311 lines
8.5 KiB
GLSL
311 lines
8.5 KiB
GLSL
#version 430
|
|
#extension GL_NV_uniform_buffer_std430_layout : enable
|
|
|
|
uniform mat4 P;
|
|
uniform mat4 V;
|
|
uniform mat4 M;
|
|
uniform vec3 cam_pos;
|
|
uniform int window_width;
|
|
uniform int window_height;
|
|
|
|
uniform vec3 la;
|
|
uniform vec3 ld;
|
|
uniform vec3 ls;
|
|
uniform vec3 ka;
|
|
uniform vec3 kd;
|
|
uniform vec3 ks;
|
|
|
|
uniform float smoothing;
|
|
uniform vec3 sphere_center;
|
|
|
|
const uint P_SPHERE = 0x00;
|
|
const uint P_TORUS = 0x01;
|
|
const uint P_CONE = 0x02;
|
|
const uint P_CUBE = 0x03;
|
|
|
|
struct GLSLPrimitive
|
|
{
|
|
vec4 position;
|
|
vec4 diffuse_color;
|
|
vec4 specular_color;
|
|
vec4 ambient_color;
|
|
|
|
uint specular_exponent;
|
|
|
|
uint type;
|
|
|
|
float radius;
|
|
float height;
|
|
float inner_radius;
|
|
float outer_radius;
|
|
float size;
|
|
uint dummy;
|
|
};
|
|
|
|
layout(std430, binding = 0) buffer PrimitiveBuffer
|
|
{
|
|
GLSLPrimitive primitives[];
|
|
};
|
|
|
|
out vec4 FragColor;
|
|
|
|
struct NormalEstimationData
|
|
{
|
|
vec3 normal;
|
|
float minDistance;
|
|
float secondMinDistance;
|
|
float smoothMinDistance;
|
|
GLSLPrimitive closestPrimitive;
|
|
GLSLPrimitive secondClosestPrimitive;
|
|
};
|
|
|
|
|
|
|
|
float sphereSDF(vec3 p, vec3 center, float r)
|
|
{
|
|
return length(p - center) - r;
|
|
}
|
|
|
|
float torusSDF(vec3 p, vec3 center, float R, float r)
|
|
{
|
|
vec2 q = vec2(length(p.xz - center.xz) - R, p.y - center.y);
|
|
return length(q) - r;
|
|
}
|
|
|
|
float coneSDF(vec3 p, vec3 center, float h, float r)
|
|
{
|
|
vec2 d = abs(vec2(length(p.xz), p.y)) - vec2(r, h);
|
|
return length(d) < 0.0 ? max(d.x, -d.y) : length(max(d, vec2(0)));
|
|
}
|
|
|
|
float cubeSDF(vec3 p, vec3 c, float s)
|
|
{
|
|
float x = max(p.x - c.x - (s / 2.0), c.x - p.x - (s / 2.0));
|
|
float y = max(p.y - c.y - (s / 2.0),c.y - p.y - (s / 2.0));
|
|
float z = max(p.z - c.z - (s / 2.0),c.z - p.z - (s / 2.0));
|
|
|
|
float d = x;
|
|
d = max(d, y);
|
|
d = max(d, z);
|
|
|
|
return d;
|
|
}
|
|
|
|
float sdf(vec3 pos, GLSLPrimitive prim)
|
|
{
|
|
float d;
|
|
switch (prim.type)
|
|
{
|
|
case P_SPHERE:
|
|
{
|
|
d = sphereSDF(pos, prim.position.xyz, prim.radius);
|
|
break;
|
|
}
|
|
case P_TORUS:
|
|
{
|
|
d = torusSDF(pos, prim.position.xyz, prim.outer_radius, prim.inner_radius);
|
|
break;
|
|
}
|
|
case P_CONE:
|
|
{
|
|
d = coneSDF(pos, prim.position.xyz, prim.height, prim.radius);
|
|
break;
|
|
}
|
|
case P_CUBE:
|
|
{
|
|
d = cubeSDF(pos, prim.position.xyz, prim.size);
|
|
break;
|
|
}
|
|
default:
|
|
{
|
|
d = 0.0;
|
|
break;
|
|
}
|
|
}
|
|
return d;
|
|
}
|
|
|
|
float smoothMinSDF(float d1, float d2, float k)
|
|
{
|
|
if (k == 0.0) k = 0.000001;
|
|
float h = max(k - abs(d1 - d2), 0) / k;
|
|
return min(d1, d2) - h * h * h * k * 1.0 / 6.0;
|
|
}
|
|
|
|
float smoothMaxSDF(float d1, float d2, float k)
|
|
{
|
|
if (k == 0.0) k = 0.000001;
|
|
float h = min(k - abs(d1 - d2), 0) / k;
|
|
return min(d1, d2) - h * h * h * k * 1.0 / 6.0;
|
|
}
|
|
|
|
void estimateSmoothNormals(vec3 p, float smoothness, float epsilon, inout vec3 normals, inout vec4 color)
|
|
{
|
|
