diff options
Diffstat (limited to 'common/shaders/render/raymarching.wgsl')
| -rw-r--r-- | common/shaders/render/raymarching.wgsl | 79 |
1 files changed, 2 insertions, 77 deletions
diff --git a/common/shaders/render/raymarching.wgsl b/common/shaders/render/raymarching.wgsl index 7d05528..fb96348 100644 --- a/common/shaders/render/raymarching.wgsl +++ b/common/shaders/render/raymarching.wgsl @@ -3,8 +3,8 @@ // Required user-defined functions: // - df(vec3<f32>) -> f32 // Distance field for single-pass rendering (rayMarch, normal, shadow) -// - dfWithID(vec3<f32>) -> RayMarchResult -// Distance field with object ID for two-pass rendering (rayMarchWithID, normalWithID, shadowWithStoredDistance) +// +// For two-pass rendering with object IDs, see raymarching_id.wgsl // // Provided constants: // TOLERANCE, MAX_RAY_LENGTH, MAX_RAY_MARCHES, NORM_OFF @@ -64,78 +64,3 @@ fn shadow(lp: vec3<f32>, ld: vec3<f32>, mint: f32, maxt: f32) -> f32 { let sd = 1.0 - exp(-smul * max(t / maxt - soff, 0.0)); return sd; } - -// ============================================================================ -// Two-Pass Raymarching Support -// ============================================================================ -// Design note: RayMarchResult is passed/returned by value (not pointer). -// At 12 bytes (3×f32), return value optimization makes this efficient. -// See doc/CODING_STYLE.md for rationale. - -struct RayMarchResult { - distance: f32, // Distance to surface (MAX_RAY_LENGTH if miss) - distance_max: f32, // Total distance marched (for fog/AO) - object_id: f32, // Object identifier (0.0 = background) -} - -// Raymarch with object ID tracking. -fn rayMarchWithID(ro: vec3<f32>, rd: vec3<f32>, init: RayMarchResult) -> RayMarchResult { - var t = init.distance; - var result = init; - - for (var i = 0; i < MAX_RAY_MARCHES; i++) { - if (t > MAX_RAY_LENGTH) { - result.distance = MAX_RAY_LENGTH; - result.distance_max = MAX_RAY_LENGTH; - break; - } - let sample = dfWithID(ro + rd * t); - if (sample.distance < TOLERANCE) { - result.distance = t; - result.distance_max = t; - result.object_id = sample.object_id; - break; - } - t += sample.distance; - } - - return result; -} - -// Reconstruct world position from stored result. -fn reconstructPosition(ray_origin: vec3<f32>, ray_dir: vec3<f32>, result: RayMarchResult) -> vec3<f32> { - return ray_origin + ray_dir * result.distance; -} - -// Normal calculation using dfWithID. -fn normalWithID(pos: vec3<f32>) -> vec3<f32> { - let eps = vec2<f32>(NORM_OFF, 0.0); - var nor: vec3<f32>; - nor.x = dfWithID(pos + eps.xyy).distance - dfWithID(pos - eps.xyy).distance; - nor.y = dfWithID(pos + eps.yxy).distance - dfWithID(pos - eps.yxy).distance; - nor.z = dfWithID(pos + eps.yyx).distance - dfWithID(pos - eps.yyx).distance; - return normalize(nor); -} - -// Shadow using stored intersection distance. -fn shadowWithStoredDistance(lp: vec3<f32>, ld: vec3<f32>, stored_dist: f32) -> f32 { - let ds = 1.0 - 0.4; - var t = 0.01; - var nd = 1e6; - let soff = 0.05; - let smul = 1.5; - let MAX_SHD_MARCHES = 20; - - for (var i = 0; i < MAX_SHD_MARCHES; i++) { - let p = lp + ld * t; - let d = dfWithID(p).distance; - if (d < TOLERANCE || t >= stored_dist) { - let sd = 1.0 - exp(-smul * max(t / stored_dist - soff, 0.0)); - return select(mix(sd, 1.0, smoothstep(0.0, 0.025, nd)), sd, t >= stored_dist); - } - nd = min(nd, d); - t += ds * d; - } - let sd = 1.0 - exp(-smul * max(t / stored_dist - soff, 0.0)); - return sd; -} |
