From ba832d83b2dafcdbb79b93b1e97fd518c12b97bf Mon Sep 17 00:00:00 2001 From: jfons Date: Mon, 4 Apr 2022 16:10:22 +0200 Subject: Initial TAA implementation Initial TAA support based on the implementation in Spartan Engine. Motion vectors are correctly generated for camera and mesh movement, but there is no support for other things like particles or skeleton deformations. --- .../rendering/renderer_rd/shaders/taa_resolve.glsl | 393 +++++++++++++++++++++ 1 file changed, 393 insertions(+) create mode 100644 servers/rendering/renderer_rd/shaders/taa_resolve.glsl (limited to 'servers/rendering/renderer_rd/shaders/taa_resolve.glsl') diff --git a/servers/rendering/renderer_rd/shaders/taa_resolve.glsl b/servers/rendering/renderer_rd/shaders/taa_resolve.glsl new file mode 100644 index 0000000000..a1a77b95aa --- /dev/null +++ b/servers/rendering/renderer_rd/shaders/taa_resolve.glsl @@ -0,0 +1,393 @@ +/////////////////////////////////////////////////////////////////////////////////// +// Copyright(c) 2016-2022 Panos Karabelas +// +// Permission is hereby granted, free of charge, to any person obtaining a copy +// of this software and associated documentation files (the "Software"), to deal +// in the Software without restriction, including without limitation the rights +// to use, copy, modify, merge, publish, distribute, sublicense, and / or sell +// copies of the Software, and to permit persons to whom the Software is furnished +// to do so, subject to the following conditions : +// +// The above copyright notice and this permission notice shall be included in +// all copies or substantial portions of the Software. +// +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS +// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE AUTHORS OR +// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER +// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN +// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +/////////////////////////////////////////////////////////////////////////////////// +// File changes (yyyy-mm-dd) +// 2022-05-06: Panos Karabelas: first commit +// 2020-12-05: Joan Fons: convert to Vulkan and Godot +/////////////////////////////////////////////////////////////////////////////////// + +#[compute] + +#version 450 + +#VERSION_DEFINES + +// Based on Spartan Engine's TAA implementation https://github.com/PanosK92/SpartanEngine/blob/master/Data/shaders/temporal_antialiasing.hlsl + +#define USE_SUBGROUPS + +#define GROUP_SIZE 8 +#define FLT_MIN 0.00000001 +#define FLT_MAX 32767.0 +#define RPC_9 0.11111111111 +#define RPC_16 0.0625 + +#ifdef USE_SUBGROUPS +layout(local_size_x = GROUP_SIZE, local_size_y = GROUP_SIZE, local_size_z = 1) in; +#endif + +layout(rgba16f, set = 0, binding = 0) uniform restrict readonly image2D color_buffer; +layout(set = 0, binding = 1) uniform sampler2D depth_buffer; +layout(rg16f, set = 0, binding = 2) uniform restrict readonly image2D velocity_buffer; +layout(rg16f, set = 0, binding = 3) uniform restrict readonly image2D last_velocity_buffer; +layout(set = 0, binding = 4) uniform sampler2D history_buffer; +layout(rgba16f, set = 0, binding = 5) uniform restrict writeonly image2D output_buffer; + +layout(push_constant, std430) uniform Params { + vec2 resolution; + float disocclusion_threshold; // 0.1 / max(params.resolution.x, params.resolution.y + float disocclusion_scale; +} +params; + +const ivec2 kOffsets3x3[9] = { + ivec2(-1, -1), + ivec2(0, -1), + ivec2(1, -1), + ivec2(-1, 0), + ivec2(0, 0), + ivec2(1, 0), + ivec2(-1, 1), + ivec2(0, 1), + ivec2(1, 1), +}; + +/*------------------------------------------------------------------------------ + THREAD GROUP SHARED MEMORY (LDS) +------------------------------------------------------------------------------*/ + +const int kBorderSize = 1; +const int kGroupSize = GROUP_SIZE; +const int kTileDimension = kGroupSize + kBorderSize * 2; +const int kTileDimension2 = kTileDimension * kTileDimension; + +vec3 reinhard(vec3 hdr) { + return hdr / (hdr + 1.0); +} +vec3 reinhard_inverse(vec3 sdr) { + return sdr / (1.0 - sdr); +} + +float get_depth(ivec2 thread_id) { + return