float d = sdf(p, primitives[0]);
|
|
float nx = sdf(vec3(p.x + epsilon, p.y, p.z), primitives[0]);
|
|
float ny = sdf(vec3(p.x, p.y + epsilon, p.z), primitives[0]);
|
|
float nz = sdf(vec3(p.x, p.y, p.z + epsilon), primitives[0]);
|
|
|
|
float blendFactor = clamp(0.5 + 0.5 * (sdf(p, primitives[0]) - sdf(p, primitives[1])) / smoothness, 0.0, 1.0);
|
|
vec4 blendedColor = mix(primitives[0].diffuse_color, primitives[1].diffuse_color, blendFactor);
|
|
|
|
blendFactor = clamp(0.5 + 0.5 * (sdf(p, primitives[1]) - sdf(p, primitives[2])) / smoothness, 0.0, 1.0);
|
|
vec4 blendedColor1 = mix(primitives[1].diffuse_color, primitives[2].diffuse_color, blendFactor);
|
|
|
|
blendFactor = clamp(0.5 + 0.5 * (sdf(p, primitives[2]) - sdf(p, primitives[0])) / smoothness, 0.0, 1.0);
|
|
vec4 blendedColor2 = mix(primitives[2].diffuse_color, primitives[0].diffuse_color, blendFactor);
|
|
|
|
vec4 blendedColor3 = mix(blendedColor, blendedColor1, blendFactor);
|
|
vec4 blendedColor4 = mix(blendedColor3, blendedColor2, blendFactor);
|
|
|
|
|
|
for (int i = 1; i < primitives.length(); i++)
|
|
{
|
|
d = smoothMinSDF(d, sdf(p, primitives[i]), smoothness);
|
|
nx = smoothMinSDF(nx, sdf(vec3(p.x + epsilon, p.y, p.z), primitives[i]), smoothness);
|
|
ny = smoothMinSDF(ny, sdf(vec3(p.x, p.y + epsilon, p.z), primitives[i]), smoothness);
|
|
nz = smoothMinSDF(nz, sdf(vec3(p.x, p.y, p.z + epsilon), primitives[i]), smoothness);
|
|
|
|
/*blendFactor = clamp(0.5 + 0.5 * (sdf(p, primitives[i-1]) - sdf(p, primitives[i])) / smoothness, 0.0, 1.0);
|
|
blendedColor = mix(primitives[i-1].diffuse_color, primitives[i].diffuse_color, blendFactor);*/
|
|
}
|
|
nx -= d;
|
|
ny -= d;
|
|
nz -= d;
|
|
|
|
normals = normalize(vec3(nx, ny, nz));
|
|
//color = blendedColor4;
|
|
}
|
|
|
|
vec3 estimateNormals(vec3 p, GLSLPrimitive prim, float epsilon)
|
|
{
|
|
float x = sdf(vec3(p.x + epsilon, p.y, p.z), prim) - sdf(vec3(p.x - epsilon, p.y, p.z), prim);
|
|
float y = sdf(vec3(p.x, p.y + epsilon, p.z), prim) - sdf(vec3(p.x, p.y - epsilon, p.z), prim);
|
|
float z = sdf(vec3(p.x, p.y, p.z + epsilon), prim) - sdf(vec3(p.x, p.y, p.z - epsilon), prim);
|
|
return normalize(vec3(x, y, z));
|
|
}
|
|
|
|
//vec3 estimateNormalsMax(vec3 p, float smoothness) {
|
|
// float epsilon = 0.001;
|
|
// float d = max(torusSDF(p, torus.center, torus.R, torus.r), sphereSDF(p, sphere.center, sphere.r));
|
|
// float nx = max(torusSDF(vec3(p.x + epsilon, p.y, p.z), torus.center, torus.R, torus.r), sphereSDF(vec3(p.x + epsilon, p.y, p.z), sphere.center, sphere.r)) - d;
|
|
// float ny = max(torusSDF(vec3(p.x, p.y + epsilon, p.z), torus.center, torus.R, torus.r), sphereSDF(vec3(p.x, p.y + epsilon, p.z), sphere.center, sphere.r)) - d;
|
|
// float nz = max(torusSDF(vec3(p.x, p.y, p.z + epsilon), torus.center, torus.R, torus.r), sphereSDF(vec3(p.x, p.y, p.z + epsilon), sphere.center, sphere.r)) - d;
|
|
// return normalize(vec3(nx, ny, nz));
|
|
//}
|
|
|
|
vec4 blendColors(vec4 color1, vec4 color2, float blendFactor)
|
|
{
|
|
return mix(color1, color2, blendFactor);
|
|
}
|
|
|
|
float weightFunction(float distance, float k, float epsilon) {
|
|
//// Ensure 'k' is positive to avoid division by zero.
