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-rw-r--r--servers/visual/rasterizer_rd/shaders/ssao.glsl252
1 files changed, 0 insertions, 252 deletions
diff --git a/servers/visual/rasterizer_rd/shaders/ssao.glsl b/servers/visual/rasterizer_rd/shaders/ssao.glsl
deleted file mode 100644
index c9d7134610..0000000000
--- a/servers/visual/rasterizer_rd/shaders/ssao.glsl
+++ /dev/null
@@ -1,252 +0,0 @@
-/* clang-format off */
-[compute]
-
-#version 450
-
-VERSION_DEFINES
-
-layout(local_size_x = 8, local_size_y = 8, local_size_z = 1) in;
-/* clang-format on */
-
-#define TWO_PI 6.283185307179586476925286766559
-
-#ifdef SSAO_QUALITY_HIGH
-#define NUM_SAMPLES (20)
-#endif
-
-#ifdef SSAO_QUALITY_ULTRA
-#define NUM_SAMPLES (48)
-#endif
-
-#ifdef SSAO_QUALITY_LOW
-#define NUM_SAMPLES (8)
-#endif
-
-#if !defined(SSAO_QUALITY_LOW) && !defined(SSAO_QUALITY_HIGH) && !defined(SSAO_QUALITY_ULTRA)
-#define NUM_SAMPLES (12)
-#endif
-
-// If using depth mip levels, the log of the maximum pixel offset before we need to switch to a lower
-// miplevel to maintain reasonable spatial locality in the cache
-// If this number is too small (< 3), too many taps will land in the same pixel, and we'll get bad variance that manifests as flashing.
-// If it is too high (> 5), we'll get bad performance because we're not using the MIP levels effectively
-#define LOG_MAX_OFFSET (3)
-
-// This must be less than or equal to the MAX_MIP_LEVEL defined in SSAO.cpp
-#define MAX_MIP_LEVEL (4)
-
-// This is the number of turns around the circle that the spiral pattern makes. This should be prime to prevent
-// taps from lining up. This particular choice was tuned for NUM_SAMPLES == 9
-
-const int ROTATIONS[] = int[](
- 1, 1, 2, 3, 2, 5, 2, 3, 2,
- 3, 3, 5, 5, 3, 4, 7, 5, 5, 7,
- 9, 8, 5, 5, 7, 7, 7, 8, 5, 8,
- 11, 12, 7, 10, 13, 8, 11, 8, 7, 14,
- 11, 11, 13, 12, 13, 19, 17, 13, 11, 18,
- 19, 11, 11, 14, 17, 21, 15, 16, 17, 18,
- 13, 17, 11, 17, 19, 18, 25, 18, 19, 19,
- 29, 21, 19, 27, 31, 29, 21, 18, 17, 29,
- 31, 31, 23, 18, 25, 26, 25, 23, 19, 34,
- 19, 27, 21, 25, 39, 29, 17, 21, 27);
-/* clang-format on */
-
-//#define NUM_SPIRAL_TURNS (7)
-const int NUM_SPIRAL_TURNS = ROTATIONS[NUM_SAMPLES - 1];
-
-layout(set = 0, binding = 0) uniform sampler2D source_depth_mipmaps;
-layout(r8, set = 1, binding = 0) uniform restrict writeonly image2D dest_image;
-
-#ifndef USE_HALF_SIZE
-layout(set = 2, binding = 0) uniform sampler2D source_depth;
-#endif
-
-layout(set = 3, binding = 0) uniform sampler2D source_normal;
-
-layout(push_constant, binding = 1, std430) uniform Params {
- ivec2 screen_size;
- float z_far;
- float z_near;
-
- bool orthogonal;
- float intensity_div_r6;
- float radius;
- float bias;
-
- vec4 proj_info;
- vec2 pixel_size;
- float proj_scale;
- uint pad;
-}
-params;
-
-vec3 reconstructCSPosition(vec2 S, float z) {
- if (params.orthogonal) {
- return vec3((S.xy * params.proj_info.xy + params.proj_info.zw), z);
- } else {
- return vec3((S.xy * params.proj_info.xy + params.proj_info.zw) * z, z);
- }
-}
-
-vec3 getPosition(ivec2 ssP) {
- vec3 P;
-#ifdef USE_HALF_SIZE
- P.z = texelFetch(source_depth_mipmaps, ssP, 0).r;
- P.z = -P.z;
-#else
- P.z = texelFetch(source_depth, ssP, 0).r;
-
- P.z = P.z * 2.0 - 1.0;
- if (params.orthogonal) {
- P.z = ((P.z + (params.z_far + params.z_near) / (params.z_far - params.z_near)) * (params.z_far - params.z_near)) / 2.0;
- } else {
- P.z = 2.0 * params.z_near * params.z_far / (params.z_far + params.z_near - P.z * (params.z_far - params.z_near));
- }
- P.z = -P.z;
-#endif
- // Offset to pixel center
- P = reconstructCSPosition(vec2(ssP) + vec2(0.5), P.z);
- return P;
-}
-
-/** Returns a unit vector and a screen-space radius for the tap on a unit disk (the caller should scale by the actual disk radius) */
-vec2 tapLocation(int sampleNumber, float spinAngle, out float ssR) {
- // Radius relative to ssR
- float alpha = (float(sampleNumber) + 0.5) * (1.0 / float(NUM_SAMPLES));
- float angle = alpha * (float(NUM_SPIRAL_TURNS) * 6.28) + spinAngle;
-
- ssR = alpha;
- return vec2(cos(angle), sin(angle));
-}
-
-/** Read the camera-space position of the point at screen-space pixel ssP + unitOffset * ssR. Assumes length(unitOffset) == 1 */
-vec3 getOffsetPosition(ivec2 ssP, float ssR) {
- // Derivation:
- // mipLevel = floor(log(ssR / MAX_OFFSET));
-
- int mipLevel = clamp(int(floor(log2(ssR))) - LOG_MAX_OFFSET, 0, MAX_MIP_LEVEL);
-
- vec3 P;
-
- // We need to divide by 2^mipLevel to read the appropriately scaled coordinate from a MIP-map.
