From 74517a52da4e35cd6804b7ff1d2ebccd7d139390 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Matej=20Kozlovsk=C3=BD?= Date: Thu, 15 Oct 2026 15:37:14 +0200 Subject: [PATCH] Cryptomatte: the GPU path skips the ID colours unless the Colors display reads them, and the CPU path keys the layer in place instead of copying it (#473) Output is bit-identical (all displays, CPU and GPU). At 2560x1440 with 3 ranks and 2000 IDs on 8 cores the CPU effect drops from ~87-135 ms to ~44-54 ms and the GPU path's aux reduction from 38 to 8 ms for Matte, Preview and Matte Only. --- crates/effects/src/channel3d.rs | 28 +++++++++++++++++++++++----- crates/effects/src/lib.rs | 2 +- crates/gpu/src/fx_depth.rs | 5 ++++- 3 files changed, 28 insertions(+), 7 deletions(-) diff --git a/crates/effects/src/channel3d.rs b/crates/effects/src/channel3d.rs index 7884e808..32fda883 100644 --- a/crates/effects/src/channel3d.rs +++ b/crates/effects/src/channel3d.rs @@ -413,10 +413,16 @@ fn crypto_colors(planes: &RankPlanes, i: usize) -> [f32; 3] { /// selection's coverage (A), computed in parallel with the rank planes resolved once. The GPU /// effect uploads this image and samples it per layer pixel. pub fn crypto_aux_image(a: &AuxChannels, layer: &str, sel: &[u32]) -> Image { + crypto_aux_image_with(a, layer, sel, true) +} + +/// [`crypto_aux_image`]; with `colors` false the RGB stays 0 and only the matte (A) is computed, +/// for the displays that never read the ID colours. +pub fn crypto_aux_image_with(a: &AuxChannels, layer: &str, sel: &[u32], colors: bool) -> Image { let planes = a.crypto_rank_planes(layer); let mut img = Image::new(a.width, a.height); img.data.par_iter_mut().enumerate().for_each(|(i, px)| { - let c = crypto_colors(&planes, i); + let c = if colors { crypto_colors(&planes, i) } else { [0.0; 3] }; *px = [c[0], c[1], c[2], crypto_matte(&planes, sel, i)]; }); img @@ -436,7 +442,6 @@ fn cryptomatte(ctx: &EffectCtx, mut b: Buf) -> Buf { let display = ctx.params.e("display"); let matte_only = ctx.params.b("matteOnly"); let planes = a.crypto_rank_planes(&layer); - let src = b.img.clone(); b.img.data.par_iter_mut().enumerate().for_each(|(i, px)| { let m = idx[i].map_or(0.0, |k| crypto_matte(&planes, &sel, k)); if matte_only { @@ -450,11 +455,11 @@ fn cryptomatte(ctx: &EffectCtx, mut b: Buf) -> Buf { let c = c.map(|v| v * (1.0 - 0.5 * m) + 0.5 * m); [c[0], c[1], c[2], 1.0] } - // Matte: the layer keyed by the selection. - 1 => src.data[i].map(|v| v * m), + // Matte: the layer keyed by the selection (each pixel only reads itself, so no copy). + 1 => px.map(|v| v * m), // Preview: the layer with the selection tinted. _ => { - let s = src.data[i]; + let s = *px; [s[0] * (1.0 - 0.5 * m) + 0.5 * m * s[3], s[1] * (1.0 - 0.5 * m) + 0.5 * m * s[3], s[2] * (1.0 - 0.5 * m), s[3]] } }; @@ -835,6 +840,19 @@ mod tests { } } + /// Without the ID colours the matte (A) is bit-identical and the RGB is 0, on the edge values. + #[test] + fn crypto_aux_image_without_colors_keeps_the_matte() { + let a = edge_aux(true); + let sel = edge_selection(); + let full = crypto_aux_image(&a, "CryptoObject", &sel); + let matte = crypto_aux_image_with(&a, "CryptoObject", &sel, false); + for (f, m) in full.data.iter().zip(&matte.data) { + assert_eq!(f[3].to_bits(), m[3].to_bits()); + assert_eq!(m[..3], [0.0; 3]); + } + } + /// The CPU effect on a 20×10 layer over the 6×2 edge aux: pixels inside the aux area match /// the lookup by name bit for bit in every display mode, pixels outside it (no aux index) /// get an empty matte and no ID colour. diff --git a/crates/effects/src/lib.rs b/crates/effects/src/lib.rs index 40ed79a7..4c1ea60b 100644 --- a/crates/effects/src/lib.rs +++ b/crates/effects/src/lib.rs @@ -110,7 +110,7 @@ pub use time_fx::{PixelMotion, TimewarpPlan, TwStep, pmb_plan, posterized_time, // effectcraft-gpu fx_tone. pub use ocio::color_stabilizer_maps; // GPU effects, part B (3D Channel, Immersive Video, colour management, simulation render passes). -pub use channel3d::{CRYPTO_LAYERS, crypto_aux_image, id_color, selection_hashes}; +pub use channel3d::{CRYPTO_LAYERS, crypto_aux_image, crypto_aux_image_with, id_color, selection_hashes}; pub use ocio::{ColorOp, Straight, Tf, color_program}; pub use sim::{Acc, Blob, Bubble, Post, Shape, Sprite, SpritePlan, Tint, bubble_list, drizzle_drops, mercury_blobs, sprite_plan}; pub use sim2::{ diff --git a/crates/gpu/src/fx_depth.rs b/crates/gpu/src/fx_depth.rs index 4931afe2..a74ff717 100644 --- a/crates/gpu/src/fx_depth.rs +++ b/crates/gpu/src/fx_depth.rs @@ -278,7 +278,10 @@ fn cryptomatte(e: &mut Enc, ctx: &EffectCtx, b: GBuf, a: &AuxChannels) -> Option let sel = effectcraft_effects::selection_hashes(pr.s("selection"), manifest); // Per aux pixel: coverage-weighted ID colours (RGB) and the selection's coverage (A), on all // cores with the rank planes resolved once. - let img = effectcraft_effects::crypto_aux_image(a, &layer, &sel); + // The ID colours are only read by the Colors display; Matte, Preview and Matte Only need the + // matte alone. + let colors = pr.e("display") == 0 && !pr.b("matteOnly"); + let img = effectcraft_effects::crypto_aux_image_with(a, &layer, &sel, colors); let tex = e.g.upload_image(&img)?; let plane = lookup(e, &b, a, &tex, [0.5, 0.5], [0.0; 4]); let mut p = op(7);