Merge pull request #95536 from jsjtxietian/rename-alpha-scissor

Fix undefined `alpha_scissor` in standard shader

drivers/gles3/shaders/scene.glsl

@@ -1871,7 +1871,7 @@ void main() {
 	alpha = min(alpha, clamp(length(ambient_light), 0.0, 1.0));
 
 #if defined(ALPHA_SCISSOR_USED)
-	if (alpha < alpha_scissor) {
+	if (alpha < alpha_scissor_threshold) {
 		discard;
 	}
 #endif // !ALPHA_SCISSOR_USED

servers/rendering/renderer_rd/shaders/forward_clustered/scene_forward_clustered.glsl

@@ -2242,7 +2242,7 @@ void fragment_shader(in SceneData scene_data) {
 	alpha = min(alpha, clamp(length(ambient_light), 0.0, 1.0));
 
 #if defined(ALPHA_SCISSOR_USED)
-	if (alpha < alpha_scissor) {
+	if (alpha < alpha_scissor_threshold) {
 		discard;
 	}
 #endif // ALPHA_SCISSOR_USED

servers/rendering/renderer_rd/shaders/forward_mobile/scene_forward_mobile.glsl

@@ -1765,7 +1765,7 @@ void main() {
 	alpha = min(alpha, clamp(length(ambient_light), 0.0, 1.0));
 
 #if defined(ALPHA_SCISSOR_USED)
-	if (alpha < alpha_scissor) {
+	if (alpha < alpha_scissor_threshold) {
 		discard;
 	}
 #endif // !ALPHA_SCISSOR_USED