texelFetch(depth_buffer, thread_id, 0).r; +} + +#ifdef USE_SUBGROUPS +shared vec3 tile_color[kTileDimension][kTileDimension]; +shared float tile_depth[kTileDimension][kTileDimension]; + +vec3 load_color(uvec2 group_thread_id) { + group_thread_id += kBorderSize; + return tile_color[group_thread_id.x][group_thread_id.y]; +} + +void store_color(uvec2 group_thread_id, vec3 color) { + tile_color[group_thread_id.x][group_thread_id.y] = color; +} + +float load_depth(uvec2 group_thread_id) { + group_thread_id += kBorderSize; + return tile_depth[group_thread_id.x][group_thread_id.y]; +} + +void store_depth(uvec2 group_thread_id, float depth) { + tile_depth[group_thread_id.x][group_thread_id.y] = depth; +} + +void store_color_depth(uvec2 group_thread_id, ivec2 thread_id) { + // out of bounds clamp + thread_id = clamp(thread_id, ivec2(0, 0), ivec2(params.resolution) - ivec2(1, 1)); + + store_color(group_thread_id, imageLoad(color_buffer, thread_id).rgb); + store_depth(group_thread_id, get_depth(thread_id)); +} + +void populate_group_shared_memory(uvec2 group_id, uint group_index) { + // Populate group shared memory + ivec2 group_top_left = ivec2(group_id) * kGroupSize - kBorderSize; + if (group_index < (kTileDimension2 >> 2)) { + ivec2 group_thread_id_1 = ivec2(group_index % kTileDimension, group_index / kTileDimension); + ivec2 group_thread_id_2 = ivec2((group_index + (kTileDimension2 >> 2)) % kTileDimension, (group_index + (kTileDimension2 >> 2)) / kTileDimension); + ivec2 group_thread_id_3 = ivec2((group_index + (kTileDimension2 >> 1)) % kTileDimension, (group_index + (kTileDimension2 >> 1)) / kTileDimension); + ivec2 group_thread_id_4 = ivec2((group_index + kTileDimension2 * 3 / 4) % kTileDimension, (group_index + kTileDimension2 * 3 / 4) / kTileDimension); + + store_color_depth(group_thread_id_1, group_top_left + group_thread_id_1); + store_color_depth(group_thread_id_2, group_top_left + group_thread_id_2); + store_color_depth(group_thread_id_3, group_top_left + group_thread_id_3); + store_color_depth(group_thread_id_4, group_top_left + group_thread_id_4); + } + + // Wait for group threads to load store data. + groupMemoryBarrier(); + barrier(); +} +#else +vec3 load_color(uvec2 screen_pos) { + return imageLoad(color_buffer, ivec2(screen_pos)).rgb; +} + +float load_depth(uvec2 screen_pos) { + return get_depth(ivec2(screen_pos)); +} +#endif + +/*------------------------------------------------------------------------------ + VELOCITY +------------------------------------------------------------------------------*/ + +void depth_test_min(uvec2 pos, inout float min_depth, inout uvec2 min_pos) { + float depth = load_depth(pos); + + if (depth < min_depth) { + min_depth = depth; + min_pos = pos; + } +} + +// Returns velocity with closest depth (3x3 neighborhood) +void get_closest_pixel_velocity_3x3(in uvec2 group_pos, uvec2 group_top_left, out vec2 velocity) { + float min_depth = 1.0; + uvec2 min_pos = group_pos; + + depth_test_min(group_pos + kOffsets3x3[0], min_depth, min_pos); + depth_test_min(group_pos + kOffsets3x3[1], min_depth, min_pos); + depth_test_min(group_pos + kOffsets3x3[2], min_depth, min_pos); + depth_test_min(group_pos + kOffsets3x3[3], min_depth, min_pos); + depth_test_min(group_pos + kOffsets3x3[4], min_depth, min_pos); + depth_test_min(group_pos + kOffsets3x3[5], min_depth, min_pos); + depth_test_min(group_pos + kOffsets3x3[6], min_depth, min_pos); + depth_test_min(group_pos + kOffsets3x3[7], min_depth, min_pos); + depth_test_min(group_pos + kOffsets3x3[8], min_depth, min_pos); + + // Velocity out + velocity = imageLoad(velocity_buffer, ivec2(group_top_left + min_pos)).xy; +} + +/*------------------------------------------------------------------------------ + HISTORY SAMPLING +------------------------------------------------------------------------------*/ + +vec3 sample_catmull_rom_9(sampler2D stex, vec2 uv, vec2 resolution) { + // Source: https://gist.github.com/TheRealMJP/c83b8c0f46b63f3a88a5986f4fa982b1 + // License: https://gist.github.com/TheRealMJP/bc503b0b87b643d3505d41eab8b332ae + + // We're going to sample a a 4x4 grid of texels surrounding the target UV