init

assets/shaders/pixelart.glsl

@@ -0,0 +1,19 @@
+// Fragment-stage only (uses screen-space derivatives).
+// "Sharp bilinear": crisp texel edges when magnified, antialiased boundaries
+// and correct mip selection when minified (unlike GL_NEAREST shimmer).
+vec4 sharpSample(sampler2D tex, vec2 uv) {
+    vec2 size = vec2(textureSize(tex, 0));
+    vec2 px = uv * size;
+    vec2 seam = floor(px + 0.5);
+    vec2 fw = max(fwidth(px), vec2(1e-5));
+    px = seam + clamp((px - seam) / fw, -0.5, 0.5);
+    return textureGrad(tex, px / size, dFdx(uv), dFdy(uv));
+}
+vec4 sharpSampleArray(sampler2DArray tex, vec2 uv, float layer) {
+    vec2 size = vec2(textureSize(tex, 0).xy);
+    vec2 px = uv * size;
+    vec2 seam = floor(px + 0.5);
+    vec2 fw = max(fwidth(px), vec2(1e-5));
+    px = seam + clamp((px - seam) / fw, -0.5, 0.5);
+    return textureGrad(tex, vec3(px / size, layer), dFdx(uv), dFdy(uv));
+}