glyphy: Declare that we are using dFdx

GLES2 does not have these by default :(
2023-07-18 23:45:06 -04:00
parent 73a82faad3
commit cc250beadc
1 changed files with 2 additions and 0 deletions
--- a/gsk/gl/resources/preamble.glsl
+++ b/gsk/gl/resources/preamble.glsl
@@ -1,3 +1,5 @@
+#extension GL_OES_standard_derivatives : enable
+
 #ifndef GSK_LEGACY
 precision highp float;
 #endif