[gtk+] gsk: Add check on GL_MAX_TEXTURE_SIZE

[Emmanuele Bassi <ebassi src gnome org>]

commit e161f9eba332a85027f165e4a7cd7c641db8aaa4
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Wed Oct 26 15:47:29 2016 +0100

    gsk: Add check on GL_MAX_TEXTURE_SIZE
    
    We should check (once) what's the maximum GL texture size and then use
    that size to check when we create any GL texture, to avoid errors.

 gsk/gskgldriver.c        |   35 +++++++++++++++++++++++++++++++++++
 gsk/gskgldriverprivate.h |    2 ++
 2 files changed, 37 insertions(+), 0 deletions(-)
---
diff --git a/gsk/gskgldriver.c b/gsk/gskgldriver.c
index 2f045cf..a0bd8e3 100644
--- a/gsk/gskgldriver.c
+++ b/gsk/gskgldriver.c
@@ -48,6 +48,8 @@ struct _GskGLDriver
   Vao *bound_vao;
   Fbo *bound_fbo;
 
+  int max_texture_size;
+
   gboolean in_frame : 1;
 };
 
@@ -184,6 +186,8 @@ gsk_gl_driver_init (GskGLDriver *self)
 {
   self->textures = g_hash_table_new_full (NULL, NULL, NULL, texture_free);
   self->vaos = g_hash_table_new_full (NULL, NULL, NULL, vao_free);
+
+  self->max_texture_size = -1;
 }
 
 GskGLDriver *
@@ -204,6 +208,12 @@ gsk_gl_driver_begin_frame (GskGLDriver *driver)
 
   driver->in_frame = TRUE;
 
+  if (driver->max_texture_size < 0)
+    {
+      glGetIntegerv (GL_MAX_TEXTURE_SIZE, (GLint *) &driver->max_texture_size);
+      GSK_NOTE (OPENGL, g_print ("GL max texture size: %d\n", driver->max_texture_size));
+    }
+
   glGetIntegerv (GL_FRAMEBUFFER_BINDING, (GLint *) &(driver->default_fbo.fbo_id));
   driver->bound_fbo = &driver->default_fbo;
 
@@ -297,6 +307,20 @@ gsk_gl_driver_collect_vaos (GskGLDriver *driver)
   return old_size - g_hash_table_size (driver->vaos);
 }
 
+int
+gsk_gl_driver_get_max_texture_size (GskGLDriver *driver)
+{
+  if (driver->max_texture_size < 0)
+    {
+      if (gdk_gl_context_get_use_es (driver->gl_context))
+        return 2048;
+
+      return 1024;
+    }
+
+  return driver->max_texture_size;
+}
+
 static Texture *
 gsk_gl_driver_get_texture (GskGLDriver *driver,
                            int          texture_id)
@@ -363,6 +387,17 @@ gsk_gl_driver_create_texture (GskGLDriver *driver,
 
   g_return_val_if_fail (GSK_IS_GL_DRIVER (driver), -1);
 
+  if (width >= driver->max_texture_size ||
+      height >= driver->max_texture_size)
+    {
+      g_critical ("Texture %d x %d is bigger than supported texture limit of %d; clipping...",
+                  width, height,
+                  driver->max_texture_size);
+
+      width = MIN (width, driver->max_texture_size);
+      height = MIN (height, driver->max_texture_size);
+    }
+
   t = find_texture_by_size (driver->textures, width, height);
   if (t != NULL && !t->in_use)
     {
diff --git a/gsk/gskgldriverprivate.h b/gsk/gskgldriverprivate.h
index f4836f5..6a41174 100644
--- a/gsk/gskgldriverprivate.h
+++ b/gsk/gskgldriverprivate.h
@@ -18,6 +18,8 @@ typedef struct {
 
 GskGLDriver *   gsk_gl_driver_new                       (GdkGLContext    *context);
 
+int             gsk_gl_driver_get_max_texture_size      (GskGLDriver     *driver);
+
 void            gsk_gl_driver_begin_frame               (GskGLDriver     *driver);
 void            gsk_gl_driver_end_frame                 (GskGLDriver     *driver);