diff options
author | Clément Foucault <foucault.clem@gmail.com> | 2017-07-20 19:40:23 +0300 |
---|---|---|
committer | Clément Foucault <foucault.clem@gmail.com> | 2017-07-24 16:28:27 +0300 |
commit | f1bf9d6bfb9edf261586a3907d7197a805ce8c3b (patch) | |
tree | 845c757c881cfa95d4be0d2a6c1a9b4e3e19d07f /source/blender/draw/engines/eevee | |
parent | 09413fad12c92fcd6c3410eadcdfc8f91bc028ef (diff) |
Eevee: SSR: Add mipmap filtering and bias to reduce noise.
Also fix the roughness factors.
Diffstat (limited to 'source/blender/draw/engines/eevee')
6 files changed, 125 insertions, 25 deletions
diff --git a/source/blender/draw/engines/eevee/eevee_effects.c b/source/blender/draw/engines/eevee/eevee_effects.c index 6414ef8ff32..e4c4cb5d790 100644 --- a/source/blender/draw/engines/eevee/eevee_effects.c +++ b/source/blender/draw/engines/eevee/eevee_effects.c @@ -84,7 +84,10 @@ static struct { struct GPUShader *ssr_raytrace_sh; struct GPUShader *ssr_resolve_sh; + struct GPUShader *downsample_sh; + struct GPUTexture *depth_src; + struct GPUTexture *color_src; float pixelprojmat[4][4]; } e_data = {NULL}; /* Engine data */ @@ -99,6 +102,7 @@ extern char datatoc_effect_bloom_frag_glsl[]; extern char datatoc_effect_dof_vert_glsl[]; extern char datatoc_effect_dof_geom_glsl[]; extern char datatoc_effect_dof_frag_glsl[]; +extern char datatoc_effect_downsample_frag_glsl[]; extern char datatoc_lightprobe_lib_glsl[]; extern char datatoc_raytrace_lib_glsl[]; extern char datatoc_tonemap_frag_glsl[]; @@ -192,6 +196,8 @@ void EEVEE_effects_init(EEVEE_SceneLayerData *sldata, EEVEE_Data *vedata) MEM_freeN(ssr_shader_str); + e_data.downsample_sh = DRW_shader_create_fullscreen(datatoc_effect_downsample_frag_glsl, NULL); + e_data.volumetric_upsample_sh = DRW_shader_create_fullscreen(datatoc_volumetric_frag_glsl, "#define STEP_UPSAMPLE\n"); e_data.minmaxz_downlevel_sh = DRW_shader_create_fullscreen(datatoc_effect_minmaxz_frag_glsl, NULL); @@ -578,7 +584,7 @@ void EEVEE_effects_init(EEVEE_SceneLayerData *sldata, EEVEE_Data *vedata) /* Setup double buffer so we can access last frame as it was before post processes */ if ((effects->enabled_effects & EFFECT_DOUBLE_BUFFER) != 0) { - DRWFboTexture tex_double_buffer = {&txl->color_double_buffer, DRW_TEX_RGB_11_11_10, DRW_TEX_FILTER}; + DRWFboTexture tex_double_buffer = {&txl->color_double_buffer, DRW_TEX_RGB_11_11_10, DRW_TEX_FILTER | DRW_TEX_MIPMAP}; DRW_framebuffer_init(&fbl->double_buffer, &draw_engine_eevee_type, (int)viewport_size[0], (int)viewport_size[1], @@ -711,6 +717,13 @@ void EEVEE_effects_cache_init(EEVEE_SceneLayerData *sldata, EEVEE_Data *vedata) } { + psl->color_downsample_ps = DRW_pass_create("Downsample", DRW_STATE_WRITE_COLOR); + DRWShadingGroup *grp = DRW_shgroup_create(e_data.downsample_sh, psl->color_downsample_ps); + DRW_shgroup_uniform_buffer(grp, "source", &e_data.color_src); + DRW_shgroup_call_add(grp, quad, NULL); + } + + { psl->minmaxz_downlevel = DRW_pass_create("HiZ Down Level", DRW_STATE_WRITE_COLOR); DRWShadingGroup *grp = DRW_shgroup_create(e_data.minmaxz_downlevel_sh, psl->minmaxz_downlevel); DRW_shgroup_uniform_buffer(grp, "depthBuffer", &stl->g_data->minmaxz); @@ -833,6 +846,12 @@ static void minmax_downsample_cb(void *vedata, int UNUSED(level)) DRW_draw_pass(psl->minmaxz_downlevel); } +static void simple_downsample_cb(void *vedata, int UNUSED(level)) +{ + EEVEE_PassList *psl = ((EEVEE_Data *)vedata)->psl; + DRW_draw_pass(psl->color_downsample_ps); +} + void EEVEE_create_minmax_buffer(EEVEE_Data *vedata, GPUTexture *depth_src) { EEVEE_PassList *psl = vedata->psl; @@ -851,6 +870,17 @@ void EEVEE_create_minmax_buffer(EEVEE_Data *vedata, GPUTexture *depth_src) DRW_framebuffer_recursive_downsample(fbl->minmaxz_fb, stl->g_data->minmaxz, 6, &minmax_downsample_cb, vedata); } +/** + * Simple downsampling algorithm. Reconstruct mip chain up to mip level. + **/ +void EEVEE_downsample_buffer(EEVEE_Data *vedata, struct GPUFrameBuffer *fb_src, GPUTexture *texture_src, int level) +{ + e_data.color_src = texture_src; + + /* Create lower levels */ + DRW_framebuffer_recursive_downsample(fb_src, texture_src, level, &simple_downsample_cb, vedata); +} + void EEVEE_effects_do_volumetrics(EEVEE_SceneLayerData *sldata, EEVEE_Data *vedata) { EEVEE_PassList *psl = vedata->psl; @@ -902,6 +932,8 @@ void EEVEE_effects_do_ssr(EEVEE_SceneLayerData *UNUSED(sldata), EEVEE_Data *veda if ((effects->enabled_effects & EFFECT_SSR) != 0 && stl->g_data->valid_double_buffer) { DefaultTextureList *dtxl = DRW_viewport_texture_list_get(); + EEVEE_downsample_buffer(vedata, fbl->minmaxz_fb, txl->color_double_buffer, 5); + /* Raytrace at halfres. */ e_data.depth_src = dtxl->depth; // e_data.depth_src = stl->g_data->minmaxz; @@ -1078,6 +1110,7 @@ void EEVEE_draw_effects(EEVEE_Data *vedata) void EEVEE_effects_free(void) { + DRW_SHADER_FREE_SAFE(e_data.downsample_sh); DRW_SHADER_FREE_SAFE(e_data.ssr_raytrace_sh); DRW_SHADER_FREE_SAFE(e_data.ssr_resolve_sh); diff --git a/source/blender/draw/engines/eevee/eevee_engine.c b/source/blender/draw/engines/eevee/eevee_engine.c index 59f2613dd06..4ee3dee655f 100644 --- a/source/blender/draw/engines/eevee/eevee_engine.c +++ b/source/blender/draw/engines/eevee/eevee_engine.c @@ -56,7 +56,7 @@ static void EEVEE_engine_init(void *ved) stl->g_data->background_alpha = 1.0f; stl->g_data->valid_double_buffer = (txl->color_double_buffer != NULL); - DRWFboTexture tex = {&txl->color, DRW_TEX_RGB_11_11_10, DRW_TEX_FILTER}; + DRWFboTexture tex = {&txl->color, DRW_TEX_RGB_11_11_10, DRW_TEX_FILTER | DRW_TEX_MIPMAP}; const float *viewport_size = DRW_viewport_size_get(); DRW_framebuffer_init(&fbl->main, &draw_engine_eevee_type, diff --git a/source/blender/draw/engines/eevee/eevee_private.h b/source/blender/draw/engines/eevee/eevee_private.h index 015bc5b6a9e..f31f4f9fe6c 100644 --- a/source/blender/draw/engines/eevee/eevee_private.h +++ b/source/blender/draw/engines/eevee/eevee_private.h @@ -111,6 +111,7 @@ typedef struct EEVEE_PassList { struct DRWPass *volumetric_resolve_transmit_ps; struct DRWPass *ssr_raytrace; struct DRWPass *ssr_resolve; + struct DRWPass *color_downsample_ps; struct DRWPass *depth_pass; struct DRWPass *depth_pass_cull; @@ -504,6 +505,7 @@ void EEVEE_lightprobes_free(void); void EEVEE_effects_init(EEVEE_SceneLayerData *sldata, EEVEE_Data *vedata); void EEVEE_effects_cache_init(EEVEE_SceneLayerData *sldata, EEVEE_Data *vedata); void EEVEE_create_minmax_buffer(EEVEE_Data *vedata, struct GPUTexture *depth_src); +void EEVEE_downsample_buffer(EEVEE_Data *vedata, struct GPUFrameBuffer *fb_src, struct GPUTexture *texture_src, int level); void EEVEE_effects_do_volumetrics(EEVEE_SceneLayerData *sldata, EEVEE_Data *vedata); void EEVEE_effects_do_ssr(EEVEE_SceneLayerData *sldata, EEVEE_Data *vedata); void EEVEE_draw_effects(EEVEE_Data *vedata); diff --git a/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl b/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl index 059f0598156..e6cbcde77c7 100644 --- a/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl +++ b/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl @@ -374,6 +374,22 @@ void accumulate_light(vec3 light, float fac, inout vec4 accum) accum += vec4(light, 1.0) * min(fac, (1.0 - accum.a)); } +/* ----------- Cone Apperture Approximation --------- */ + +/* Return a fitted cone angle given the input roughness */ +float cone_cosine(float r) +{ + /* Using phong gloss + * roughness = sqrt(2/(gloss+2)) */ + float gloss = -2 + 2 / (r * r); + /* Drobot 2014 in GPUPro5 */ + // return cos(2.0 * sqrt(2.0 / (gloss + 2))); + /* Uludag 2014 in GPUPro5 */ + // return pow(0.244, 1 / (gloss + 1)); + /* Jimenez 2016 in Practical Realtime Strategies for Accurate Indirect Occlusion*/ + return exp2(-3.32193 * r * r); +} + /* --------- Closure ---------- */ #ifdef VOLUMETRICS diff --git a/source/blender/draw/engines/eevee/shaders/effect_downsample_frag.glsl b/source/blender/draw/engines/eevee/shaders/effect_downsample_frag.glsl new file mode 100644 index 00000000000..4a79fa908b1 --- /dev/null +++ b/source/blender/draw/engines/eevee/shaders/effect_downsample_frag.glsl @@ -0,0 +1,15 @@ +/** + * Simple downsample shader. Takes the average of the 4 texels of lower mip. + **/ + +uniform sampler2D source; + +out vec4 FragColor; + +void main() +{ + /* Reconstructing Target uvs like this avoid missing pixels if NPO2 */ + vec2 uvs = gl_FragCoord.xy * 2.0 / vec2(textureSize(source, 0)); + + FragColor = texture(source, uvs); +}
\ No newline at end of file diff --git a/source/blender/draw/engines/eevee/shaders/effect_ssr_frag.glsl b/source/blender/draw/engines/eevee/shaders/effect_ssr_frag.glsl index 7337ec792c9..4a1cea1338e 100644 --- a/source/blender/draw/engines/eevee/shaders/effect_ssr_frag.glsl +++ b/source/blender/draw/engines/eevee/shaders/effect_ssr_frag.glsl @@ -4,17 +4,25 @@ uniform sampler2DArray utilTex; #endif /* UTIL_TEX */ -vec3 generate_ray(ivec2 pix, vec3 V, vec3 N, float roughnessSquared, out float pdf) +#define BRDF_BIAS 0.7 + +vec3 generate_ray(ivec2 pix, vec3 V, vec3 N, float a2, out float pdf) { float NH; vec3 T, B; make_orthonormal_basis(N, T, B); /* Generate