[Mesa-dev] [PATCH v2 2/4] mesa: extract need_xfb_remaining_prims_check

[Nicolai Hähnle]

From: Nicolai Hähnle <nicolai.haehnle at amd.com>

The same logic needs to be applied to glMultiDrawArrays.
---
 src/mesa/main/api_validate.c | 48 ++++++++++++++++++++++++++------------------
 1 file changed, 28 insertions(+), 20 deletions(-)

diff --git a/src/mesa/main/api_validate.c b/src/mesa/main/api_validate.c
index 8f83432..2e1829b 100644
--- a/src/mesa/main/api_validate.c
+++ b/src/mesa/main/api_validate.c
@@ -809,39 +809,24 @@ _mesa_validate_DrawRangeElements(struct gl_context *ctx, GLenum mode,
 
    if (end < start) {
       _mesa_error(ctx, GL_INVALID_VALUE, "glDrawRangeElements(end<start)");
       return GL_FALSE;
    }
 
    return validate_DrawElements_common(ctx, mode, count, type, indices,
                                        "glDrawRangeElements");
 }
 
+
 static bool
-validate_draw_arrays(struct gl_context *ctx, const char *func,
-                     GLenum mode, GLsizei count, GLsizei numInstances)
+need_xfb_remaining_prims_check(const struct gl_context *ctx)
 {
-   struct gl_transform_feedback_object *xfb_obj
-      = ctx->TransformFeedback.CurrentObject;
-   FLUSH_CURRENT(ctx, 0);
-
-   if (count < 0) {
-      _mesa_error(ctx, GL_INVALID_VALUE, "%s(count)", func);
-      return false;
-   }
-
-   if (!_mesa_valid_prim_mode(ctx, mode, func))
-      return false;
-
-   if (!check_valid_to_render(ctx, func))
-      return false;
-
    /* From the GLES3 specification, section 2.14.2 (Transform Feedback
     * Primitive Capture):
     *
     *   The error INVALID_OPERATION is generated by DrawArrays and
     *   DrawArraysInstanced if recording the vertices of a primitive to the
     *   buffer objects being used for transform feedback purposes would result
     *   in either exceeding the limits of any buffer object’s size, or in
     *   exceeding the end position offset + size − 1, as set by
     *   BindBufferRange.
     *
@@ -855,23 +840,46 @@ validate_draw_arrays(struct gl_context *ctx, const char *func,
     *    "(13) Does this extension change how transform feedback operates
     *     compared to unextended OpenGL ES 3.0 or 3.1?
     *
     *     RESOLVED: Yes. Because dynamic geometry amplification in a geometry
     *     shader can make it difficult if not impossible to predict the amount
     *     of geometry that may be generated in advance of executing the shader,
     *     the draw-time error for transform feedback buffer overflow conditions
     *     is removed and replaced with the GL behavior (primitives are not
     *     written and the corresponding counter is not updated)..."
     */
-   if (_mesa_is_gles3(ctx) && _mesa_is_xfb_active_and_unpaused(ctx) &&
-       !_mesa_has_OES_geometry_shader(ctx) &&
-       !_mesa_has_OES_tessellation_shader(ctx)) {
+   return _mesa_is_gles3(ctx) && _mesa_is_xfb_active_and_unpaused(ctx) &&
+          !_mesa_has_OES_geometry_shader(ctx) &&
+          !_mesa_has_OES_tessellation_shader(ctx);
+}
+
+
+static bool
+validate_draw_arrays(struct gl_context *ctx, const char *func,
+                     GLenum mode, GLsizei count, GLsizei numInstances)
+{
+   FLUSH_CURRENT(ctx, 0);
+
+   if (count < 0) {
+      _mesa_error(ctx, GL_INVALID_VALUE, "%s(count)", func);
+      return false;
+   }
+
+   if (!_mesa_valid_prim_mode(ctx, mode, func))
+      return false;
+
+   if (!check_valid_to_render(ctx, func))
+      return false;
+
+   if (need_xfb_remaining_prims_check(ctx)) {
+      struct gl_transform_feedback_object *xfb_obj
+         = ctx->TransformFeedback.CurrentObject;
       size_t prim_count = vbo_count_tessellated_primitives(mode, count, numInstances);
       if (xfb_obj->GlesRemainingPrims < prim_count) {
          _mesa_error(ctx, GL_INVALID_OPERATION,
                      "%s(exceeds transform feedback size)", func);
          return false;
       }
       xfb_obj->GlesRemainingPrims -= prim_count;
    }
 
    if (count == 0)
-- 
2.9.3