[2884] | 1 | #include "../shaderenv.h"
|
---|
| 2 |
|
---|
[2881] | 3 | ////////////////////
|
---|
| 4 | // Screen Spaced Ambient Occlusion shader
|
---|
| 5 | // based on shader of Alexander Kusternig
|
---|
| 6 |
|
---|
| 7 |
|
---|
| 8 | struct fragment
|
---|
| 9 | {
|
---|
| 10 | // normalized screen position
|
---|
| 11 | float4 pos: WPOS;
|
---|
[2889] | 12 | float2 texCoord: TEXCOORD0;
|
---|
| 13 | float3 view: TEXCOORD1;
|
---|
[2881] | 14 | };
|
---|
| 15 |
|
---|
| 16 |
|
---|
| 17 | struct pixel
|
---|
| 18 | {
|
---|
| 19 | float4 illum_col: COLOR0;
|
---|
| 20 | };
|
---|
| 21 |
|
---|
| 22 |
|
---|
[2990] | 23 | inline float2 myreflect(float2 pt, float2 n)
|
---|
[2881] | 24 | {
|
---|
| 25 | // distance to plane
|
---|
| 26 | float d = dot(n, pt);
|
---|
| 27 | // reflect around plane
|
---|
| 28 | float2 rpt = pt - d * 2.0f * n;
|
---|
[2886] | 29 |
|
---|
[2881] | 30 | return rpt;
|
---|
| 31 | }
|
---|
| 32 |
|
---|
| 33 |
|
---|
[2990] | 34 | inline float3 Interpol(float2 w, float3 bl, float3 br, float3 tl, float3 tr)
|
---|
[2986] | 35 | {
|
---|
[2991] | 36 | float3 x1 = lerp(bl, tl, w.y);
|
---|
| 37 | float3 x2 = lerp(br, tr, w.y);
|
---|
| 38 | float3 v = lerp(x1, x2, w.x);
|
---|
[2987] | 39 |
|
---|
| 40 | return v;
|
---|
| 41 | }
|
---|
| 42 |
|
---|
[2988] | 43 |
|
---|
[2991] | 44 | inline float3 ReconstructSamplePosition(float3 eyePos,
|
---|
| 45 | uniform sampler2D colors,
|
---|
| 46 | float2 texcoord,
|
---|
| 47 | float3 bl, float3 br, float3 tl, float3 tr)
|
---|
[2988] | 48 | {
|
---|
[2990] | 49 | /*float eyeSpaceDepth = tex2Dlod(colors, float4(texcoord, 0, SSAO_MIPMAP_LEVEL)).w;
|
---|
| 50 |
|
---|
| 51 | // reconstruct world space position
|
---|
| 52 | float3 rotView = normalize(Interpol(texcoord, bl, br, tl, tr));
|
---|
[2991] | 53 | float3 sample_position = eyePos - rotView * eyeSpaceDepth;*/
|
---|
[2990] | 54 | float3 sample_position = tex2Dlod(colors, float4(texcoord, 0, SSAO_MIPMAP_LEVEL)).xyz;
|
---|
[2988] | 55 |
|
---|
[2990] | 56 | return sample_position;
|
---|
[2988] | 57 | }
|
---|
| 58 |
|
---|
| 59 |
|
---|
[2881] | 60 | /** The ssao shader returning the an intensity value between 0 and 1
|
---|
| 61 | */
|
---|
[2904] | 62 | float2 ssao(fragment IN,
|
---|
[2985] | 63 | uniform sampler2D colors,
|
---|
[2881] | 64 | uniform sampler2D noiseTexture,
|
---|
| 65 | uniform float2 samples[NUM_SAMPLES],
|
---|
| 66 | uniform float3 currentNormal,
|
---|
[2974] | 67 | uniform float4 centerPosition,
|
---|
[2985] | 68 | uniform float scaleFactor,
|
---|
[2990] | 69 | //uniform float3 viewDir,
|
---|
[2986] | 70 | uniform float3 eyePos,
|
---|
| 71 | uniform float3 bl,
|
---|
| 72 | uniform float3 br,
|
---|
| 73 | uniform float3 tl,
|
---|
[2988] | 74 | uniform float3 tr
|
---|
[2881] | 75 | )
|
---|
| 76 | {
|
---|
| 77 | // Check in a circular area around the current position.
|
---|
| 78 | // Shoot vectors to the positions there, and check the angle to these positions.
|
---|
| 79 | // Summing up these angles gives an estimation of the occlusion at the current position.
|
---|
| 80 |
|
---|
| 81 | float total_ao = 0.0;
|
---|
[2904] | 82 | float numSamples = 0;
|
---|
[2881] | 83 |
|
---|
[2986] | 84 |
|
---|
[2881] | 85 | for (int i = 0; i < NUM_SAMPLES; ++ i)
|
---|
| 86 | {
|
---|
[2892] | 87 | const float2 offset = samples[i];
|
---|
[2881] | 88 |
|
---|
[2903] | 89 | #if 1
|
---|
[2881] | 90 | ////////////////////
|
---|
[2903] | 91 | // add random noise: reflect around random normal vector (warning: slow!)
