[Mesa-dev] [PATCH V3 1/4] mesa: implement GL_MAX_VERTEX_ATTRIB_STRIDE

[Timothy Arceri]

V2: moved test for the VertexAttrib*Pointer() functions
 to update_array(), and made constant available for drivers to set

Signed-off-by: Timothy Arceri <t_arceri at yahoo.com.au>
---

 Although 4.4 is a while away GL_MAX_VERTEX_ATTRIB_STRIDE is used in
 the ARB_direct_state_access spec so it seemed worth while adding this now.

 I've added MAX_VERTEX_ATTRIB_STRIDE to ARB_vertex_attrib_binding.xml
 as it didn't seem like it was worth putting it somewhere on its own
 as its really just a bug fix. Let me know if this should be moved.

 Finally I've assumed that 2048 is an ok value for i965.

 V3: adds values for r600g and radeonsi (I'm unsable to test either of these patches)

 Piglit tests:
 http://lists.freedesktop.org/archives/piglit/2014-August/012149.html

 src/mapi/glapi/gen/ARB_vertex_attrib_binding.xml |  1 +
 src/mesa/main/context.c                          |  3 +++
 src/mesa/main/get_hash_params.py                 |  3 +++
 src/mesa/main/mtypes.h                           |  3 +++
 src/mesa/main/varray.c                           | 22 ++++++++++++++++++++++
 5 files changed, 32 insertions(+)

diff --git a/src/mapi/glapi/gen/ARB_vertex_attrib_binding.xml b/src/mapi/glapi/gen/ARB_vertex_attrib_binding.xml
index 0ee6a3c..7e62688 100644
--- a/src/mapi/glapi/gen/ARB_vertex_attrib_binding.xml
+++ b/src/mapi/glapi/gen/ARB_vertex_attrib_binding.xml
@@ -53,6 +53,7 @@
     <enum name="VERTEX_BINDING_STRIDE" value="0x82D8"/>
     <enum name="MAX_VERTEX_ATTRIB_RELATIVE_OFFSET" value="0x82D9"/>
     <enum name="MAX_VERTEX_ATTRIB_BINDINGS" value="0x82DA"/>
+    <enum name="MAX_VERTEX_ATTRIB_STRIDE" value="0x82E5"/>
 
 </category>
 </OpenGLAPI>
diff --git a/src/mesa/main/context.c b/src/mesa/main/context.c
index 2320842..fbdbd68 100644
--- a/src/mesa/main/context.c
+++ b/src/mesa/main/context.c
@@ -670,6 +670,9 @@ _mesa_init_constants(struct gl_constants *consts, gl_api api)
                           ? GL_CONTEXT_CORE_PROFILE_BIT
                           : GL_CONTEXT_COMPATIBILITY_PROFILE_BIT;
 
+   /* GL 4.4 */
+   consts->MaxVertexAttribStride = 2048;
+
    /** GL_EXT_gpu_shader4 */
    consts->MinProgramTexelOffset = -8;
    consts->MaxProgramTexelOffset = 7;
diff --git a/src/mesa/main/get_hash_params.py b/src/mesa/main/get_hash_params.py
index ff85820..aace8a5 100644
--- a/src/mesa/main/get_hash_params.py
+++ b/src/mesa/main/get_hash_params.py
@@ -712,6 +712,9 @@ descriptor=[
   [ "MAX_GEOMETRY_INPUT_COMPONENTS", "CONTEXT_INT(Const.Program[MESA_SHADER_GEOMETRY].MaxInputComponents), extra_version_32" ],
   [ "MAX_GEOMETRY_OUTPUT_COMPONENTS", "CONTEXT_INT(Const.Program[MESA_SHADER_GEOMETRY].MaxOutputComponents), extra_version_32" ],
 
+# GL 4.4
+  [ "MAX_VERTEX_ATTRIB_STRIDE", "CONTEXT_ENUM(Const.MaxVertexAttribStride), NO_EXTRA" ],
+
 # GL_ARB_robustness
   [ "RESET_NOTIFICATION_STRATEGY_ARB", "CONTEXT_ENUM(Const.ResetStrategy), NO_EXTRA" ],
 
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index cb2a4df..adb6788 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -3414,6 +3414,9 @@ struct gl_constants
    /** OpenGL version 3.2 */
    GLbitfield ProfileMask;   /**< Mask of CONTEXT_x_PROFILE_BIT */
 
+   /** OpenGL version 4.4 */
+   GLuint MaxVertexAttribStride;
+
    /** GL_EXT_transform_feedback */
    GLuint MaxTransformFeedbackBuffers;
    GLuint MaxTransformFeedbackSeparateComponents;
diff --git a/src/mesa/main/varray.c b/src/mesa/main/varray.c
index 5d3cc2a..7d169f9 100644
--- a/src/mesa/main/varray.c
+++ b/src/mesa/main/varray.c
@@ -424,6 +424,13 @@ update_array(struct gl_context *ctx,
       return;
    }
 
+   if (ctx->API == API_OPENGL_CORE && ctx->Version >= 44 &&
+       stride > ctx->Const.MaxVertexAttribStride) {
+      _mesa_error(ctx, GL_INVALID_VALUE, "%s(stride=%d > "
+                  "GL_MAX_VERTEX_ATTRIB_STRIDE)", func, stride);
+      return;
+   }
+
    /* Page 29 (page 44 of the PDF) of the OpenGL 3.3 spec says:
     *
     *     "An INVALID_OPERATION error is generated under any of the following
@@ -1437,6 +1444,13 @@ _mesa_BindVertexBuffer(GLuint bindingIndex, GLuint buffer, GLintptr offset,
       return;
    }
 
+   if (ctx->API == API_OPENGL_CORE && ctx->Version >= 44 &&
+       stride > ctx->Const.MaxVertexAttribStride) {
+      _mesa_error(ctx, GL_INVALID_VALUE, "glBindVertexBuffer(stride=%d > "
+                  "GL_MAX_VERTEX_ATTRIB_STRIDE)", stride);
+      return;
+   }
+
    if (buffer == vao->VertexBinding[VERT_ATTRIB_GENERIC(bindingIndex)].BufferObj->Name) {
       vbo = vao->VertexBinding[VERT_ATTRIB_GENERIC(bindingIndex)].BufferObj;
    } else if (buffer != 0) {
@@ -1565,6 +1579,14 @@ _mesa_BindVertexBuffers(GLuint first, GLsizei count, const GLuint *buffers,
          continue;
       }
 
+      if (ctx->API == API_OPENGL_CORE && ctx->Version >= 44 &&
+          strides[i] > ctx->Const.MaxVertexAttribStride) {
+         _mesa_error(ctx, GL_INVALID_VALUE,
+                     "glBindVertexBuffers(strides[%u]=%d > "
+                     "GL_MAX_VERTEX_ATTRIB_STRIDE)", i, strides[i]);
+         continue;
+      }
+
       if (buffers[i]) {
          struct gl_vertex_buffer_binding *binding =
             &vao->VertexBinding[VERT_ATTRIB_GENERIC(first + i)];
-- 
1.9.3