[Mesa-dev] [PATCH 49/65] mesa/formatquery: Added simultaneous texture and depth/stencil queries

[Eduardo Lima Mitev]

From: Antia Puentes <apuentes at igalia.com>

>From the ARB_internalformat_query2 specification:

   "- SIMULTANEOUS_TEXTURE_AND_DEPTH_TEST: The support for using the resource
      both as a source for texture sampling while it is bound as a buffer for
      depth test is written to <params>. For example, a depth (or stencil)
      texture could be bound simultaneously for texturing while it is bound as
      a depth (and/or stencil) buffer without causing a feedback loop, provided
      that depth writes are disabled.

    - SIMULTANEOUS_TEXTURE_AND_STENCIL_TEST: The support for using the resource
      both as a source for texture sampling while it is bound as a buffer for
      stencil test is written to <params>. For example, a depth (or stencil)
      texture could be bound simultaneously for texturing while it is bound as
      a depth (and/or stencil) buffer without causing a feedback loop,
      provided that stencil writes are disabled.

    - SIMULTANEOUS_TEXTURE_AND_DEPTH_WRITE: The support for using the resource
      both as a source for texture sampling while performing depth writes to
      the resources is written to <params>.  For example, a depth-stencil
      texture could be bound simultaneously for stencil texturing while it
      is bound as a depth buffer. Feedback loops cannot occur because sampling
      a stencil texture only returns the stencil portion, and thus writes to
      the depth buffer do not modify the stencil portions.

    - SIMULTANEOUS_TEXTURE_AND_STENCIL_WRITE: The support for using the resource
      both as a source for texture sampling while performing stencil writes to
      the resources is written to <params>.  For example, a depth-stencil
      texture could be bound simultaneously for depth-texturing while it is
      bound as a stencil buffer. Feedback loops cannot occur because sampling
      a depth texture only returns the depth portion, and thus writes to
      the stencil buffer could not modify the depth portions.

For all of them,
    "Possible values returned are FULL_SUPPORT, CAVEAT_SUPPORT, or NONE.
     If the resource or operation is not supported, NONE is returned."
---
 src/mesa/main/formatquery.c | 29 +++++++++++++++++++----------
 1 file changed, 19 insertions(+), 10 deletions(-)

diff --git a/src/mesa/main/formatquery.c b/src/mesa/main/formatquery.c
index f25bcec..a62a8ac 100644
--- a/src/mesa/main/formatquery.c
+++ b/src/mesa/main/formatquery.c
@@ -606,6 +606,10 @@ _mesa_query_internal_format_default(struct gl_context *ctx, GLenum target,
    case GL_SHADER_IMAGE_LOAD:
    case GL_SHADER_IMAGE_STORE:
    case GL_SHADER_IMAGE_ATOMIC:
+   case GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_TEST:
+   case GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_TEST:
+   case GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_WRITE:
+   case GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_WRITE:
       params[0] = GL_FULL_SUPPORT;
       break;
 
@@ -1286,19 +1290,24 @@ _mesa_GetInternalformativ(GLenum target, GLenum internalformat, GLenum pname,
    }
 
    case GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_TEST:
-      /* @TODO */
-      break;
-
    case GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_TEST:
-      /* @TODO */
-      break;
-
    case GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_WRITE:
-      /* @TODO */
-      break;
-
    case GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_WRITE:
-      /* @TODO */
+      if (target == GL_RENDERBUFFER)
+         goto end;
+
+      if (!_mesa_is_depthstencil_format(internalformat)) {
+         if (((pname == GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_TEST ||
+               pname == GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_WRITE) &&
+              !_mesa_is_depth_format(internalformat)) ||
+             ((pname == GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_TEST ||
+               pname == GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_WRITE) &&
+              !_mesa_is_stencil_format(internalformat)))
+            goto end;
+      }
+
+      ctx->Driver.QueryInternalFormat(ctx, target, internalformat, pname,
+                                      buffer);
       break;
 
    case GL_TEXTURE_COMPRESSED:
-- 
2.5.3