tangent space */ vec3 rand = texelFetch(utilTex, ivec3(pix % LUT_SIZE, 2), 0).rba; - vec3 H = sample_ggx(rand, roughnessSquared, N, T, B, NH); /* Microfacet normal */ - pdf = max(32e32, pdf_ggx_reflect(NH, roughnessSquared)); /* Theoretical limit of 10bit float (not in practice?) */ + + /* Importance sampling bias */ + rand.x = mix(rand.x, 0.0, BRDF_BIAS); + + vec3 H = sample_ggx(rand, a2, N, T, B, NH); /* Microfacet normal */ + pdf = min(1024e32, pdf_ggx_reflect(NH, a2)); /* Theoretical limit of 16bit float */ return reflect(-V, H); } +#define MAX_MIP 5.0 + #ifdef STEP_RAYTRACE uniform sampler2D depthBuffer; @@ -44,11 +52,12 @@ void main() /* Retrieve pixel data */ vec4 speccol_roughness = texelFetch(specroughBuffer, fullres_texel, 0).rgba; float roughness = speccol_roughness.a; - float roughnessSquared = roughness * roughness; + float roughnessSquared = max(1e-3, roughness * roughness); + float a2 = roughnessSquared * roughnessSquared; /* Generate Ray */ float pdf; - vec3 R = generate_ray(halfres_texel, V, N, roughnessSquared, pdf); + vec3 R = generate_ray(halfres_texel, V, N, a2, pdf); /* Search for the planar reflection affecting this pixel */ /* If no planar is found, fallback to screen space */ @@ -65,7 +74,11 @@ void main() //float hit_dist = raycast(depthBuffer, W, R); /* Raycast over screen */ - float hit_dist = raycast(depthBuffer, viewPosition, R); + float hit_dist = -1.0; + if (dot(R, N) > 0.0001) { + /* Only raytrace if ray is above the surface normal */ + hit_dist = raycast(depthBuffer, viewPosition, R); + } vec2 hit_co = project_point(ProjectionMatrix, viewPosition + R * hit_dist).xy * 0.5 + 0.5; @@ -164,7 +177,7 @@ float screen_border_mask(vec2 past_hit_co, vec3 hit) hit_co.zw = past_hit_co; const float margin = 0.002; - const float atten = 0.05 + margin; /* Screen percentage */ + const float atten = 0.1 + margin; /* Screen percentage */ hit_co = smoothstep(margin, atten, hit_co) * (1 - smoothstep(1.0 - atten, 1.0 - margin, hit_co)); vec2 atten_fac = min(hit_co.xy, hit_co.zw); @@ -179,7 +192,9 @@ void main() { ivec2 halfres_texel = ivec2(gl_FragCoord.xy / 2.0); ivec2 fullres_texel = ivec2(gl_FragCoord.xy); - vec2 uvs = gl_FragCoord.xy / vec2(textureSize(depthBuffer, 0)); + vec2 texture_size = vec2(textureSize(depthBuffer, 0)); + vec2 uvs = gl_FragCoord.xy / texture_size; + vec3 rand = texelFetch(utilTex, ivec3(fullres_texel % LUT_SIZE, 2), 0).rba; float depth = textureLod(depthBuffer, uvs, 0.0).r; @@ -194,48 +209,67 @@ void main() vec3 N = mat3(ViewMatrixInverse) * normal_decode(texelFetch(normalBuffer, fullres_texel, 0).rg, viewCameraVec); vec4 speccol_roughness = texelFetch(specroughBuffer, fullres_texel, 0).rgba; float roughness = speccol_roughness.a; - float roughnessSquared = roughness * roughness; + float roughnessSquared = max(1e-3, roughness * roughness); vec4 spec_accum = vec4(0.0); - /* Resolve SSR and compute contribution */ + /* Resolve SSR */ + float cone_cos = cone_cosine(roughness); + float cone_tan = sqrt(1 - cone_cos * cone_cos) / cone_cos; + cone_tan *= mix(saturate(dot(N, V) * 2.0), 1.0, sqrt(roughness)); /* Elongation fit */ - /* We generate the same rays that has been generated in the raycast step. - * But we add this ray from our resolve pixel position, increassing accuracy. */ vec3 ssr_accum = vec3(0.0); float weight_acc = 0.0; - float mask = 0.0; - const ivec2 neighbors[7] = ivec2[7](ivec2(0, 0), ivec2(2, 1), ivec2(-2, 1), ivec2(0, -2), ivec2(-2, -1), ivec2(2, -1), ivec2(0, 2)); - int invert_neighbor = ((((fullres_texel.x & 0x1) + (fullres_texel.y & 0x1)) & 0x1) == 0) ? 1 : -1; + float mask_acc = 0.0; + float dist_acc = 0.0; + float hit_acc = 0.0; + const ivec2 neighbors[4] = ivec2[4](ivec2(0, 0), ivec2(1, 1), ivec2(0, 1), ivec2(1, 0)); + ivec2 invert_neighbor; + invert_neighbor.x = ((fullres_texel.x & 0x1) == 0) ? 1 : -1; + invert_neighbor.y = ((fullres_texel.y & 0x1) == 0) ? 1 : -1; for (int i = 0; i < NUM_NEIGHBORS; i++) { ivec2 target_texel = halfres_texel + neighbors[i] * invert_neighbor; float pdf = texelFetch(pdfBuffer, target_texel, 0).r; /* Check if there was a hit */ - if (pdf != 0.0) { + if (pdf > 0.001) { vec2 hit_co = texelFetch(hitBuffer, target_texel, 0).rg; /* Reconstruct ray */ float hit_depth = textureLod(depthBuffer, hit_co, 0.0).r; vec3 hit_pos = get_world_space_from_depth(hit_co, hit_depth); + /* Evaluate BSDF */ + vec3 L = normalize(hit_pos - worldPosition); + float bsdf = bsdf_ggx(N, L, V, roughnessSquared); + /* Find hit position in previous frame */ vec2 ref_uvs = get_reprojected_reflection(hit_pos, worldPosition, N); + vec2 source_uvs = project_point(PastViewProjectionMatrix, worldPosition).xy * 0.5 + 0.5; - /* Evaluate BSDF */ - vec3 L = normalize(hit_pos - worldPosition); - float bsdf = bsdf_ggx(N, L, V, max(1e-3, roughness)); + /* Estimate a cone footprint to sample a corresponding mipmap level */ + /* compute cone footprint Using UV distance because we are using screen space filtering */ + float cone_footprint = cone_tan * distance(ref_uvs, source_uvs); + float mip = BRDF_BIAS * clamp(log2(cone_footprint * max(texture_size.x, texture_size.y)), 0.0, MAX_MIP); - float weight = bsdf / max(1e-8, pdf); - mask += screen_border_mask(ref_uvs, hit_pos); - ssr_accum += textureLod(colorBuffer, ref_uvs, 0.0).rgb * weight; + float border_mask = screen_border_mask(ref_uvs, hit_pos); + float weight = border_mask * bsdf / max(1e-8, pdf); + ssr_accum += textureLod(colorBuffer, ref_uvs, mip).rgb * weight; weight_acc += weight; + dist_acc += distance(hit_pos, worldPosition); + mask_acc += border_mask; + hit_acc += 1.0; } } + /* Compute SSR contribution */ if (weight_acc > 0.0) { - accumulate_light(ssr_accum / weight_acc, mask / float(NUM_NEIGHBORS), spec_accum); + /* Fade intensity based on roughness and average distance to hit */ + float fade = saturate(2.0 - roughness * 2.0); /* fade between 0.5 and 1.0 roughness */ + fade *= mask_acc / hit_acc; + fade *= mask_acc / hit_acc; + accumulate_light(ssr_accum / weight_acc, fade, spec_accum); } /* If SSR contribution is not 1.0, blend with cubemaps */ |