Added VFEZ

VFEZ/Shaders/Effects/vfez_alpha_mask.gdshaderinc

@@ -0,0 +1,23 @@
+#ifndef VFEZ_UTILS
+	#include "vfez_utils.gdshaderinc"
+	#define VFEZ_UTILS
+#endif
+
+group_uniforms alpha_mask;
+uniform sampler2D alpha_mask_texture: source_color;
+uniform vec2 alpha_mask_scale = vec2(1.);
+uniform vec2 alpha_mask_offset = vec2(0.);
+uniform float alpha_mask_power: hint_range(0.001, 10.) = 1;
+group_uniforms;
+
+float alpha_mask(
+	float alpha,
+	vec2 uv,
+	bool fract_uv)
+{
+	vec2 alpha_mask_uv = transform_uv(uv, alpha_mask_scale, alpha_mask_offset, fract_uv);
+	vec4 alpha_mask_sample = texture(alpha_mask_texture, alpha_mask_uv);
+	float mask = pow(min(alpha_mask_sample.r, alpha_mask_sample.a), alpha_mask_power);
+	alpha *= mask;
+	return alpha;
+}