|
---|
[2985] | 92 |
|
---|
[2903] | 93 | float2 mynoise = tex2D(noiseTexture, IN.texCoord.xy).xy;
|
---|
[2892] | 94 | const float2 offsetTransformed = myreflect(offset, mynoise);
|
---|
[2903] | 95 | #else
|
---|
| 96 | const float2 offsetTransformed = offset;
|
---|
| 97 | #endif
|
---|
[2881] | 98 | // weight with projected coordinate to reach similar kernel size for near and far
|
---|
[2974] | 99 | float2 texcoord = IN.texCoord.xy + offsetTransformed * AREA_SIZE * scaleFactor;
|
---|
[2881] | 100 |
|
---|
[2904] | 101 | if ((texcoord.x <= 1.0f) && (texcoord.x >= 0.0f) && (texcoord.y <= 1.0f) && (texcoord.y >= 0.0f))
|
---|
| 102 | ++ numSamples;
|
---|
| 103 |
|
---|
[2991] | 104 | float3 sample_position = ReconstructSamplePosition(eyePos, colors, texcoord, bl, br, tl, tr);
|
---|
[2989] | 105 |
|
---|
[2881] | 106 | float3 vector_to_sample = sample_position - centerPosition.xyz;
|
---|
| 107 | const float length_to_sample = length(vector_to_sample);
|
---|
| 108 |
|
---|
| 109 | float3 direction_to_sample = vector_to_sample / length_to_sample;
|
---|
| 110 |
|
---|
[2885] | 111 | // angle between current normal and direction to sample controls AO intensity.
|
---|
[2881] | 112 | const float cos_angle = max(dot(direction_to_sample, currentNormal), 0.0f);
|
---|
| 113 |
|
---|
[2979] | 114 | // the distance_scale offset is used to avoid singularity that occurs at global illumination when
|
---|
| 115 | // the distance to a sample approaches zero
|
---|
[2881] | 116 | const float distance_intensity =
|
---|
| 117 | (SAMPLE_INTENSITY * DISTANCE_SCALE) / (DISTANCE_SCALE + length_to_sample * length_to_sample);
|
---|
| 118 |
|
---|
[2911] | 119 | #if 0
|
---|
[2885] | 120 | // if surface normal perpenticular to view dir, approx. half of the samples will not count
|
---|
| 121 | // => compensate for this (on the other hand, projected sampling area could be larger!)
|
---|
[2911] | 122 | const float view_correction = 1.0f + VIEW_CORRECTION_SCALE * (1.0f - dot(currentViewDir, currentNormal));
|
---|
| 123 | total_ao += cos_angle * distance_intensity * view_correction;
|
---|
| 124 | #endif
|
---|
[2887] | 125 | total_ao += cos_angle * distance_intensity;
|
---|
[2881] | 126 | }
|
---|
| 127 |
|
---|
[2904] | 128 | return float2(max(0.0f, 1.0f - total_ao), numSamples);
|
---|
[2890] | 129 | //return saturate(dot(currentViewDir, currentNormal));
|
---|
[2881] | 130 | }
|
---|
| 131 |
|
---|
| 132 |
|
---|
| 133 | /** The mrt shader for screen space ambient occlusion
|
---|
| 134 | */
|
---|
| 135 | pixel main(fragment IN,
|
---|
| 136 | uniform sampler2D colors,
|
---|
| 137 | uniform sampler2D positions,
|
---|
| 138 | uniform sampler2D normals,
|
---|
| 139 | uniform sampler2D noiseTexture,
|
---|
| 140 | uniform float2 samples[NUM_SAMPLES],
|
---|
| 141 | uniform sampler2D oldTex,
|
---|
| 142 | const uniform float4x4 oldModelViewProj,
|
---|
| 143 | uniform float maxDepth,
|
---|
[2985] | 144 | uniform float temporalCoherence,
|
---|
[2986] | 145 | uniform float3 eyePos,
|
---|
| 146 | uniform float3 bl,
|
---|
| 147 | uniform float3 br,
|
---|
| 148 | uniform float3 tl,
|
---|
| 149 | uniform float3 tr
|
---|
[2881] | 150 | )
|
---|
| 151 | {
|
---|
| 152 | pixel OUT;
|
---|
| 153 |
|
---|
| 154 | float4 norm = tex2D(normals, IN.texCoord.xy);
|
---|
| 155 | float3 normal = normalize(norm.xyz);
|
---|
[2975] | 156 |
|
---|
[2974] | 157 | // a constant ambient term
|
---|
| 158 | const float amb = norm.w;
|
---|
| 159 | // the w coordinate from the persp. projection
|
---|
| 160 | float w = norm.w;
|
---|
[2881] | 161 | // the current world position
|
---|
| 162 | const float4 centerPosition = tex2D(positions, IN.texCoord.xy);
