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feat: add shadow coloring

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surv
2026-09-19 20:50:17 +02:00
parent 7c347a5abf
commit 908c13bfb0
8 changed files with 290 additions and 44 deletions
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src/shaders/colorize.wgsl
+104 -14
View File
@@ -20,32 +20,43 @@ struct Uniforms {
bailout_sq: f32,
is_julia: u32,
palette_id: u32,
shadow_palette_id: u32,
aa_level: u32,
kind: u32,
power: u32,
dc_offset: vec2<f32>,
phoenix_p: vec2<f32>,
lambda_l: vec2<f32>,
de_coloring: u32,
shadow: u32,
};
struct Light {
azimuth: f32,
altitude: f32,
color: u32,
_pad: u32
};
@group(0) @binding(0) var<uniform> u: Uniforms;
@group(0) @binding(1) var data_tex: texture_2d<f32>;
@group(0) @binding(2) var<uniform> lights: array<Light, 16>;
// Smooth cyclic palettes (Inigo Quilez cosine palettes). Must match the palette
// in mandelbrot.wgsl.
fn palette(id: u32, t: f32) -> vec3<f32> {
if (id == 4u) {
if id == 4u {
return vec3<f32>(t, t, t); // grayscale
}
let a = vec3<f32>(0.5, 0.5, 0.5);
let b = vec3<f32>(0.5, 0.5, 0.5);
var c = vec3<f32>(1.0, 1.0, 1.0);
var d = vec3<f32>(0.00, 0.10, 0.20); // 0: amber / blue
if (id == 1u) {
if id == 1u {
d = vec3<f32>(0.00, 0.33, 0.67); // rainbow
} else if (id == 2u) {
} else if id == 2u {
d = vec3<f32>(0.30, 0.20, 0.20); // warm ember
} else if (id == 3u) {
} else if id == 3u {
c = vec3<f32>(1.0, 1.0, 0.5);
d = vec3<f32>(0.80, 0.90, 0.30); // lime / magenta
}
@@ -62,17 +73,96 @@ fn vs_main(@builtin(vertex_index) idx: u32) -> @builtin(position) vec4<f32> {
return vec4<f32>(verts[idx], 0.0, 1.0);
}
fn load(x: i32, y: i32) -> vec3<f32> {
let dist = textureLoad(data_tex, vec2<i32>(x, y), 0).g;
return vec3<f32>(f32(x), f32(y), dist);
}
fn compute_light(normal: vec3<f32>, light: vec3<f32>) -> vec3<f32> {
return vec3<f32>(max(0., dot(normal, normalize(light))));
}
fn uncharted2tonemap(x: vec3<f32>) -> vec3<f32> {
let A = 0.15; // Shoulder strength
let B = 0.50; // Linear strength
let C = 0.10; // Linear angle
let D = 0.20; // Toe strength
let E = 0.02; // Toe numerator / shoarder angle/etc.
let F = 0.30; // Toe denominator
return ((x * (A * x + C * B) + D * E) / (x * (A * x + B) + D * F)) - E / F;
}
fn filmic(color: vec3<f32>, white_point: f32) -> vec3<f32> {
let exposure_bias = 2.0;
let curr = uncharted2tonemap(color * exposure_bias);
// Valeur blanche maximale de référence
let white_scale = vec3(1.0) / uncharted2tonemap(vec3(white_point));
return curr * white_scale;
}
fn s(color: vec3<f32>, k: f32, c: f32) -> vec3<f32> {
return 1. / (1. + exp(-k * (color - c)));
}
fn contrast(color: vec3<f32>, k: f32, c: f32) -> vec3<f32> {
let color_c = s(color, k, c);
return (color_c - s(vec3<f32>(0), k, c)) / (s(vec3<f32>(1), k, c) - s(vec3<f32>(0), k, c));
}
@fragment
fn fs_main(@builtin(position) pos: vec4<f32>) -> @location(0) vec4<f32> {
let d = textureLoad(data_tex, vec2<i32>(i32(pos.x), i32(pos.y)), 0);
let ci = d.r;
let de = d.g;
let interior_frac = d.b;
if u.shadow != 0u {
if textureLoad(data_tex, vec2<i32>(i32(pos.x), i32(pos.y)), 0).b != 0. {
return vec4<f32>(0.1, 0.1, 0.1, 1.0);
} else {
let d = array<vec3<f32>, 3>(load(i32(pos.x), i32(pos.y)), load(i32(pos.x + 1), i32(pos.y)), load(i32(pos.x), i32(pos.y + 1)));
let t = fract(ci * u.color_scale + u.color_offset);
var col = palette(u.palette_id, t) * de;
// Anti-alias the set boundary: fade toward black by the fraction of the
// pixel's sub-samples that landed in the interior.
