diff options
Diffstat (limited to 'servers/visual/rasterizer_rd/shaders/ssao.glsl')
-rw-r--r-- | servers/visual/rasterizer_rd/shaders/ssao.glsl | 252 |
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)); -} |