initial commit

Assets/Scripts/Shaders/psx.gdshader

@@ -0,0 +1,89 @@
+shader_type canvas_item;
+
+uniform sampler2D screen_texture : hint_screen_texture;
+uniform float pixel_resolution : hint_range(64.0, 512.0) = 240.0;
+uniform int color_steps : hint_range(2, 64) = 16;
+uniform float noise_strength : hint_range(0.0, 1.0) = 0.1;
+uniform bool enable_dither = true;
+uniform float dither_strength : hint_range(0.0, 1.0) = 0.3;
+
+uniform bool enable_glow = true;
+uniform float glow_strength : hint_range(0.0, 1.0) = 0.4;
+uniform float glow_spread : hint_range(0.001, 0.01) = 0.005;
+
+uniform bool enable_vintage = true;  //  Toggle
+uniform float vintage_strength : hint_range(0.0, 1.0) = 0.8;
+
+float random(vec2 co) {
+	return fract(sin(dot(co.xy, vec2(12.9898, 78.233))) * 43758.5453);
+}
+
+float bayer_dither(vec2 pos) {
+	int x = int(mod(pos.x, 4.0));
+	int y = int(mod(pos.y, 4.0));
+	int index = x + y * 4;
+
+	float bayer[16] = float[](
+		0.0, 8.0, 2.0, 10.0,
+		12.0, 4.0, 14.0, 6.0,
+		3.0, 11.0, 1.0, 9.0,
+		15.0, 7.0, 13.0, 5.0
+	);
+
+	return bayer[index] / 16.0;
+}
+
+vec3 get_glow(vec2 uv) {
+	vec3 col = vec3(0.0);
+	float total = 0.0;
+
+	for (int x = -1; x <= 1; x++) {
+		for (int y = -1; y <= 1; y++) {
+			vec2 offset = vec2(float(x), float(y)) * glow_spread;
+			col += texture(screen_texture, uv + offset).rgb;
+			total += 1.0;
+		}
+	}
+	return col / total;
+}
+
+vec3 apply_black_vintage_edges(vec3 color, vec2 uv) {
+	// Distance from screen center
+	float dist = distance(uv, vec2(0.5));
+
+	// Mask: only affects edges
+	float edge_mask = smoothstep(0.4, 0.8, dist);
+
+	// Blend edges to black
+	color = mix(color, vec3(0.0), edge_mask * vintage_strength);
+
+	return color;
+}
+
+void fragment() {
+	vec2 pixel_uv = floor(UV * pixel_resolution) / pixel_resolution;
+	vec3 color = texture(screen_texture, pixel_uv).rgb;
+
+	if (enable_glow) {
+		vec3 blurred = get_glow(UV);
+		color += blurred * glow_strength;
+	}
+
+	float steps = float(color_steps);
+	color = floor(color * steps + 0.5) / steps;
+
+	float noise = (random(UV + TIME) - 0.5) * noise_strength;
+	color += noise;
+
+	if (enable_dither) {
+		float threshold = bayer_dither(FRAGCOORD.xy);
+		color += (dither_strength * (threshold - 0.5));
+	}
+
+	//  Black vintage only on edges
+	if (enable_vintage) {
+		color = apply_black_vintage_edges(color, UV);
+	}
+
+	COLOR.rgb = clamp(color, 0.0, 1.0);
+}