgb.colorburn.hswm64
 ES31-CTS.functional.blend_equation_advanced.basic.colordodge.hswm64

However they don't seem to fail on non-hsw, so I'm not sure if this is
really a regression here? I saw that Ken has been burning some colors
before so I've CC:d him.

Note, this might have some effect on following bug:

https://bugs.freedesktop.org/show_bug.cgi?id=102503

For me SuperTuxKart was working when testing (!) But it could be I was
testing a wrong version.

 src/mesa/drivers/dri/i965/brw_context.c  | 16 ++++++++++------
 src/mesa/drivers/dri/i965/intel_fbo.h    |  5 +++++
 src/mesa/drivers/dri/i965/intel_screen.c | 12 ++++++++++++
 3 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_context.c b/src/mesa/drivers/dri/i965/brw_context.c
index 6441311d47..a8e39e3bb6 100644
--- a/src/mesa/drivers/dri/i965/brw_context.c
+++ b/src/mesa/drivers/dri/i965/brw_context.c
@@ -1112,8 +1112,8 @@ intelUnbindContext(__DRIcontext * driContextPriv)
  *
  * Unfortunately, renderbuffer setup happens before a context is created.  So
  * in intel_screen.c we always set up sRGB, and here, if you're a GLES2/3
- * context (without an sRGB visual, though we don't have sRGB visuals exposed
- * yet), we go turn that back off before anyone finds out.
+ * context (without an sRGB visual), we go turn that back off before anyone
+ * finds out.
  */
 static void
 intel_gles3_srgb_workaround(struct brw_context *brw,
@@ -1124,15 +1124,19 @@ intel_gles3_srgb_workaround(struct brw_context *brw,
    if (_mesa_is_desktop_gl(ctx) || !fb->Visual.sRGBCapable)
       return;
 
-   /* Some day when we support the sRGB capable bit on visuals available for
-    * GLES, we'll need to respect that and not disable things here.
-    */
-   fb->Visual.sRGBCapable = false;
    for (int i = 0; i < BUFFER_COUNT; i++) {
       struct gl_renderbuffer *rb = fb->Attachment[i].Renderbuffer;
+
+      /* Check if sRGB was specifically asked for. */
+      struct intel_renderbuffer *irb = intel_get_renderbuffer(fb, i);
+      if (irb && irb->explicit_srgb)
+         return;
+
       if (rb)
          rb->Format = _mesa_get_srgb_format_linear(rb->Format);
    }
+   /* Disable sRGB from framebuffers that are not compatible. */
+   fb->Visual.sRGBCapable = false;
 }
 
 GLboolean
diff --git a/src/mesa/drivers/dri/i965/intel_fbo.h b/src/mesa/drivers/dri/i965/intel_fbo.h
index 1e2494286b..c8c2ed9a1b 100644
--- a/src/mesa/drivers/dri/i965/intel_fbo.h
+++ b/src/mesa/drivers/dri/i965/intel_fbo.h
@@ -116,6 +116,11 @@ struct intel_renderbuffer
     * for the duration of a mapping.
     */
    bool singlesample_mt_is_tmp;
+
+   /**
+    * Application specifically asked for a sRGB visual.
+    */
+   bool explicit_srgb;
 };
 
 
diff --git a/src/mesa/drivers/dri/i965/intel_screen.c b/src/mesa/drivers/dri/i965/intel_screen.c
index d39509bcb8..79cc962ab1 100644
--- a/src/mesa/drivers/dri/i965/intel_screen.c
+++ b/src/mesa/drivers/dri/i965/intel_screen.c
@@ -1341,6 +1341,9 @@ brw_query_renderer_integer(__DRIscreen *dri_screen,
    case __DRI2_RENDERER_HAS_TEXTURE_3D:
       value[0] = 1;
       return 0;
+   case __DRI2_RENDERER_HAS_FRAMEBUFFER_SRGB:
+      value[0] = screen->mesa_format_supports_render[MESA_FORMAT_B8G8R8A8_SRGB];
+      return 0;
    default:
       return driQueryRendererIntegerCommon(dri_screen, param, value);
    }
@@ -1486,12 +1489,16 @@ intelCreateBuffer(__DRIscreen *dri_screen,
       fb->Visual.samples = num_samples;
    }
 
+   bool is_srgb = false;
+
    if (mesaVis->redBits == 5) {
       rgbFormat = mesaVis->redMask == 0x1f ? MESA_FORMAT_R5G6B5_UNORM
                                            : MESA_FORMAT_B5G6R5_UNORM;
    } else if (mesaVis->sRGBCapable) {
       rgbFormat = mesaVis->redMask == 0xff ? MESA_FORMAT_R8G8B8A8_SRGB
                                            : MESA_FORMAT_B8G8R8A8_SRGB;
+      /* mesaVis->sRGBCapable was set, user is asking for sRGB */
+      is_srgb = true;
    } else if (mesaVis->alphaBits == 0) {
       rgbFormat = mesaVis->redMask == 0xff ? MESA_FORMAT_R8G8B8X8_UNORM
                                            : MESA_FORMAT_B8G8R8X8_UNORM;
@@ -1504,10 +1511,12 @@ intelCreateBuffer(__DRIscreen *dri_screen,
    /* setup the hardware-based renderbuffers */
    rb = intel_create_winsys_renderbuffer(screen, rgbFormat, num_samples);
    _mesa_attach_and_own_rb(fb, BUFFER_FRONT_LEFT, &rb->Base.Base);
+   rb->explicit_srgb = is_srgb ? true : false;
 
    if (mesaVis->doubleBufferMode) {
       rb = intel_create_winsys_renderbuffer(screen, rgbFormat, num_samples);
       _mesa_attach_and_own_rb(fb, BUFFER_BACK_LEFT, &rb->Base.Base);
+      rb->explicit_srgb = is_srgb ? true : false;
    }
 
    /*
@@ -1854,6 +1863,9 @@ intel_screen_make_configs(__DRIscreen *dri_screen)
       MESA_FORMAT_B8G8R8A8_UNORM,
       MESA_FORMAT_B8G8R8X8_UNORM,
 
+      MESA_FORMAT_B8G8R8A8_SRGB,
+      MESA_FORMAT_B8G8R8X8_SRGB,
+
       /* The 32-bit RGBA format must not precede the 32-bit BGRA format.
        * Likewise for RGBX and BGRX.  Otherwise, the GLX client and the GLX
        * server may disagree on which format the GLXFBConfig represents,
-- 
2.13.5