coordinate. We'll do this by rounding + // down the sample location to get the exact center of our "starting" texel. The starting texel will be at + // location [1, 1] in the grid, where [0, 0] is the top left corner. + vec2 sample_pos = uv * resolution; + vec2 texPos1 = floor(sample_pos - 0.5f) + 0.5f; + + // Compute the fractional offset from our starting texel to our original sample location, which we'll + // feed into the Catmull-Rom spline function to get our filter weights. + vec2 f = sample_pos - texPos1; + + // Compute the Catmull-Rom weights using the fractional offset that we calculated earlier. + // These equations are pre-expanded based on our knowledge of where the texels will be located, + // which lets us avoid having to evaluate a piece-wise function. + vec2 w0 = f * (-0.5f + f * (1.0f - 0.5f * f)); + vec2 w1 = 1.0f + f * f * (-2.5f + 1.5f * f); + vec2 w2 = f * (0.5f + f * (2.0f - 1.5f * f)); + vec2 w3 = f * f * (-0.5f + 0.5f * f); + + // Work out weighting factors and sampling offsets that will let us use bilinear filtering to + // simultaneously evaluate the middle 2 samples from the 4x4 grid. + vec2 w12 = w1 + w2; + vec2 offset12 = w2 / (w1 + w2); + + // Compute the final UV coordinates we'll use for sampling the texture + vec2 texPos0 = texPos1 - 1.0f; + vec2 texPos3 = texPos1 + 2.0f; + vec2 texPos12 = texPos1 + offset12; + + texPos0 /= resolution; + texPos3 /= resolution; + texPos12 /= resolution; + + vec3 result = vec3(0.0f, 0.0f, 0.0f); + + result += textureLod(stex, vec2(texPos0.x, texPos0.y), 0.0).xyz * w0.x * w0.y; + result += textureLod(stex, vec2(texPos12.x, texPos0.y), 0.0).xyz * w12.x * w0.y; + result += textureLod(stex, vec2(texPos3.x, texPos0.y), 0.0).xyz * w3.x * w0.y; + + result += textureLod(stex, vec2(texPos0.x, texPos12.y), 0.0).xyz * w0.x * w12.y; + result += textureLod(stex, vec2(texPos12.x, texPos12.y), 0.0).xyz * w12.x * w12.y; + result += textureLod(stex, vec2(texPos3.x, texPos12.y), 0.0).xyz * w3.x * w12.y; + + result += textureLod(stex, vec2(texPos0.x, texPos3.y), 0.0).xyz * w0.x * w3.y; + result += textureLod(stex, vec2(texPos12.x, texPos3.y), 0.0).xyz * w12.x * w3.y; + result += textureLod(stex, vec2(texPos3.x, texPos3.y), 0.0).xyz * w3.x * w3.y; + + return max(result, 0.0f); +} + +/*------------------------------------------------------------------------------ + HISTORY CLIPPING +------------------------------------------------------------------------------*/ + +// Based on "Temporal Reprojection Anti-Aliasing" - https://github.com/playdeadgames/temporal +vec3 clip_aabb(vec3 aabb_min, vec3 aabb_max, vec3 p, vec3 q) { + vec3 r = q - p; + vec3 rmax = (aabb_max - p.xyz); + vec3 rmin = (aabb_min - p.xyz); + + if (r.x > rmax.x + FLT_MIN) + r *= (rmax.x / r.x); + if (r.y > rmax.y + FLT_MIN) + r *= (rmax.y / r.y); + if (r.z > rmax.z + FLT_MIN) + r *= (rmax.z / r.z); + + if (r.x < rmin.x - FLT_MIN) + r *= (rmin.x / r.x); + if (r.y < rmin.y - FLT_MIN) + r *= (rmin.y / r.y); + if (r.z < rmin.z - FLT_MIN) + r *= (rmin.z / r.z); + + return p + r; +} + +// Clip history to the neighbourhood of the current sample +vec3 clip_history_3x3(uvec2 group_pos, vec3 color_history, vec2 velocity_closest) { + // Sample a 3x3 neighbourhood + vec3 s1 = load_color(group_pos + kOffsets3x3[0]); + vec3 s2 = load_color(group_pos + kOffsets3x3[1]); + vec3 s3 = load_color(group_pos + kOffsets3x3[2]); + vec3 s4 = load_color(group_pos + kOffsets3x3[3]); + vec3 s5 = load_color(group_pos + kOffsets3x3[4]); + vec3 s6 = load_color(group_pos + kOffsets3x3[5]); + vec3 s7 = load_color(group_pos + kOffsets3x3[6]); + vec3 s8 = load_color(group_pos + kOffsets3x3[7]); + vec3 s9 = load_color(group_pos + kOffsets3x3[8]); + + // Compute min and max (with an adaptive box size, which greatly reduces ghosting) + vec3 color_avg = (s1 + s2 + s3 + s4 + s5 + s6 + s7 + s8 + s9) * RPC_9; + vec3 color_avg2 = ((s1 * s1) + (s2 * s2) + (s3 * s3) + (s4 * s4) + (s5 * s5) + (s6 * s6) + (s7 * s7) + (s8 * s8) + (s9 * s9)) * RPC_9; + float box_size = mix(0.0f, 2.5f, smoothstep(0.02f, 0.0f, length(velocity_closest))); + vec3 dev = sqrt(abs(color_avg2 - (color_avg * color_avg))) * box_size; + vec3 