[gtk] gl renderer: Keep op builder around

[Timm Bäder <baedert src gnome org>]

commit e13d242320f117fa6e0f12160128dc8a3ee60c80
Author: Timm Bäder <mail baedert org>
Date:   Wed Apr 24 17:55:14 2019 +0200

    gl renderer: Keep op builder around
    
    GL keeps the unoform state per-program, but not per-frame. So, we can't
    pretend that this works for us. Keep the RenderOpBuilder around for the
    entire lifetime of the renderer instead.

 gsk/gl/gskglrenderer.c  | 38 ++++++++++++++++++++------------------
 gsk/gl/gskglrenderops.c | 14 ++++++++++++++
 2 files changed, 34 insertions(+), 18 deletions(-)
---
diff --git a/gsk/gl/gskglrenderer.c b/gsk/gl/gskglrenderer.c
index 1ee037feb7..d91c107652 100644
--- a/gsk/gl/gskglrenderer.c
+++ b/gsk/gl/gskglrenderer.c
@@ -328,6 +328,7 @@ struct _GskGLRenderer
     };
   };
 
+  RenderOpBuilder op_builder;
   GArray *render_ops;
 
   GskGLGlyphCache glyph_cache;
@@ -2894,8 +2895,8 @@ gsk_gl_renderer_do_render (GskRenderer           *renderer,
                            int                    scale_factor)
 {
   GskGLRenderer *self = GSK_GL_RENDERER (renderer);
-  RenderOpBuilder render_op_builder;
   graphene_matrix_t modelview, projection;
+  gsize buffer_size;
 #ifdef G_ENABLE_DEBUG
   GskProfiler *profiler;
   gint64 gpu_time, cpu_time;
@@ -2927,13 +2928,9 @@ gsk_gl_renderer_do_render (GskRenderer           *renderer,
   gsk_gl_glyph_cache_begin_frame (&self->glyph_cache);
   gsk_gl_shadow_cache_begin_frame (&self->shadow_cache, self->gl_driver);
 
-  /* TODO: REALLY USE ONE BUILDER FOREVER! shader state is not per-frame... */
-  ops_init (&render_op_builder);
-  render_op_builder.renderer = self;
-  render_op_builder.current_projection = projection;
-  render_op_builder.current_viewport = *viewport;
-  render_op_builder.render_ops = self->render_ops;
-  ops_set_modelview (&render_op_builder, &modelview,
+  ops_set_projection (&self->op_builder, &projection);
+  ops_set_viewport (&self->op_builder, viewport);
+  ops_set_modelview (&self->op_builder, &modelview,
                      scale_factor == 1 ? GSK_TRANSFORM_CATEGORY_IDENTITY : GSK_TRANSFORM_CATEGORY_2D_AFFINE);
 
   /* Initial clip is self->render_region! */
@@ -2944,13 +2941,13 @@ gsk_gl_renderer_do_render (GskRenderer           *renderer,
 
       cairo_region_get_extents (self->render_region, &render_extents);
 
-      ops_transform_bounds_modelview (&render_op_builder,
+      ops_transform_bounds_modelview (&self->op_builder,
                                       &GRAPHENE_RECT_INIT (render_extents.x,
                                                            render_extents.y,
                                                            render_extents.width,
                                                            render_extents.height),
                                       &transformed_render_region);
-      ops_push_clip (&render_op_builder,
+      ops_push_clip (&self->op_builder,
                      &GSK_ROUNDED_RECT_INIT (transformed_render_region.origin.x,
                                              transformed_render_region.origin.y,
                                              transformed_render_region.size.width,
@@ -2958,7 +2955,7 @@ gsk_gl_renderer_do_render (GskRenderer           *renderer,
     }
   else
     {
-      ops_push_clip (&render_op_builder,
+      ops_push_clip (&self->op_builder,
                      &GSK_ROUNDED_RECT_INIT (viewport->origin.x,
                                              viewport->origin.y,
                                              viewport->size.width,
@@ -2966,15 +2963,16 @@ gsk_gl_renderer_do_render (GskRenderer           *renderer,
     }
 
   if (fbo_id != 0)
-    ops_set_render_target (&render_op_builder, fbo_id);
+    ops_set_render_target (&self->op_builder, fbo_id);
 
-  gsk_gl_renderer_add_render_ops (self, root, &render_op_builder);
+  gsk_gl_renderer_add_render_ops (self, root, &self->op_builder);
 
   /* We correctly reset the state everywhere */
-  g_assert_cmpint (render_op_builder.current_render_target, ==, fbo_id);
-  ops_pop_modelview (&render_op_builder);
-  ops_pop_clip (&render_op_builder);
-  ops_finish (&render_op_builder);
+  g_assert_cmpint (self->op_builder.current_render_target, ==, fbo_id);
+  ops_pop_modelview (&self->op_builder);
+  ops_pop_clip (&self->op_builder);
+  buffer_size = self->op_builder.buffer_size;
+  ops_finish (&self->op_builder);
 
   /*g_message ("Ops: %u", self->render_ops->len);*/
 
@@ -2996,7 +2994,7 @@ gsk_gl_renderer_do_render (GskRenderer           *renderer,
   glBlendFunc (GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
   glBlendEquation (GL_FUNC_ADD);
 
-  gsk_gl_renderer_render_ops (self, render_op_builder.buffer_size);
+  gsk_gl_renderer_render_ops (self, buffer_size);
 
 #ifdef G_ENABLE_DEBUG
   gsk_profiler_counter_inc (profiler, self->profile_counters.frames);
@@ -3143,6 +3141,10 @@ gsk_gl_renderer_init (GskGLRenderer *self)
 
   self->render_ops = g_array_new (FALSE, FALSE, sizeof (RenderOp));
 
+  ops_init (&self->op_builder);
+  self->op_builder.renderer = self;
+  self->op_builder.render_ops = self->render_ops;
+
 #ifdef G_ENABLE_DEBUG
   {
     GskProfiler *profiler = gsk_renderer_get_profiler (GSK_RENDERER (self));
diff --git a/gsk/gl/gskglrenderops.c b/gsk/gl/gskglrenderops.c
index f4c887fa59..34a7361bcf 100644
--- a/gsk/gl/gskglrenderops.c
+++ b/gsk/gl/gskglrenderops.c
@@ -12,9 +12,23 @@ ops_finish (RenderOpBuilder *builder)
 {
   if (builder->mv_stack)
     g_array_free (builder->mv_stack, TRUE);
+  builder->mv_stack = NULL;
 
   if (builder->clip_stack)
     g_array_free (builder->clip_stack, TRUE);
+  builder->clip_stack = NULL;
+
+  builder->buffer_size = 0;
+  builder->dx = 0;
+  builder->dy = 0;
+  builder->current_modelview = NULL;
+  builder->current_clip = NULL;
+  builder->current_render_target = 0;
+  builder->current_texture = 0;
+  builder->current_program = NULL;
+  builder->current_program_state = NULL;
+  graphene_matrix_init_identity (&builder->current_projection);
+  builder->current_viewport = GRAPHENE_RECT_INIT (0, 0, 0, 0);
 }
 
 static inline void