mesa: move glMultiDrawArrays to vbo and fix error handling

When any count[i] is negative, we must skip all draws.

Moving to vbo makes the subsequent change easier.

v2:
- provide the function in all contexts, including GLES
- adjust validation accordingly to include the xfb check
v3:
- fix mix-up of pre- and post-xfb prim count (Nils Wallménius)

Cc: [email protected]
Reviewed-by: Timothy Arceri <[email protected]>
Reviewed-by: Marek Olšák <[email protected]>

2 files changed, 68 insertions, 0 deletions

diff --git a/src/mesa/vbo/vbo_exec_array.c b/src/mesa/vbo/vbo_exec_array.c
index 30c52d5fa4f..6858eb30b73 100644
--- a/src/mesa/vbo/vbo_exec_array.c
+++ b/src/mesa/vbo/vbo_exec_array.c
@@ -637,6 +637,38 @@ vbo_exec_DrawArraysInstancedBaseInstance(GLenum mode, GLint first,
 }
 
 
+/**
+ * Called from glMultiDrawArrays when in immediate mode.
+ */
+static void GLAPIENTRY
+vbo_exec_MultiDrawArrays(GLenum mode, const GLint *first,
+                         const GLsizei *count, GLsizei primcount)
+{
+   GET_CURRENT_CONTEXT(ctx);
+   GLint i;
+
+   if (MESA_VERBOSE & VERBOSE_DRAW)
+      _mesa_debug(ctx,
+                  "glMultiDrawArrays(%s, %p, %p, %d)\n",
+                  _mesa_enum_to_string(mode), first, count, primcount);
+
+   if (!_mesa_validate_MultiDrawArrays(ctx, mode, count, primcount))
+      return;
+
+   for (i = 0; i < primcount; i++) {
+      if (count[i] > 0) {
+         if (0)
+            check_draw_arrays_data(ctx, first[i], count[i]);
+
+         vbo_draw_arrays(ctx, mode, first[i], count[i], 1, 0);
+
+         if (0)
+            print_draw_arrays(ctx, mode, first[i], count[i]);
+      }
+   }
+}
+
+
 
 /**
  * Map GL_ELEMENT_ARRAY_BUFFER and print contents.
@@ -1641,6 +1673,7 @@ vbo_initialize_exec_dispatch(const struct gl_context *ctx,
       SET_DrawRangeElements(exec, vbo_exec_DrawRangeElements);
    }
 
+   SET_MultiDrawArrays(exec, vbo_exec_MultiDrawArrays);
    SET_MultiDrawElementsEXT(exec, vbo_exec_MultiDrawElements);
 
    if (ctx->API == API_OPENGL_COMPAT) {
diff --git a/src/mesa/vbo/vbo_save_api.c b/src/mesa/vbo/vbo_save_api.c
index f8dab0cdaa7..ad54c3b38b3 100644
--- a/src/mesa/vbo/vbo_save_api.c
+++ b/src/mesa/vbo/vbo_save_api.c
@@ -1176,6 +1176,40 @@ _save_OBE_DrawArrays(GLenum mode, GLint start, GLsizei count)
 }
 
 
+static void GLAPIENTRY
+_save_OBE_MultiDrawArrays(GLenum mode, const GLint *first,
+                          const GLsizei *count, GLsizei primcount)
+{
+   GET_CURRENT_CONTEXT(ctx);
+   GLint i;
+
+   if (!_mesa_is_valid_prim_mode(ctx, mode)) {
+      _mesa_compile_error(ctx, GL_INVALID_ENUM, "glMultiDrawArrays(mode)");
+      return;
+   }
+
+   if (primcount < 0) {
+      _mesa_compile_error(ctx, GL_INVALID_VALUE,
+                          "glMultiDrawArrays(primcount<0)");
+      return;
+   }
+
+   for (i = 0; i < primcount; i++) {
+      if (count[i] < 0) {
+         _mesa_compile_error(ctx, GL_INVALID_VALUE,
+                             "glMultiDrawArrays(count[i]<0)");
+         return;
+      }
+   }
+
+   for (i = 0; i < primcount; i++) {
+      if (count[i] > 0) {
+         _save_OBE_DrawArrays(mode, first[i], count[i]);
+      }
+   }
+}
+
+
 /* Could do better by copying the arrays and element list intact and
  * then emitting an indexed prim at runtime.
  */
@@ -1484,6 +1518,7 @@ vbo_initialize_save_dispatch(const struct gl_context *ctx,
                              struct _glapi_table *exec)
 {
    SET_DrawArrays(exec, _save_OBE_DrawArrays);
+   SET_MultiDrawArrays(exec, _save_OBE_MultiDrawArrays);
    SET_DrawElements(exec, _save_OBE_DrawElements);
    SET_DrawElementsBaseVertex(exec, _save_OBE_DrawElementsBaseVertex);
    SET_DrawRangeElements(exec, _save_OBE_DrawRangeElements);