xlib: Replace obsolete disable-xrender with shiny new device debug interface

As prototyped with xcb.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 50 insertions, 7 deletions

diff --git a/src/cairo-xlib-display.c b/src/cairo-xlib-display.c
index fd7253cc2..65cd3fbea 100644
--- a/src/cairo-xlib-display.c
+++ b/src/cairo-xlib-display.c
@@ -146,6 +146,17 @@ static const cairo_device_backend_t _cairo_xlib_device_backend = {
     _cairo_xlib_display_destroy,
 };
 
+
+static void _cairo_xlib_display_select_compositor (cairo_xlib_display_t *display)
+{
+    if (display->render_major > 0 || display->render_minor >= 4)
+	display->compositor = _cairo_xlib_traps_compositor_get ();
+    else if (display->render_major > 0 || display->render_minor >= 0)
+	display->compositor = _cairo_xlib_mask_compositor_get ();
+    else
+	display->compositor = _cairo_xlib_core_compositor_get ();
+}
+
 /**
  * cairo_xlib_device_create:
  * @dpy: the display to create the device for
@@ -221,6 +232,8 @@ _cairo_xlib_device_create (Display *dpy)
 	}
     }
 
+    _cairo_xlib_display_select_compositor (display);
+
     codes = XAddExtension (dpy);
     if (unlikely (codes == NULL)) {
 	device = _cairo_device_create_in_error (CAIRO_STATUS_NO_MEMORY);
@@ -331,13 +344,6 @@ _cairo_xlib_device_create (Display *dpy)
 	display->buggy_pad_reflect = TRUE;
     }
 
-    if (display->render_major > 0 || display->render_minor >= 4)
-	display->compositor = _cairo_xlib_traps_compositor_get ();
-    else if (display->render_major > 0 || display->render_minor >= 0)
-	display->compositor = _cairo_xlib_mask_compositor_get ();
-    else
-	display->compositor = _cairo_xlib_core_compositor_get ();
-
     display->next = _cairo_xlib_display_list;
     _cairo_xlib_display_list = display;
 
@@ -552,6 +558,43 @@ _cairo_xlib_display_has_gradients (cairo_device_t *device)
     return ! ((cairo_xlib_display_t *) device)->buggy_gradients;
 }
 
+/**
+ * cairo_xlib_device_debug_cap_xrender_version:
+ * @device: a #cairo_device_t for the XCB backend
+ * @major_version: major version to restrict to
+ * @minor_version: minor version to restrict to
+ *
+ * Restricts all future XCB surfaces for this devices to the specified version
+ * of the RENDER extension. This function exists solely for debugging purpose.
+ * It let's you find out how cairo would behave with an older version of
+ * the RENDER extension.
+ *
+ * Use the special values -1 and -1 for disabling the RENDER extension.
+ **/
+void
+cairo_xlib_device_debug_cap_xrender_version (cairo_device_t *device,
+					     int major_version,
+					     int minor_version)
+{
+    cairo_xlib_display_t *display = (cairo_xlib_display_t *) device;
+
+    if (device == NULL || device->status)
+	return;
+
+    if (device->backend->type != CAIRO_DEVICE_TYPE_XLIB)
+	return;
+
+    if (major_version < display->render_major ||
+	(major_version == display->render_major &&
+	 minor_version < display->render_minor))
+    {
+	display->render_major = major_version;
+	display->render_minor = minor_version;
+    }
+
+    _cairo_xlib_display_select_compositor (display);
+}
+
 void
 cairo_xlib_device_debug_set_precision (cairo_device_t *device,
 				       int precision)