xlib,xcb: Force strict adherence to the Render specification when testing

Introduce cairo_xlib_device_debug_set_precision() to override the
automatic selection of rendering precision and force the Xorg/DDX to
strictly adhere to the precise rendering mode of the Render
specification. This allows us to test drivers without worrying, too
much, about minor discrepancies in antialiasing.

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

1 files changed, 20 insertions, 0 deletions

diff --git a/src/cairo-xcb-connection.c b/src/cairo-xcb-connection.c
index 0c244b1dc..56bf5aef6 100644
--- a/src/cairo-xcb-connection.c
+++ b/src/cairo-xcb-connection.c
@@ -889,3 +889,23 @@ cairo_xcb_device_debug_cap_xrender_version (cairo_device_t *device,
 	    connection->flags &= ~CAIRO_XCB_RENDER_HAS_GRADIENTS;
     }
 }
+
+
+void
+cairo_xcb_device_debug_set_precision (cairo_device_t *device,
+				      int precision)
+{
+    if (device->status)
+	    return;
+
+    ((cairo_xcb_connection_t *) device)->force_precision = precision;
+}
+
+int
+cairo_xcb_device_debug_get_precision (cairo_device_t *device)
+{
+    if (device->status)
+	    return -1;
+
+    return ((cairo_xcb_connection_t *) device)->force_precision;
+}