Space-Project/shaders/shader_parallax.frag
2021-02-25 20:52:49 +01:00

107 lines
3.3 KiB
GLSL

#version 430 core
layout (location = 0) out vec4 FragColor;
layout (location = 1) out vec4 BrightColor;
struct PointLight {
vec3 position;
vec3 color;
float intensity;
};
#define MAX_POINT_LIGHTS 16
uniform vec3 cameraPos;
uniform sampler2D diffuseTexture;
uniform sampler2D normalTexture;
uniform sampler2D depthTexture;
uniform PointLight pointLights[MAX_POINT_LIGHTS];
uniform int LightsCount;
in vec3 fragPos;
in vec2 vTexCoord;
in vec3 LightPosTS[MAX_POINT_LIGHTS];
in vec3 CameraPosTS;
in vec3 FragPosTS;
vec2 ParallaxMapping(vec2 texCoords, vec3 viewDir)
{
// number of depth layers
const float minLayers = 8;
const float maxLayers = 32;
float numLayers = mix(maxLayers, minLayers, abs(dot(vec3(0.0, 0.0, 1.0), viewDir)));
// calculate the size of each layer
float layerDepth = 1.0 / numLayers;
// depth of current layer
float currentLayerDepth = 0.0;
// the amount to shift the texture coordinates per layer (from vector P)
vec2 P = viewDir.xy / viewDir.z * 0.001;
vec2 deltaTexCoords = P / numLayers;
// get initial values
vec2 currentTexCoords = texCoords;
float currentdepthTextureValue = texture(depthTexture, currentTexCoords).r;
while(currentLayerDepth < currentdepthTextureValue)
{
// shift texture coordinates along direction of P
currentTexCoords -= deltaTexCoords;
// get depthTexture value at current texture coordinates
currentdepthTextureValue = texture(depthTexture, currentTexCoords).r;
// get depth of next layer
currentLayerDepth += layerDepth;
}
// get texture coordinates before collision (reverse operations)
vec2 prevTexCoords = currentTexCoords + deltaTexCoords;
// get depth after and before collision for linear interpolation
float afterDepth = currentdepthTextureValue - currentLayerDepth;
float beforeDepth = texture(depthTexture, prevTexCoords).r - currentLayerDepth + layerDepth;
// interpolation of texture coordinates
float weight = afterDepth / (afterDepth - beforeDepth);
vec2 finalTexCoords = prevTexCoords * weight + currentTexCoords * (1.0 - weight);
return finalTexCoords;
}
void main()
{
vec3 fragColor = vec3(0,0,0);
vec3 V = normalize(CameraPosTS-FragPosTS);
vec2 texCoords = ParallaxMapping(vTexCoord, V);
if(texCoords.x > 1.0 || texCoords.y > 1.0 || texCoords.x < 0.0 || texCoords.y < 0.0)
discard;
vec3 texture = texture2D(diffuseTexture, texCoords).rgb;
//vec3 texture = vec3(textureColor.x, textureColor.y, textureColor.z);
vec3 ambient = vec3(0.1, 0.1, 0.1) * texture;
vec3 normal = texture2D(normalTexture, texCoords).rgb;
normal = normalize(normal * 2.0 - 1.0);
for(int i = 0; i < LightsCount; i++)
{
vec3 lightDir = normalize(LightPosTS[i] - FragPosTS);
vec3 R = reflect(-lightDir,normal);
float dist = distance(fragPos, pointLights[i].position);
float distance = (1/dist) * (1/dist);
float spec = pow(max(0,dot(R,V)),2);
float diff = max(0,dot(normal,lightDir));
vec3 diffuse = pointLights[i].color * diff * distance * pointLights[i].intensity;
vec3 specular = spec * pointLights[i].color * (pointLights[i].intensity/dist);
fragColor += texture*(diffuse+specular);
}
BrightColor = vec4(0.0, 0.0, 0.0, 1.0);
FragColor = vec4(fragColor+ambient,1.0);
}