|
|
//k = max(k, 0.0001);
|
|
//// Sigmoid-like smooth transition function.
|
|
//return (k*k*k)/distance;
|
|
|
|
if (k <= 0.0) {
|
|
// When k is zero, return 1 if the distance is zero (object is closest), else return 0.
|
|
return distance <= 0.001 ? 1.0 : 0.0;
|
|
}
|
|
else {
|
|
// As k increases, the transition becomes smoother.
|
|
return (k * k * k) / distance;
|
|
}
|
|
}
|
|
|
|
void main(void)
|
|
{
|
|
vec3 normals;
|
|
vec3 color = la;
|
|
vec4 ray_pos = vec4(cam_pos, 1.0);
|
|
float ray_dist = 0.0;
|
|
float max_dist = 100.0;
|
|
float epsilon = 0.0001;
|
|
int steps = 0;
|
|
int max_steps = 1000;
|
|
vec3 light_pos = vec3(0.0, 1.0, 0.0);
|
|
int spec_exponent = 40;
|
|
float k = smoothing;
|
|
|
|
vec2 ndc_pos = 2.0 * vec2(gl_FragCoord.x / window_width, gl_FragCoord.y / window_height) - 1.0;
|
|
vec4 cam_dir = inverse(P) * vec4(ndc_pos, 1.0, 1.0);
|
|
cam_dir /= cam_dir.w;
|
|
cam_dir = vec4(cam_dir.xyz, 0.0);
|
|
|
|
vec4 ray_dir = normalize(inverse(V) * cam_dir);
|
|
|
|
vec4 accumulatedColor = vec4(0.0);
|
|
float totalWeight = 0.0;
|
|
|
|
int closestIndex = -1;
|
|
int secClosestIndex = -1;
|
|
|
|
while (ray_dist < max_dist && steps < max_steps)
|
|
{
|
|
steps++;
|
|
float minDist = 999999.0;
|
|
|
|
for (int i = 0; i < primitives.length(); i++)
|
|
{
|
|
float dist = sdf(ray_pos.xyz, primitives[i]);
|
|
float weight = weightFunction(dist, smoothing, epsilon);
|
|
if (dist < sdf(ray_pos.xyz, primitives[closestIndex]))
|
|
{
|
|
secClosestIndex = closestIndex;
|
|
closestIndex = i;
|
|
}
|
|
/*else if (dist < sdf(ray_pos.xyz, primitives[secClosestIndex]))
|
|
{
|
|
secClosestIndex = i;
|
|
}*/
|
|
minDist = smoothMinSDF(minDist, dist, k);
|
|
|
|
accumulatedColor += primitives[i].diffuse_color * weight;
|
|
totalWeight += weight;
|
|
}
|
|
|
|
|
|
|
|
if (minDist <= epsilon)
|
|
{
|
|
if (totalWeight > 0.0) {
|
|
accumulatedColor /= totalWeight;
|
|
}
|
|
|
|
vec4 ambient_color, diffuse_color;
|
|
|
|
float blendFactor = clamp(0.5 + 0.5 * (sdf(ray_pos.xyz, primitives[closestIndex]) - sdf(ray_pos.xyz, primitives[secClosestIndex])) / k, 0.0, 1.0);
|
|
vec4 blendedColor = mix(primitives[closestIndex].diffuse_color, primitives[secClosestIndex].diffuse_color, blendFactor);
|
|
|
|
ambient_color = primitives[closestIndex].ambient_color;
|
|
diffuse_color = vec4(accumulatedColor.rgb, 1.0);
|
|
|
|
vec4 ambient = vec4(la, 1.0) * ambient_color;
|
|
|
|
//normals = estimateNormals(ray_pos.xyz, primitives[closestIndex], epsilon);
|
|
estimateSmoothNormals(ray_pos.xyz, k, epsilon, normals, diffuse_color);
|
|
|
|
vec3 nw = normalize(normals);
|
|
vec3 lw = normalize(light_pos - ray_pos.xyz);
|
|
float dist = length(vec4(ray_pos.xyz - light_pos, 1.0));
|
|
vec4 diffuse = max(dot(nw, lw), 0) * diffuse_color * vec4(ld, 1.0);
|
|
|
|
float spec;
|
|
vec3 vw = normalize(cam_pos - ray_pos.xyz);
|
|
|
|
vec3 halfwayDir = normalize(lw + vw);
|
|
spec = pow(max(dot(halfwayDir, nw), 0), spec_exponent);
|
|
|
|
vec4 specular = spec * vec4(primitives[closestIndex].specular_color.rgb * ls, 1.0);
|
|
|
|
color = (ambient + (1.0 / (dist * dist) * (diffuse + specular))).xyz;
|
|
break;
|
|
}
|
|
ray_pos += ray_dir * minDist;
|
|
ray_dist += minDist;
|
|
}
|
|
|
|
FragColor = vec4(color, 1.0);
|
|
} |