game-engine/resources/shaders/light_shader.glsl

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4.1 KiB
GLSL

#version 330 core
out vec4 FragColor;
in vec3 Normal;
in vec2 TexCoords;
in vec3 FragPos;
struct DirLight {
vec3 direction;
vec3 color;
vec3 ambient;
vec3 diffuse;
vec3 specular;
};
struct PointLight {
vec3 position;
vec3 ambient;
vec3 diffuse;
vec3 specular;
vec3 color;
float constant;
float linear;
float quadratic;
};
struct SpotLight {
vec3 position;
vec3 direction;
vec3 ambient;
vec3 diffuse;
vec3 specular;
vec3 color;
float constant;
float linear;
float quadratic;
float cutOff;
float outerCutOff;
};
uniform sampler2D texture_diffuse1;
uniform vec3 viewPos;
uniform DirLight dirLight;
#define NR_POINT_LIGHTS 16
uniform PointLight pointLights[NR_POINT_LIGHTS];
uniform int pointLightCount;
uniform SpotLight spotLight;
vec3 CalcDirLight(DirLight light, vec3 normal, vec3 viewDir)
{
// ambient
float ambientStrength = 0.1;
vec3 ambient = ambientStrength * light.color;
// diffuse
vec3 norm = normalize(Normal);
vec3 lightDir = normalize(-light.direction);
float diff = max(dot(norm, lightDir), 0.0);
vec3 diffuse = diff * light.color;
// specular
float specularStrength = 0.5;
vec3 reflectDir = reflect(-lightDir, norm);
float spec = pow(max(dot(viewDir, reflectDir), 0.0), 32);
vec3 specular = specularStrength * spec * light.color;
return (ambient + diffuse + specular);
}
vec3 CalcPointLight(PointLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
{
float distance = length(light.position - FragPos);
float attenuation = 1.0 / (light.constant + light.linear * distance + light.quadratic * (distance * distance));
// ambient// ambient
float ambientStrength = 0.1;
vec3 ambient = ambientStrength * light.color;
// diffuse
vec3 norm = normalize(Normal);
vec3 lightDir = normalize(light.position - FragPos);
float diff = max(dot(norm, lightDir), 0.0);
vec3 diffuse = diff * light.color;
// specular
float specularStrength = 0.5;
vec3 reflectDir = reflect(-lightDir, norm);
float spec = pow(max(dot(viewDir, reflectDir), 0.0), 32);
vec3 specular = specularStrength * spec * light.color;
ambient *= attenuation;
diffuse *= attenuation;
specular *= attenuation;
return (ambient + diffuse + specular);
}
vec3 CalcSpotLight(SpotLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
{
// Calculate the direction of the light
vec3 lightDir = normalize(light.position - FragPos);
// Calculate the angle between the light direction and the spotlight direction
float theta = dot(lightDir, normalize(-light.direction));
float epsilon = light.cutOff - light.outerCutOff;
float intensity = clamp((theta - light.outerCutOff) / epsilon, 0.0, 1.0);
float distance = length(light.position - FragPos);
float attenuation = 1.0 / (light.constant + light.linear * distance + light.quadratic * (distance * distance));
// ambient
float ambientStrength = 0.1;
vec3 ambient = ambientStrength * light.color;
// diffuse
vec3 norm = normalize(Normal);
float diff = max(dot(norm, lightDir), 0.0);
vec3 diffuse = diff * light.color;
// specular
float specularStrength = 0.5;
vec3 reflectDir = reflect(-lightDir, norm);
float spec = pow(max(dot(viewDir, reflectDir), 0.0), 32);
vec3 specular = specularStrength * spec * light.color;
// Apply attenuation and intensity
ambient *= attenuation;
diffuse *= attenuation * intensity;
specular *= attenuation * intensity;
return (ambient + diffuse + specular);
}
void main()
{
// properties
vec3 norm = normalize(Normal);
vec3 viewDir = normalize(viewPos - FragPos);
// phase 1: Directional lighting
vec3 result = CalcDirLight(dirLight, norm, viewDir);
// phase 2: Point lights
for(int i = 0; i < pointLightCount; i++)
result += CalcPointLight(pointLights[i], norm, FragPos, viewDir);
// phase 3: Spot light
result += CalcSpotLight(spotLight, norm, FragPos, viewDir);
FragColor = texture(texture_diffuse1, TexCoords) * vec4(result, 1.0);
}