|
---|
[2990] | 163 |
|
---|
| 164 | /*
|
---|
[2989] | 165 | /// the current view direction
|
---|
| 166 | float3 viewDir = normalize(IN.view);
|
---|
[2990] | 167 | const float eyeDepth = tex2D(colors, IN.texCoord.xy).w;
|
---|
[2988] | 168 | float4 centerPosition2;
|
---|
| 169 | centerPosition2.xyz = eyePos - view2 * eyeDepth;
|
---|
[2989] | 170 | */
|
---|
| 171 |
|
---|
[2988] | 172 | // the current depth
|
---|
[2974] | 173 | const float currentDepth = centerPosition.w;
|
---|
[2881] | 174 |
|
---|
[2986] | 175 | //const float2 ao = ssao(IN, positions, noiseTexture, samples, normal, centerPosition, w, viewDir, eyePos);
|
---|
[2991] | 176 | const float2 ao = ssao(IN, positions, noiseTexture, samples, normal, centerPosition, w, eyePos, bl, br, tl, tr);
|
---|
[2881] | 177 |
|
---|
| 178 |
|
---|
| 179 | /////////////////
|
---|
| 180 | //-- compute temporally smoothing
|
---|
| 181 |
|
---|
| 182 | float4 realPos = centerPosition * maxDepth;
|
---|
| 183 | realPos.w = 1.0f;
|
---|
| 184 |
|
---|
[2975] | 185 |
|
---|
| 186 | ///////////
|
---|
| 187 | //-- reprojection from new frame into old one
|
---|
| 188 |
|
---|
[2881] | 189 | float4 oldPos = mul(oldModelViewProj, realPos);
|
---|
| 190 |
|
---|
| 191 | const float newDepth = oldPos.z / oldPos.w;
|
---|
| 192 |
|
---|
| 193 | float2 tex = (oldPos.xy / oldPos.w) * 0.5f + 0.5f;
|
---|
| 194 | float4 oldCol = tex2D(oldTex, tex);
|
---|
| 195 |
|
---|
| 196 | const float oldDepth = oldCol.w;
|
---|
| 197 | const float depthDif = 1.0f - newDepth / oldDepth;
|
---|
| 198 |
|
---|
[2897] | 199 | float oldWeight = clamp(oldCol.z, 0, temporalCoherence);
|
---|
[2904] | 200 | float oldNumSamples = oldCol.y;
|
---|
| 201 |
|
---|
[2897] | 202 | float newWeight;
|
---|
[2881] | 203 |
|
---|
[2982] | 204 | float newNumSamples = ao.y;
|
---|
| 205 |
|
---|
[2904] | 206 | if (//(temporalCoherence > 0) &&
|
---|
[2897] | 207 | (tex.x >= 0.0f) && (tex.x < 1.0f) &&
|
---|
[2881] | 208 | (tex.y >= 0.0f) && (tex.y < 1.0f) &&
|
---|
[2982] | 209 | (abs(depthDif) < 1e-4f)
|
---|
[2991] | 210 | // if visibility changed in the surrounding area we have to recompute
|
---|
| 211 | && (oldNumSamples > 0.8f * newNumSamples)
|
---|
[2982] | 212 | //&& (oldAvgDepth / newAvgDepth > 0.99)
|
---|
[2904] | 213 | )
|
---|
[2881] | 214 | {
|
---|
[2904] | 215 | // increase the weight for convergence
|
---|
| 216 | newWeight = oldWeight + 1.0f;
|
---|
| 217 | OUT.illum_col.xy = (ao.xy + oldCol.xy * oldWeight) / newWeight;
|
---|
| 218 |
|
---|
| 219 | //if (!(oldNumSamples > ao.y - 1.5f)) newWeight = 0;
|
---|
[2881] | 220 | }
|
---|
| 221 | else
|
---|
[2982] | 222 | {
|
---|
[2904] | 223 | OUT.illum_col.xy = ao.xy;
|
---|
[2897] | 224 | newWeight = 0;
|
---|
[2881] | 225 | }
|
---|
| 226 |
|
---|
[2897] | 227 | OUT.illum_col.z = newWeight;
|
---|
[2880] | 228 | OUT.illum_col.w = currentDepth;
|
---|
| 229 |
|
---|
[2881] | 230 | return OUT;
|
---|
| 231 | }
|
---|
[2880] | 232 |
|
---|
[2881] | 233 |
|
---|
[2880] | 234 | pixel combine(fragment IN,
|
---|
| 235 | uniform sampler2D colors,
|
---|
[2974] | 236 | uniform sampler2D ssaoTex,
|
---|
| 237 | uniform sampler2D positions)
|
---|
[2880] | 238 | {
|
---|
| 239 | pixel OUT;
|
---|
| 240 |
|
---|
[2884] | 241 | float4 col = tex2Dlod(colors, float4(IN.texCoord.xy, 0, 0));
|
---|
[2880] | 242 | float4 ao = tex2D(ssaoTex, IN.texCoord.xy);
|
---|
| 243 |
|
---|
[2990] | 244 | OUT.illum_col = col * ao.x;
|
---|
| 245 | //OUT.illum_col = float4(ao.x,ao.x,ao.x, ao.w);
|
---|
[2975] | 246 | OUT.illum_col.w = col.w;
|
---|
[2880] | 247 |
|
---|
| 248 | return OUT;
|
---|
[2873] | 249 | } |
---|