diff options
Diffstat (limited to 'source/blender/gpu/shaders/gpu_shader_material_utils.glsl')
| -rw-r--r-- | source/blender/gpu/shaders/gpu_shader_material_utils.glsl | 147 |
1 files changed, 90 insertions, 57 deletions
diff --git a/source/blender/gpu/shaders/gpu_shader_material_utils.glsl b/source/blender/gpu/shaders/gpu_shader_material_utils.glsl index ea1dc03d467..b7868a77434 100644 --- a/source/blender/gpu/shaders/gpu_shader_material_utils.glsl +++ b/source/blender/gpu/shaders/gpu_shader_material_utils.glsl @@ -174,9 +174,9 @@ float linear_depth(float z) } } -float backface_depth(ivec2 texelpos) +float backface_depth(ivec2 texelpos, int lod) { - float depth = linear_depth(texelFetch(unfbackfacebuf, texelpos, 0).r); + float depth = linear_depth(texelFetch(unfbackfacebuf, texelpos, lod).r); /* background case */ if (depth == 1.0) @@ -185,9 +185,9 @@ float backface_depth(ivec2 texelpos) return -depth; } -float frontface_depth(ivec2 texelpos) +float frontface_depth(ivec2 texelpos, int lod) { - float depth = linear_depth(texelFetch(unfdepthbuf, texelpos, 0).r); + float depth = linear_depth(texelFetch(unfdepthbuf, texelpos, lod).r); /* background case */ if (depth == 1.0) @@ -907,93 +907,126 @@ bool raycast(vec3 ray_origin, vec3 ray_dir, float jitter, out float hitstep, out P0 = P0.yx; } - /* Track the derivatives */ - float step_sign = sign(delta.x); - float invdx = step_sign / delta.x; - vec2 dP = vec2(step_sign, invdx * delta.y); - vec3 dQ = (Q1 - Q0) * invdx; - float dk = (k1 - k0) * invdx; + /* Track the derivatives */ + float step_sign = sign(delta.x); + float invdx = step_sign / delta.x; + vec2 dP = vec2(step_sign, invdx * delta.y); + vec3 dQ = (Q1 - Q0) * invdx; + float dk = (k1 - k0) * invdx; - /* Stride */ - float stride = 1.0; - - /* Calculate pixel stride based on distance of ray origin from camera. */ - //float stride_scale = 1.0 - min( 1.0, -ray_origin.z); - //stride = 1.0 + stride_scale * stride; + /* Slide each value from the start of the ray to the end */ + vec4 pqk = vec4(P0, Q0.z, k0); - /* Scale derivatives by the desired pixel stride */ - dP *= stride; dQ *= stride; dk *= stride; + /* Scale derivatives by the desired pixel stride */ + vec4 dPQK = vec4(dP, dQ.z, dk) * 1.0; - /* Offset the starting values by the jitter fraction */ - //P0 += dP * jitter; Q0 += dQ * jitter; k0 += dk * jitter; + bool hit = false; - /* Slide each value from the start of the ray to the end */ - vec3 Q = Q0; vec2 P = P0; float k = k0; +#if 1 /* Linear 2D raymarching */ /* We track the ray depth at +/- 1/2 pixel to treat pixels as clip-space solid * voxels. Because the depth at -1/2 for a given pixel will be the same as at * +1/2 for the previous iteration, we actually only have to compute one value * per iteration. */ float prev_zmax = ray_origin.z; - float zmax, zmin; + float zmax, zmin; - /* P1.x is never modified after this point, so pre-scale it by - * the step direction for a signed comparison */ - float end = P1.x * step_sign; + /* P1.x is never modified after this point, so pre-scale it by + * the step direction for a signed comparison */ + float end = P1.x * step_sign; - bool hit = false; for (hitstep = 0.0; hitstep < unfssrparam.x && !hit; hitstep++) { /* Ray finished & no hit*/ - if ((P.x * step_sign) > end) break; + if ((pqk.x * step_sign) > end) break; - P += dP; Q.z += dQ.z; k += dk; + /* step through current cell */ + pqk += dPQK; - hitpixel = permute ? P.yx : P; + hitpixel = permute ? pqk.yx : pqk.xy; zmin = prev_zmax; - zmax = (dQ.z * 0.5 + Q.z) / (dk * 0.5 + k); + zmax = (dPQK.z * 0.5 + pqk.z) / (dPQK.w * 0.5 + pqk.w); prev_zmax = zmax; swapIfBigger(zmin, zmax); - float frontface = frontface_depth(ivec2(hitpixel)); + float frontface = frontface_depth(ivec2(hitpixel), 0); if (zmax < frontface) { + /* Below surface */ #ifdef USE_BACKFACE - float backface = backface_depth(ivec2(hitpixel)); + float backface = backface_depth(ivec2(hitpixel), 0); #else - float backface = frontface - 1.0; /* Todo find a good thickness */ + float backface = frontface - 0.2; /* Todo find a good thickness */ #endif - hit = (zmin > backface); + hit = (zmax > backface); } } - hitco = (Q0 + dQ * hitstep) / k; - return hit; -} + /* Hit coordinate in 3D */ + hitco = (Q0 + dQ * hitstep) / pqk.w; + +#else /* Hierarchical raymarching */ + + float z, mip, mippow, s; + float level = 1.0; + float steps = 0.0; + float dir = 1.0; + float lastdir = 1.0; + for (hitstep = 0.0; hitstep < unfssrparam.x && level > 0.0; hitstep++) { + mip = level - 1.0; + mippow = pow(2, mip); -#if 0 -/* 3D raycast */ -bool hierarchical_raycast(vec3 ray_origin, vec3 ray_dir, float jitter, out float hitstep, out vec2 hitpixel, out vec3 hitco) -{ - /* ssr_parameters */ - ray_dir *= unfssrparam.y; /* step between samples */ - - hitco = ray_origin; - hitco += ray_dir * jitter; - - hitpixel = vec2(0.0); - float mip = 0.0; - for (hitstep = 0.0; hitstep < unfssrparam.x; hitstep++) { /* step through current cell */ - if (above) mip++; - if (below) mip--; + //s = dir * max(1.0, mippow / 2); + s = dir * mippow; + //s = dir * level; + P += dP * s; Q.z += dQ.z * s; k += dk * s; steps += s; + + hitpixel = permute ? P.yx : P; + z = dQ.z / k; + + float frontface = frontface_depth(ivec2(hitpixel / mippow), int(mip)); + + if (z < frontface) { + /* Below surface */ +#ifdef USE_BACKFACE + float backface = backface_depth(ivec2(hitpixel), 0); +#else + float backface = -1e16; /* Todo find a good thickness */ +#endif + if (z > backface) { + /* Hit */ + /* This will step back the current step */ + //s = -1.0 * level; + //P += dP * s; Q.z += dQ.z * s; k += dk * s; steps += s; + dir = -1.0; + level--; + continue; + } + } + + /* Above surface */ + if (dir != -1.0 && lastdir != -1.0) { + /* Only step up in mip if the last iteration was positive + * This way we don't skip potential occluders */ + level++; + level = min(level, 5.0); + } + lastdir = dir; + dir = 1.0; } - /* No hit */ - return false; -} + hitstep = 1.0; + + hit = (level == 0.0); + + /* Hit coordinate in 3D */ + hitco = (Q0 + dQ * steps) / k; #endif + return hit; +} + float ssr_contribution(vec3 ray_origin, float hitstep, bool hit, inout vec3 hitco) { /* ssr_parameters */ @@ -1010,5 +1043,5 @@ float ssr_contribution(vec3 ray_origin, float hitstep, bool hit, inout vec3 hitc float maxdimension = saturate(max(abs(co.x), abs(co.y))); float screenfade = saturate((0.999999 - maxdimension) * attenuation); - return sqrt(stepfade * screenfade) * float(hit); + return smoothstep(0.0, 1.0, stepfade * screenfade) * float(hit); } |