Files
Nuake/Editor/resources/Shaders/ssao.shader
2023-03-13 22:18:00 -04:00

139 lines
3.4 KiB
GLSL

#shader vertex
#version 460 core
layout(location = 0) in vec3 VertexPosition;
layout(location = 1) in vec2 UVPosition;
out flat vec2 UV;
out mat4 v_InvView;
out mat4 v_InvProjection;
out mat4 v_View;
uniform mat4 u_View;
uniform mat4 u_Projection;
void main()
{
v_View = u_View;
v_InvView = inverse(u_View);
v_InvProjection = inverse(u_Projection);
UV = UVPosition;
gl_Position = vec4(VertexPosition, 1.0f);
}
#shader fragment
#version 460 core
uniform sampler2D u_Depth;
uniform sampler2D u_Normal;
uniform sampler2D u_Noise;
uniform int u_KernelSize = 64;
uniform vec3 u_Samples[64];
uniform mat4 u_Projection;
uniform vec2 u_NoiseScale;
uniform float u_Radius = 0.5f;
uniform float u_Bias = 0.025f;
uniform float u_Falloff = 0.0022;
uniform float u_Area = 0.0075;
uniform float u_Strength = 2.0f;
in vec2 UV;
in mat4 v_View;
in mat4 v_InvView;
in mat4 v_InvProjection;
out vec4 FragColor;
vec3 WorldPosFromDepth(float depth)
{
float z = depth * 2.0 - 1.0;
vec4 clipSpacePosition = vec4(UV * 2.0 - 1.0, z, 1.0);
vec4 viewSpacePosition = v_InvProjection * clipSpacePosition;
// Perspective division
viewSpacePosition /= viewSpacePosition.w;
vec4 worldSpacePosition = v_InvView * viewSpacePosition;
return worldSpacePosition.xyz;
}
vec3 ViewPosFromDepth(float depth)
{
float z = depth * 2.0 - 1.0;
vec4 clipSpacePosition = vec4(UV * 2.0 - 1.0, z, 1.0);
vec4 viewSpacePosition = v_InvProjection * clipSpacePosition;
viewSpacePosition.xyz /= viewSpacePosition.w;
return viewSpacePosition.xyz;
}
vec3 normal_from_depth(float depth, vec2 texcoords) {
const vec2 offset1 = vec2(0.0,0.0002);
const vec2 offset2 = vec2(0.0002,0.0);
float depth1 = texture(u_Depth, UV + offset1).r;
float depth2 = texture(u_Depth, UV + offset2).r;
vec3 p1 = vec3(offset1, depth1 - depth);
vec3 p2 = vec3(offset2, depth2 - depth);
vec3 normal = cross(p1, p2);
normal.z = -normal.z;
return normalize(normal);
}
void main()
{
float depth = texture(u_Depth, UV).r ;
vec3 fragPos = ViewPosFromDepth(depth);
if(depth > 0.9999999f)
{
FragColor = vec4(0, 0, 0, 0);
return;
}
vec3 goodNormal = normal_from_depth(depth, UV);
vec3 normal = texture(u_Normal, UV).rgb * 2.0 - 1.0;
vec4 normalT = v_View * vec4(normal, 1.0);
normalT *= -1.0f;
normal = normalT.xyz;
normal = normalize(normal);
normal = goodNormal;
normal = normalT.xyz;
vec3 randomVec = texture(u_Noise, UV * u_NoiseScale).xyz;
float radius_depth = u_Radius/depth;
float occlusion = 0.0;
vec3 position = vec3(UV, depth);
int skipped = 0;
for(int i=0; i < 64; i++)
{
vec3 ray = radius_depth * reflect(u_Samples[i], randomVec);
/*
if(dot(normal, normalize(ray)) < u_Falloff)
{
skipped++;
continue;
}*/
vec3 hemi_ray = position + sign(dot(ray, normal)) * ray;
float occ_depth = texture(u_Depth, hemi_ray.xy).r;
float difference = depth - occ_depth + u_Bias;
float rangeCheck = smoothstep(0.0, 1.0, u_Radius * 10.0 / abs(depth - occ_depth));
//float rangeCheck = abs(depth - occ_depth) < u_Radius ? 1.0 : 0.0;
occlusion += ( occ_depth <= hemi_ray.z - u_Bias ? 1.0 : 0.0) * rangeCheck;
}
float ao = 1.0 - u_Strength * occlusion * (1.0 / (64 ));
FragColor = vec4(ao, ao, ao , 1.0);
}