diff options
Diffstat (limited to 'source/blender/draw/engines/eevee_next/shaders/eevee_motion_blur_flatten_comp.glsl')
-rw-r--r-- | source/blender/draw/engines/eevee_next/shaders/eevee_motion_blur_flatten_comp.glsl | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/source/blender/draw/engines/eevee_next/shaders/eevee_motion_blur_flatten_comp.glsl b/source/blender/draw/engines/eevee_next/shaders/eevee_motion_blur_flatten_comp.glsl new file mode 100644 index 00000000000..cbbeea25d20 --- /dev/null +++ b/source/blender/draw/engines/eevee_next/shaders/eevee_motion_blur_flatten_comp.glsl @@ -0,0 +1,103 @@ + +/** + * Shaders that down-sample velocity buffer into squared tile of MB_TILE_DIVISOR pixels wide. + * Outputs the largest motion vector in the tile area. + * Also perform velocity resolve to speedup the convolution pass. + * + * Based on: + * A Fast and Stable Feature-Aware Motion Blur Filter + * by Jean-Philippe Guertin, Morgan McGuire, Derek Nowrouzezahrai + * + * Adapted from G3D Innovation Engine implementation. + */ + +#pragma BLENDER_REQUIRE(common_math_geom_lib.glsl) +#pragma BLENDER_REQUIRE(eevee_velocity_lib.glsl) + +shared uint payload_prev; +shared uint payload_next; +shared vec2 max_motion_prev; +shared vec2 max_motion_next; + +/* Store velocity magnitude in the MSB and thread id in the LSB. */ +uint pack_payload(vec2 motion, uvec2 thread_id) +{ + /* NOTE: We clamp max velocity to 16k pixels. */ + return (min(uint(ceil(length(motion))), 0xFFFFu) << 16u) | (thread_id.y << 8) | thread_id.x; +} + +/* Return thread index from the payload. */ +uvec2 unpack_payload(uint payload) +{ + return uvec2(payload & 0xFFu, (payload >> 8) & 0xFFu); +} + +void main() +{ + if (all(equal(gl_LocalInvocationID.xy, uvec2(0)))) { + payload_prev = 0u; + payload_next = 0u; + } + barrier(); + + uint local_payload_prev = 0u; + uint local_payload_next = 0u; + vec2 local_max_motion_prev; + vec2 local_max_motion_next; + + ivec2 texel = min(ivec2(gl_GlobalInvocationID.xy), imageSize(velocity_img) - 1); + + vec2 render_size = vec2(imageSize(velocity_img).xy); + vec2 uv = (vec2(texel) + 0.5) / render_size; + float depth = texelFetch(depth_tx, texel, 0).r; + vec4 motion = velocity_resolve(imageLoad(velocity_img, texel), uv, depth); +#ifdef FLATTEN_VIEWPORT + /* imageLoad does not perform the swizzling like sampler does. Do it manually. */ + motion = motion.xyxy; +#endif + + /* Store resolved velocity to speedup the gather pass. Out of bounds writes are ignored. + * Unfortunately, we cannot convert to pixel space here since it is also used by TAA and the + * motion blur needs to remain optional. */ + imageStore(velocity_img, ivec2(gl_GlobalInvocationID.xy), velocity_pack(motion)); + /* Clip velocity to viewport bounds (in NDC space). */ + vec2 line_clip; + line_clip.x = line_unit_square_intersect_dist_safe(uv * 2.0 - 1.0, motion.xy * 2.0); + line_clip.y = line_unit_square_intersect_dist_safe(uv * 2.0 - 1.0, -motion.zw * 2.0); + motion *= min(line_clip, vec2(1.0)).xxyy; + /* Convert to pixel space. Note this is only for velocity tiles. */ + motion *= render_size.xyxy; + /* Rescale to shutter relative motion for viewport. */ + motion *= motion_blur_buf.motion_scale.xxyy; + + uint sample_payload_prev = pack_payload(motion.xy, gl_LocalInvocationID.xy); + if (local_payload_prev < sample_payload_prev) { + local_payload_prev = sample_payload_prev; + local_max_motion_prev = motion.xy; + } + + uint sample_payload_next = pack_payload(motion.zw, gl_LocalInvocationID.xy); + if (local_payload_next < sample_payload_next) { + local_payload_next = sample_payload_next; + local_max_motion_next = motion.zw; + } + + /* Compare the local payload with the other threads. */ + atomicMax(payload_prev, local_payload_prev); + atomicMax(payload_next, local_payload_next); + barrier(); + + /* Need to broadcast the result to another thread in order to issue a unique write. */ + if (all(equal(unpack_payload(payload_prev), gl_LocalInvocationID.xy))) { + max_motion_prev = local_max_motion_prev; + } + if (all(equal(unpack_payload(payload_next), gl_LocalInvocationID.xy))) { + max_motion_next = local_max_motion_next; + } + barrier(); + + if (all(equal(gl_LocalInvocationID.xy, uvec2(0)))) { + ivec2 tile_co = ivec2(gl_WorkGroupID.xy); + imageStore(out_tiles_img, tile_co, vec4(max_motion_prev, max_motion_next)); + } +} |