Move towards pixel upscaling filter

shader/texture/antia.frag

@@ -0,0 +1,21 @@
+#version 450 core
+in vec2 vTexPos;
+out vec4 fColor;
+layout (location = 0) uniform vec2 screensize;
+layout(binding = 0) uniform sampler2D screenTexture;
+float xoff = 2 / screensize.x;
+float yoff = 2 / screensize.y;
+vec3 f (float x, float y)
+{ return texture(screenTexture, vTexPos + vec2(x*xoff,y*yoff)).xyz; 
+}
+void main() 
+{
+vec3 tl = f(-1, 1);
+vec3 tt = f( 0, 1);
+vec3 tr = f( 1, 1);
+vec3 mr = f( 1, 0);
+vec3 br = f( 1,-1);
+    if (tl == tt && tt == tr && tr == mr && mr == br)
+        { fColor = vec4(tl,1);}
+    else {fColor = texture(screenTexture, vTexPos); }
+}