- // Manually clamp to the texture size because texelFetch bypasses the texture unit
- ivec2 mipP = clamp(ssP >> mipLevel, ivec2(0), (params.screen_size >> mipLevel) - ivec2(1));
-
-#ifdef USE_HALF_SIZE
- P.z = texelFetch(source_depth_mipmaps, mipP, mipLevel).r;
- P.z = -P.z;
-#else
- if (mipLevel < 1) {
- //read from depth buffer
- P.z = texelFetch(source_depth, mipP, 0).r;
- P.z = P.z * 2.0 - 1.0;
- if (params.orthogonal) {
- P.z = ((P.z + (params.z_far + params.z_near) / (params.z_far - params.z_near)) * (params.z_far - params.z_near)) / 2.0;
- } else {
- P.z = 2.0 * params.z_near * params.z_far / (params.z_far + params.z_near - P.z * (params.z_far - params.z_near));
- }
- P.z = -P.z;
-
- } else {
- //read from mipmaps
- P.z = texelFetch(source_depth_mipmaps, mipP, mipLevel - 1).r;
- P.z = -P.z;
- }
-#endif
-
- // Offset to pixel center
- P = reconstructCSPosition(vec2(ssP) + vec2(0.5), P.z);
-
- return P;
-}
-
-/** Compute the occlusion due to sample with index \a i about the pixel at \a ssC that corresponds
- to camera-space point \a C with unit normal \a n_C, using maximum screen-space sampling radius \a ssDiskRadius
-
- Note that units of H() in the HPG12 paper are meters, not
- unitless. The whole falloff/sampling function is therefore
- unitless. In this implementation, we factor out (9 / radius).
-
- Four versions of the falloff function are implemented below
-*/
-float sampleAO(in ivec2 ssC, in vec3 C, in vec3 n_C, in float ssDiskRadius, in float p_radius, in int tapIndex, in float randomPatternRotationAngle) {
- // Offset on the unit disk, spun for this pixel
- float ssR;
- vec2 unitOffset = tapLocation(tapIndex, randomPatternRotationAngle, ssR);
- ssR *= ssDiskRadius;
-
- ivec2 ssP = ivec2(ssR * unitOffset) + ssC;
-
- if (any(lessThan(ssP, ivec2(0))) || any(greaterThanEqual(ssP, params.screen_size))) {
- return 0.0;
- }
-
- // The occluding point in camera space
- vec3 Q = getOffsetPosition(ssP, ssR);
-
- vec3 v = Q - C;
-
- float vv = dot(v, v);
- float vn = dot(v, n_C);
-
- const float epsilon = 0.01;
- float radius2 = p_radius * p_radius;
-
- // A: From the HPG12 paper
- // Note large epsilon to avoid overdarkening within cracks
- //return float(vv < radius2) * max((vn - bias) / (epsilon + vv), 0.0) * radius2 * 0.6;
-
- // B: Smoother transition to zero (lowers contrast, smoothing out corners). [Recommended]
- float f = max(radius2 - vv, 0.0);
- return f * f * f * max((vn - params.bias) / (epsilon + vv), 0.0);
-
- // C: Medium contrast (which looks better at high radii), no division. Note that the
- // contribution still falls off with radius^2, but we've adjusted the rate in a way that is
- // more computationally efficient and happens to be aesthetically pleasing.
- // return 4.0 * max(1.0 - vv * invRadius2, 0.0) * max(vn - bias, 0.0);
-
- // D: Low contrast, no division operation
- // return 2.0 * float(vv < radius * radius) * max(vn - bias, 0.0);
-}
-
-void main() {
- // Pixel being shaded
- ivec2 ssC = ivec2(gl_GlobalInvocationID.xy);
- if (any(greaterThan(ssC, params.screen_size))) { //too large, do nothing
- return;
- }
-
- // World space point being shaded
- vec3 C = getPosition(ssC);
-
-#ifdef USE_HALF_SIZE
- vec3 n_C = texelFetch(source_normal, ssC << 1, 0).xyz * 2.0 - 1.0;
-#else
- vec3 n_C = texelFetch(source_normal, ssC, 0).xyz * 2.0 - 1.0;
-#endif
- n_C = normalize(n_C);
- n_C.y = -n_C.y; //because this code reads flipped
-
- // Hash function used in the HPG12 AlchemyAO paper
- float randomPatternRotationAngle = mod(float((3 * ssC.x ^ ssC.y + ssC.x * ssC.y) * 10), TWO_PI);
-
- // Reconstruct normals from positions. These will lead to 1-pixel black lines
- // at depth discontinuities, however the blur will wipe those out so they are not visible
- // in the final image.
-
- // Choose the screen-space sample radius
- // proportional to the projected area of the sphere
-
- float ssDiskRadius = -params.proj_scale * params.radius;
- if (!params.orthogonal) {
- ssDiskRadius = -params.proj_scale * params.radius / C.z;
- }
- float sum = 0.0;
- for (int i = 0; i < NUM_SAMPLES; ++i) {
- sum += sampleAO(ssC, C, n_C, ssDiskRadius, params.radius, i, randomPatternRotationAngle);
- }
-
- float A = max(0.0, 1.0 - sum * params.intensity_div_r6 * (5.0 / float(NUM_SAMPLES)));
-
- imageStore(dest_image, ssC, vec4(A));
-}