ngl: Determine intermediate formats

Look at the framebuffer and the rendernode to
determine what format to use for intermediate
textures.

Our preference here is to use fp16, if we have it
and it makes sense for the framebuffer we're given.

diff --git a/gsk/ngl/gsknglrenderjob.c b/gsk/ngl/gsknglrenderjob.c
index d285eb24b04732f502a2323023bc1065337c8b1f..e3436e10f486bccec877ca34d40bc4b21e687a83 100644 (file)
--- a/gsk/ngl/gsknglrenderjob.c
+++ b/gsk/ngl/gsknglrenderjob.c
@@ -162,6 +162,11 @@ struct _GskNglRenderJob
 
   /* If we should be rendering red zones over fallback nodes */
   guint debug_fallback : 1;
+
+  /* Format we want to use for intermediate textures, determined by
+   * looking at the format of the framebuffer we are rendering on.
+   */
+  int target_format;
 };
 
 typedef struct _GskNglRenderOffscreen
@@ -198,6 +203,16 @@ static gboolean gsk_ngl_render_job_visit_node_with_offscreen (GskNglRenderJob
                                                               const GskRenderNode  *node,
                                                               GskNglRenderOffscreen *offscreen);
 
+static inline int
+get_target_format (GskNglRenderJob     *job,
+                   const GskRenderNode *node)
+{
+  if (gsk_render_node_prefers_high_depth (node))
+    return job->target_format;
+
+  return GL_RGBA8;
+}
+
 static inline void
 init_full_texture_region (GskNglRenderOffscreen *offscreen)
 {
@@ -1258,7 +1273,7 @@ blur_offscreen (GskNglRenderJob       *job,
   if (!gsk_ngl_driver_create_render_target (job->driver,
                                              MAX (texture_to_blur_width, 1),
                                              MAX (texture_to_blur_height, 1),
-                                             GL_RGBA8,
+                                             job->target_format,
                                              GL_NEAREST, GL_NEAREST,
                                              &pass1))
     return 0;
@@ -1269,7 +1284,7 @@ blur_offscreen (GskNglRenderJob       *job,
   if (!gsk_ngl_driver_create_render_target (job->driver,
                                              texture_to_blur_width,
                                              texture_to_blur_height,
-                                             GL_RGBA8,
+                                             job->target_format,
                                              GL_NEAREST, GL_NEAREST,
                                              &pass2))
     return gsk_ngl_driver_release_render_target (job->driver, pass1, FALSE);
@@ -2181,7 +2196,7 @@ gsk_ngl_render_job_visit_blurred_inset_shadow_node (GskNglRenderJob     *job,
 
       if (!gsk_ngl_driver_create_render_target (job->driver,
                                                  texture_width, texture_height,
-                                                 GL_RGBA8,
+                                                 get_target_format (job, node),
                                                  GL_NEAREST, GL_NEAREST,
                                                  &render_target))
         g_assert_not_reached ();
@@ -2452,7 +2467,7 @@ gsk_ngl_render_job_visit_blurred_outset_shadow_node (GskNglRenderJob     *job,
 
       gsk_ngl_driver_create_render_target (job->driver,
                                            texture_width, texture_height,
-                                           GL_RGBA8,
+                                           get_target_format (job, node),
                                            GL_NEAREST, GL_NEAREST,
                                            &render_target);
 
@@ -3860,7 +3875,7 @@ gsk_ngl_render_job_visit_node_with_offscreen (GskNglRenderJob       *job,
 
   if (!gsk_ngl_driver_create_render_target (job->driver,
                                              scaled_width, scaled_height,
-                                             GL_RGBA8,
+                                             get_target_format (job, node),
                                              filter, filter,
                                              &render_target))
     g_assert_not_reached ();
@@ -3959,7 +3974,7 @@ gsk_ngl_render_job_render_flipped (GskNglRenderJob *job,
   if (!gsk_ngl_command_queue_create_render_target (job->command_queue,
                                                   MAX (1, job->viewport.size.width),
                                                   MAX (1, job->viewport.size.height),
-                                                  GL_RGBA8,
+                                                  job->target_format,
                                                   GL_NEAREST, GL_NEAREST,
                                                   &framebuffer_id, &texture_id))
     return;
@@ -4050,6 +4065,22 @@ gsk_ngl_render_job_set_debug_fallback (GskNglRenderJob *job,
   job->debug_fallback = !!debug_fallback;
 }
 
+static int
+get_framebuffer_format (guint framebuffer)
+{
+  int size;
+
+  glBindFramebuffer (GL_FRAMEBUFFER, framebuffer);
+  glGetFramebufferAttachmentParameteriv (GL_FRAMEBUFFER,  GL_COLOR_ATTACHMENT0, GL_FRAMEBUFFER_ATTACHMENT_RED_SIZE, &size);
+
+  if (size >= 32)
+    return GL_RGBA32F;
+  else if (size >= 16)
+    return GL_RGBA16F;
+  else
+    return GL_RGBA8;
+}
+
 GskNglRenderJob *
 gsk_ngl_render_job_new (GskNglDriver          *driver,
                         const graphene_rect_t *viewport,
@@ -4076,6 +4107,7 @@ gsk_ngl_render_job_new (GskNglDriver          *driver,
   job->scale_x = scale_factor;
   job->scale_y = scale_factor;
   job->viewport = *viewport;
+  job->target_format = get_framebuffer_format (framebuffer);
 
   gsk_ngl_render_job_set_alpha (job, 1.0f);
   gsk_ngl_render_job_set_projection_from_rect (job, viewport, NULL);