col = col * (1.0 - interior_frac);
return vec4<f32>(col, 1.0);
let normal = normalize(cross(d[1] - d[0], d[2] - d[0]));
var color: vec3<f32>;
if u.shadow_palette_id == 0u {
color = compute_light(normal,vec3<f32>(.5, .5, .5)) + vec3<f32>(0.58, 0.85, 1.) * 0.2;
color = filmic(color, 2.5);
color = contrast(color, 4., 0.67);
} else if u.shadow_palette_id == 1u {
color = compute_light(normal, vec3<f32>(0., .5, .5)) * vec3<f32>(1., 0.5, 0.5) + compute_light(normal, vec3<f32>(0.5, 0., .5)) * vec3<f32>(0.5, 1., 1.);
color = filmic(color, 4.2);
} else {
color = vec3<f32>(0);
var light_count = 0;
for (var i = 0u ; i < 16; i++) {
let light_color = unpack4x8unorm(lights[i].color);
if any(light_color != vec4<f32>(0)) {
light_count += 1;
}
color += compute_light(normal, vec3<f32>(
cos(lights[i].azimuth) * cos(lights[i].altitude),
sin(lights[i].azimuth) * cos(lights[i].altitude),
sin(lights[i].altitude))) * light_color.xyz * light_color.a;
}
color = filmic(color, 1. + f32(light_count));
}
return vec4<f32>(color, 1.0);
}
} else {
let d = textureLoad(data_tex, vec2<i32>(i32(pos.x), i32(pos.y)), 0);
let ci = d.r;
let de = d.g;
let interior_frac = d.b;
let t = fract(ci * u.color_scale + u.color_offset);
var col = palette(u.palette_id, t) * de;
// Anti-alias the set boundary: fade toward black by the fraction of the
// pixel's sub-samples that landed in the interior.
col = col * (1.0 - interior_frac);
return vec4<f32>(col, 1.0);
}
}
src/shaders/mandelbrot.wgsl
+10 -3
View File
@@ -21,6 +21,7 @@ struct Uniforms {
bailout_sq: f32,
is_julia: u32,
palette_id: u32,
shadow_palette_id: u32,
aa_level: u32,
// Iteration formula (see the KIND_* constants below).
kind: u32,
@@ -35,6 +36,8 @@ struct Uniforms {
lambda_l: vec2<f32>,
// 0 = escape-time coloring, 1 = distance-estimation shading.
de_coloring: u32,
// 0 = classic colors, 1 = shadows
shadow: u32,
};
const KIND_MANDELBROT: u32 = 0u;
@@ -158,7 +161,7 @@ fn advance_delta(z: vec2<f32>, e: vec2<f32>) -> vec2<f32> {
return vec2<f32>(sq.x, -2.0 * (z.x * da + e.x * abs_yf));
} else if u.kind == KIND_LAMBDA {
// Lambda map: z^{n+1} = λ·z·(1-z). Delta: e = λ·e·(1-2z-e).
let one_minus_2z_minus_e = vec2<f32>(1.0 - 2.0*z.x - e.x, -2.0*z.y - e.y);
let one_minus_2z_minus_e = vec2<f32>(1.0 - 2.0 * z.x - e.x, -2.0 * z.y - e.y);
return cmul(u.lambda_l, cmul(e, one_minus_2z_minus_e));
}
return 2.0 * cmul(z, e) + cmul(e, e); // Mandelbrot (and Phoenix square part)
@@ -179,7 +182,7 @@ fn fprime(z: vec2<f32>) -> vec2<f32> {
return f32(p) * zk;
} else if u.kind == KIND_LAMBDA {
// Lambda: f'(z) = λ·(1-2z).
return cmul(u.lambda_l, vec2<f32>(1.0 - 2.0*z.x, -2.0*z.y));
return cmul(u.lambda_l, vec2<f32>(1.0 - 2.0 * z.x, -2.0 * z.y));
}
return 2.0 * z;
}
@@ -326,7 +329,11 @@ fn iterate_sample(offset: vec2<f32>, px: f32) -> Sample {
let zmag = sqrt(max(z2, 1.0));
let dzmag = sqrt(max(dot(dz, dz), 1e-20));
let d = zmag * log(zmag) / dzmag;
de = clamp(d / max(px, 1e-30), 0.0, 1.0);
var max_de = 1.;
if u.shadow != 0u {
max_de = 1000.;
}
de = clamp(d / max(px, 1e-30), 0.0, max_de);
}
return Sample(ci, de, true);
}