mirror of
https://github.com/Orama-Interactive/Pixelorama.git
synced 2025-02-26 15:33:13 +00:00
105 lines
3.3 KiB
Text
105 lines
3.3 KiB
Text
shader_type canvas_item;
|
|
render_mode unshaded;
|
|
|
|
uniform sampler2D gradient_texture;
|
|
uniform sampler2D dither_texture;
|
|
uniform sampler2D offset_texture;
|
|
uniform sampler2D selection;
|
|
uniform vec2 image_size = vec2(64.0);
|
|
uniform float position : hint_range(-0.5, 0.5) = 0.0;
|
|
uniform float size : hint_range(0.01, 2.0) = 1.0;
|
|
uniform float angle : hint_range(0.0, 360.0) = 0.0;
|
|
uniform vec2 center = vec2(0.5);
|
|
uniform vec2 radius = vec2(1.0);
|
|
uniform int shape = 0; // 0 = linear, 1 = radial
|
|
uniform int repeat = 0; // 0 = none, 1 = repeat, 2 = mirrored, 3 = truncate
|
|
uniform int pixel_size : hint_range(2, 16) = 2;
|
|
uniform int n_of_colors = 2;
|
|
|
|
|
|
float modify_uv(vec2 uv) {
|
|
float modified_uv;
|
|
if (shape == 0) { // Linear
|
|
vec2 uv_offsetted = uv - 0.5;
|
|
float angle_cos = cos(radians(angle));
|
|
float angle_sin = sin(radians(angle));
|
|
modified_uv = uv_offsetted.x * angle_cos - uv_offsetted.y * angle_sin;
|
|
modified_uv /= abs(angle_cos) + abs(angle_sin);
|
|
modified_uv /= size;
|
|
float pivot = position / size;
|
|
modified_uv -= pivot - 0.5;
|
|
}
|
|
else { // Radial
|
|
vec2 uv_offsetted = uv * 2.0 - 1.0;
|
|
uv_offsetted -= (center * 2.0) - vec2(1.0);
|
|
uv_offsetted /= radius;
|
|
modified_uv = length(uv_offsetted);
|
|
}
|
|
return modified_uv;
|
|
}
|
|
|
|
|
|
float mirror_fract(float uv) {
|
|
int sign_uv = (int(sign(uv)) - 1) / 2; // returns -1 for negative sign and 0 for positive
|
|
if (int((uv)) % 2 == sign_uv)
|
|
uv = fract(uv);
|
|
else
|
|
uv = fract(1.0 - uv);
|
|
|
|
return uv;
|
|
}
|
|
|
|
// Logic taken from https://godotshaders.com/shader/dither-gradient-shader/
|
|
float dither(vec2 uv, float modified_uv) {
|
|
float uv_lower = floor(modified_uv);
|
|
float uv_upper = floor(modified_uv) + 1.0;
|
|
float threshold = texture(dither_texture, uv * (image_size / float(pixel_size))).r;
|
|
float ramp_val = modified_uv < threshold ? 0.0 : 1.0;
|
|
// sample at the lower bound colour if ramp_val is 0.0, upper bound color if 1.0
|
|
float col_sample = mix(uv_lower, uv_upper, ramp_val);
|
|
return col_sample;
|
|
}
|
|
|
|
|
|
void fragment() {
|
|
vec4 original_color = texture(TEXTURE, UV);
|
|
vec4 selection_color = texture(selection, UV);
|
|
float modified_uv = modify_uv(UV);
|
|
if (repeat == 1)
|
|
modified_uv = fract(modified_uv);
|
|
else if (repeat == 2)
|
|
modified_uv = mirror_fract(modified_uv);
|
|
|
|
vec4 output;
|
|
// Note for the future, please remember to change 100 to n_of_colors when we
|
|
// use GLES3 for the Web version. A constant number is used to make it work in WebGL 1.0.
|
|
for (int i = 1; i <= 100; i++) {
|
|
if(i > n_of_colors) {
|
|
break;
|
|
}
|
|
float colors_minus = float(n_of_colors - 1);
|
|
float off = texture(offset_texture, vec2(float(i) / colors_minus)).r;
|
|
float off_prev = texture(offset_texture, vec2(float(i - 1) / colors_minus)).r;
|
|
vec4 first = texture(gradient_texture, vec2(float((i - 1)) / colors_minus));
|
|
vec4 second = texture(gradient_texture, vec2(float(i) / colors_minus));
|
|
if (modified_uv < off_prev) {
|
|
if (i == 1) {
|
|
output = first;
|
|
}
|
|
continue;
|
|
}
|
|
if (modified_uv > off) {
|
|
if (i == n_of_colors) {
|
|
output = second;
|
|
}
|
|
continue;
|
|
}
|
|
float uvt = (modified_uv - off_prev) / (off - off_prev);
|
|
float col_sample = dither(UV, uvt);
|
|
output = mix(first, second, col_sample);
|
|
}
|
|
if (repeat == 3)
|
|
output.a = min(step(modified_uv, 1.0) * step(0.0, modified_uv), output.a);
|
|
output = mix(original_color, output, output.a);
|
|
COLOR = mix(original_color, output, selection_color.a);
|
|
}
|