Resolve "Daybound & Nightbound"

forge-gui-mobile-dev/shaders/outline.frag

@@ -0,0 +1,40 @@
+#ifdef GL_ES
+precision mediump float;
+precision mediump int;
+#endif
+
+uniform sampler2D u_texture;
+uniform vec2 u_viewportInverse;
+uniform vec3 u_color;
+uniform float u_offset;
+uniform float u_step;
+
+varying vec4 v_color;
+varying vec2 v_texCoord;
+
+#define ALPHA_VALUE_BORDER 0.5
+
+void main() {
+   vec2 T = v_texCoord.xy;
+
+   float alpha = 0.0;
+   bool allin = true;
+   for( float ix = -u_offset; ix < u_offset; ix += u_step )
+   {
+      for( float iy = -u_offset; iy < u_offset; iy += u_step )
+       {
+          float newAlpha = texture2D(u_texture, T + vec2(ix, iy) * u_viewportInverse).a;
+          allin = allin && newAlpha > ALPHA_VALUE_BORDER;
+          if (newAlpha > ALPHA_VALUE_BORDER && newAlpha >= alpha)
+          {
+             alpha = newAlpha;
+          }
+      }
+   }
+   if (allin)
+   {
+      alpha = 0.0;
+   }
+
+   gl_FragColor = vec4(u_color,alpha);
+}