mesa/vbo: Move _vbo_draw_indirect -> _mesa_draw_indirect

Reviewed-by: Brian Paul <[email protected]>
Signed-off-by: Mathias Fröhlich <[email protected]>

1 files changed, 74 insertions, 0 deletions

diff --git a/src/mesa/main/draw.c b/src/mesa/main/draw.c
index 7729a860d02..85a9eedbc32 100644
--- a/src/mesa/main/draw.c
+++ b/src/mesa/main/draw.c
@@ -29,6 +29,7 @@
 #include <stdio.h>
 #include "arrayobj.h"
 #include "glheader.h"
+#include "c99_alloca.h"
 #include "context.h"
 #include "state.h"
 #include "draw.h"
@@ -2143,3 +2144,76 @@ _mesa_DrawTransformFeedback(GLenum mode, GLuint name)
 {
    _mesa_exec_DrawTransformFeedback(mode, name);
 }
+
+
+/*
+ * Helper function for _mesa_draw_indirect below that additionally takes a zero
+ * initialized array of _mesa_prim scratch space memory as the last argument.
+ */
+static void
+draw_indirect(struct gl_context *ctx, GLuint mode,
+              struct gl_buffer_object *indirect_data,
+              GLsizeiptr indirect_offset, unsigned draw_count,
+              unsigned stride,
+              struct gl_buffer_object *indirect_draw_count_buffer,
+              GLsizeiptr indirect_draw_count_offset,
+              const struct _mesa_index_buffer *ib,
+              struct _mesa_prim *prim)
+{
+   prim[0].begin = 1;
+   prim[draw_count - 1].end = 1;
+   for (unsigned i = 0; i < draw_count; ++i, indirect_offset += stride) {
+      prim[i].mode = mode;
+      prim[i].indexed = !!ib;
+      prim[i].indirect_offset = indirect_offset;
+      prim[i].is_indirect = 1;
+      prim[i].draw_id = i;
+   }
+
+   /* This should always be true at this time */
+   assert(indirect_data == ctx->DrawIndirectBuffer);
+
+   ctx->Driver.Draw(ctx, prim, draw_count, ib, false, 0u, ~0u,
+                    NULL, 0, indirect_data);
+}
+
+
+/*
+ * Function to be put into dd_function_table::DrawIndirect as fallback.
+ * Calls into dd_function_table::Draw past adapting call arguments.
+ * See dd_function_table::DrawIndirect for call argument documentation.
+ */
+void
+_mesa_draw_indirect(struct gl_context *ctx, GLuint mode,
+                    struct gl_buffer_object *indirect_data,
+                    GLsizeiptr indirect_offset, unsigned draw_count,
+                    unsigned stride,
+                    struct gl_buffer_object *indirect_draw_count_buffer,
+                    GLsizeiptr indirect_draw_count_offset,
+                    const struct _mesa_index_buffer *ib)
+{
+   /* Use alloca for the prim space if we are somehow in bounds. */
+   if (draw_count*sizeof(struct _mesa_prim) < 1024) {
+      struct _mesa_prim *space = alloca(draw_count*sizeof(struct _mesa_prim));
+      memset(space, 0, draw_count*sizeof(struct _mesa_prim));
+
+      draw_indirect(ctx, mode, indirect_data, indirect_offset, draw_count,
+                    stride, indirect_draw_count_buffer,
+                    indirect_draw_count_offset, ib, space);
+   } else {
+      struct _mesa_prim *space = calloc(draw_count, sizeof(struct _mesa_prim));
+      if (space == NULL) {
+         _mesa_error(ctx, GL_OUT_OF_MEMORY, "gl%sDraw%sIndirect%s",
+                     (draw_count > 1) ? "Multi" : "",
+                     ib ? "Elements" : "Arrays",
+                     indirect_data ? "CountARB" : "");
+         return;
+      }
+
+      draw_indirect(ctx, mode, indirect_data, indirect_offset, draw_count,
+                    stride, indirect_draw_count_buffer,
+                    indirect_draw_count_offset, ib, space);
+
+      free(space);
+   }
+}