cool dithering

godot/.mono/metadata/ide_messaging_meta.txt

@@ -1,2 +0,0 @@
-36673
-/home/squirrel/.local/bin/godot_mono

godot/assets/effects/dithering/CanvasLayer.tscn

@@ -4,7 +4,9 @@
 
 [sub_resource type="ShaderMaterial" id=1]
 shader = ExtResource( 1 )
-shader_param/param = 15.0
+shader_param/param = 13.0
+shader_param/scale = 2.0
+shader_param/grid = 4
 shader_param/anim_period = 1.65
 
 [node name="CanvasLayer" type="CanvasLayer"]

godot/assets/effects/dithering/screen_space_shader.tres

@@ -110,18 +110,57 @@ vec3 band_colors_preserve_hue_lum(vec3 rgb)
 	return hsv2rgb(hsv);
 }
 
+uniform float scale = 2.0;
+uniform int grid = 5;
+
+vec3 band_dither(vec3 rgb, vec2 uv)
+{
+	
+	uv *= (1.0 / scale);
+	int x = int(mod(uv.x, float(grid))) + 1;
+	int y = int(mod(uv.y, float(grid))) + 1;
+	
+	vec3 hsv = rgb2hsv(rgb);
+	
+	int g = int(round(mix(float(grid), float(2), fract(hsv.r * param))));
+	
+	
+	if (x % g == 0 && y % g == 0) {
+		hsv.r = ceil(hsv.r * param) / param;
+	} else {
+		hsv.r = floor(hsv.r * param) / param;		
+	}
+	vec3 lab = xyz2lab(rgb2xyz(rgb));
+	if (x % g == 0 && y % g == 0) {
+		lab.r = ceil(lab.r * (param / 100.0)) / (param / 100.0);
+	} else {
+		lab.r = floor(lab.r * (param / 100.0)) / (param / 100.0);
+	}
+	
+	// Into HSV
+	vec2 sv = rgb2hsv(xyz2rgb(lab2xyz(lab))).gb;
+	hsv.gb = sv;
+	
+	
+	return hsv2rgb(hsv);
+	
+}
+
 uniform float anim_period : hint_range(0.1, 5, 0.01);
 
 void fragment()
 {
 	vec3 rgb = textureLod(SCREEN_TEXTURE, SCREEN_UV, 0.0).rgb;
-	vec3 banded_preserved = band_colors_preserve_hue_lum(rgb);
+	vec3 banded_preserved = band_dither(rgb, FRAGCOORD.xy);
-	vec3 banded_nostalgia = band_colors(rgb);
+	//vec3 banded_nostalgia = band_colors(rgb);
-	float weight = mod(TIME, anim_period) / anim_period;
+	//float weight = mod(TIME, anim_period) / anim_period;
-	float double_weight = mod(TIME, anim_period*2.0) / (anim_period*2.0);
+	//float double_weight = mod(TIME, anim_period*2.0) / (anim_period*2.0);
-	weight = double_weight > 0.5 ? (1.-weight) : weight;
+	//weight = double_weight > 0.5 ? (1.-weight) : weight;
-	vec3 mixed = mix(banded_nostalgia, banded_preserved, weight);
+	//vec3 mixed = mix(banded_nostalgia, banded_preserved, weight);
-	COLOR.rgb = mixed;
+	//COLOR.rgb = mixed;
+	
+	
+	COLOR.rgb = banded_preserved;
 }
 
 "

godot/tests/dither.tscn

@@ -25,3 +25,11 @@ light_energy = 16.0
 light_indirect_energy = 1.306
 omni_range = 8.917
 omni_attenuation = 2.73208
+
+[node name="SpotLight" type="SpotLight" parent="."]
+transform = Transform( -0.999987, 5.82069e-11, 0.00514878, 0.00507827, 0.164927, 0.986293, -0.000849173, 0.986306, -0.164925, 0, 4.25661, -0.823411 )
+light_color = Color( 0.623529, 0.247059, 0.756863, 1 )
+light_energy = 30.0
+light_specular = 0.594
+spot_range = 13.9301
+spot_angle = 57.9366