color_min = color_avg - dev; + vec3 color_max = color_avg + dev; + + // Variance clipping + vec3 color = clip_aabb(color_min, color_max, clamp(color_avg, color_min, color_max), color_history); + + // Clamp to prevent NaNs + color = clamp(color, FLT_MIN, FLT_MAX); + + return color; +} + +/*------------------------------------------------------------------------------ + TAA +------------------------------------------------------------------------------*/ + +const vec3 lumCoeff = vec3(0.299f, 0.587f, 0.114f); + +float luminance(vec3 color) { + return max(dot(color, lumCoeff), 0.0001f); +} + +float get_factor_disocclusion(vec2 uv_reprojected, vec2 velocity) { + vec2 velocity_previous = imageLoad(last_velocity_buffer, ivec2(uv_reprojected * params.resolution)).xy; + vec2 velocity_texels = velocity * params.resolution; + vec2 prev_velocity_texels = velocity_previous * params.resolution; + float disocclusion = length(prev_velocity_texels - velocity_texels) - params.disocclusion_threshold; + return clamp(disocclusion * params.disocclusion_scale, 0.0, 1.0); +} + +vec3 temporal_antialiasing(uvec2 pos_group_top_left, uvec2 pos_group, uvec2 pos_screen, vec2 uv, sampler2D tex_history) { + // Get the velocity of the current pixel + vec2 velocity = imageLoad(velocity_buffer, ivec2(pos_screen)).xy; + + // Get reprojected uv + vec2 uv_reprojected = uv - velocity; + + // Get input color + vec3 color_input = load_color(pos_group); + + // Get history color (catmull-rom reduces a lot of the blurring that you get under motion) + vec3 color_history = sample_catmull_rom_9(tex_history, uv_reprojected, params.resolution).rgb; + + // Clip history to the neighbourhood of the current sample (fixes a lot of the ghosting). + vec2 velocity_closest = vec2(0.0); // This is best done by using the velocity with the closest depth. + get_closest_pixel_velocity_3x3(pos_group, pos_group_top_left, velocity_closest); + color_history = clip_history_3x3(pos_group, color_history, velocity_closest); + + // Compute blend factor + float blend_factor = RPC_16; // We want to be able to accumulate as many jitter samples as we generated, that is, 16. + { + // If re-projected UV is out of screen, converge to current color immediatel + float factor_screen = any(lessThan(uv_reprojected, vec2(0.0))) || any(greaterThan(uv_reprojected, vec2(1.0))) ? 1.0 : 0.0; + + // Increase blend factor when there is disocclusion (fixes a lot of the remaining ghosting). + float factor_disocclusion = get_factor_disocclusion(uv_reprojected, velocity); + + // Add to the blend factor + blend_factor = clamp(blend_factor + factor_screen + factor_disocclusion, 0.0, 1.0); + } + + // Resolve + vec3 color_resolved = vec3(0.0); + { + // Tonemap + color_history = reinhard(color_history); + color_input = reinhard(color_input); + + // Reduce flickering + float lum_color = luminance(color_input); + float lum_history = luminance(color_history); + float diff = abs(lum_color - lum_history) / max(lum_color, max(lum_history, 1.001)); + diff = 1.0 - diff; + diff = diff * diff; + blend_factor = mix(0.0, blend_factor, diff); + + // Lerp/blend + color_resolved = mix(color_history, color_input, blend_factor); + + // Inverse tonemap + color_resolved = reinhard_inverse(color_resolved); + } + + return color_resolved; +} + +void main() { +#ifdef USE_SUBGROUPS + populate_group_shared_memory(gl_WorkGroupID.xy, gl_LocalInvocationIndex); +#endif + + // Out of bounds check + if (any(greaterThanEqual(vec2(gl_GlobalInvocationID.xy), params.resolution))) { + return; + } + +#ifdef USE_SUBGROUPS + const uvec2 pos_group = gl_LocalInvocationID.xy; + const uvec2 pos_group_top_left = gl_WorkGroupID.xy * kGroupSize - kBorderSize; +#else + const uvec2 pos_group = gl_GlobalInvocationID.xy; + const uvec2 pos_group_top_left = uvec2(0, 0); +#endif + const uvec2 pos_screen = gl_GlobalInvocationID.xy; + const vec2 uv = (gl_GlobalInvocationID.xy + 0.5f) / params.resolution; + + vec3 result = temporal_antialiasing(pos_group_top_left, pos_group, pos_screen, uv, history_buffer); + imageStore(output_buffer, ivec2(gl_GlobalInvocationID.xy), vec4(result, 1.0)); +} -- cgit v1.2.3