[gtk/wip/chergert/glproto] stub out simple transform nodes

[Christian Hergert <chergert src gnome org>]

commit 820c18a768317731091bdf31bcae743610a3eb5d
Author: Christian Hergert <chergert redhat com>
Date:   Wed Dec 30 11:33:09 2020 -0800

    stub out simple transform nodes

 gsk/next/gskglrenderjob.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 52 insertions(+), 1 deletion(-)
---
diff --git a/gsk/next/gskglrenderjob.c b/gsk/next/gskglrenderjob.c
index b9bbc9eab2..0b1b9f71b5 100644
--- a/gsk/next/gskglrenderjob.c
+++ b/gsk/next/gskglrenderjob.c
@@ -70,6 +70,9 @@ typedef struct _GskGLRenderModelview
   graphene_matrix_t matrix;
 } GskGLRenderModelview;
 
+static void gsk_gl_render_job_visit_node (GskGLRenderJob *job,
+                                          GskRenderNode  *node);
+
 static void
 init_projection_matrix (graphene_matrix_t     *projection,
                         const graphene_rect_t *viewport,
@@ -585,6 +588,51 @@ gsk_gl_render_job_visit_linear_gradient_node (GskGLRenderJob *job,
     }
 }
 
+static void
+gsk_gl_render_job_visit_transform_node (GskGLRenderJob *job,
+                                        GskRenderNode  *node)
+{
+  GskTransform *transform = gsk_transform_node_get_transform (node);
+  const GskTransformCategory category = gsk_transform_get_category (transform);
+  GskRenderNode *child = gsk_transform_node_get_child (node);
+
+  switch (category)
+    {
+    case GSK_TRANSFORM_CATEGORY_IDENTITY:
+      gsk_gl_render_job_visit_node (job, child);
+    break;
+
+    case GSK_TRANSFORM_CATEGORY_2D_TRANSLATE:
+      {
+        float dx, dy;
+
+        gsk_transform_to_translate (transform, &dx, &dy);
+        gsk_gl_render_job_offset (job, dx, dy);
+        gsk_gl_render_job_visit_node (job, child);
+        gsk_gl_render_job_offset (job, -dx, -dy);
+      }
+    break;
+
+    case GSK_TRANSFORM_CATEGORY_2D_AFFINE:
+      {
+        gsk_gl_render_job_push_modelview (job, transform);
+        gsk_gl_render_job_visit_node (job, child);
+        gsk_gl_render_job_pop_modelview (job);
+      }
+    break;
+
+    case GSK_TRANSFORM_CATEGORY_2D:
+    case GSK_TRANSFORM_CATEGORY_3D:
+    case GSK_TRANSFORM_CATEGORY_ANY:
+    case GSK_TRANSFORM_CATEGORY_UNKNOWN:
+      g_warning ("TODO: complex transform\n");
+    break;
+
+    default:
+      g_assert_not_reached ();
+    }
+}
+
 static void
 gsk_gl_render_job_visit_node (GskGLRenderJob *job,
                               GskRenderNode  *node)
@@ -637,6 +685,10 @@ gsk_gl_render_job_visit_node (GskGLRenderJob *job,
       gsk_gl_render_job_visit_linear_gradient_node (job, node);
     break;
 
+    case GSK_TRANSFORM_NODE:
+      gsk_gl_render_job_visit_transform_node (job, node);
+    break;
+
     case GSK_BLEND_NODE:
     case GSK_BLUR_NODE:
     case GSK_BORDER_NODE:
@@ -657,7 +709,6 @@ gsk_gl_render_job_visit_node (GskGLRenderJob *job,
     case GSK_SHADOW_NODE:
     case GSK_TEXTURE_NODE:
     case GSK_TEXT_NODE:
-    case GSK_TRANSFORM_NODE:
     break;
 
     case GSK_NOT_A_RENDER_NODE: