就是normalize(eyedir+lightdir)求一个halfwaydir
eyedir=eyepos-fragpos lightdir=lightpos-fragpos fragpos=a_position*model
pow(max( dot(eyedir,halfwaydir),0) ,material.shininess)=spec
specular = light.specular * spec *vec3(texture(material.specular, v_texcoord));
然后就求出来高光了
VERT
#ifdef GL_ES
// Set default precision to medium
precision mediump int;
precision mediump float;
#endif
uniform mat4 mvp_matrix;
uniform mat4 model;
//uniform mat3 transpose_inverse_model;
attribute vec4 a_position;
attribute vec2 a_texcoord;
attribute vec3 a_normal;
varying vec2 v_texcoord;
varying vec3 fragPos;
varying vec3 normal;
//! [0]
void main()
{
// Calculate vertex position in screen space
gl_Position = mvp_matrix * a_position;
fragPos=vec3(model*a_position);
normal=mat3(transpose(inverse(model)))*a_normal;//model的逆矩阵的转置的左上角3x3矩阵
// // Pass texture coordinate to fragment shader
// Value will be automatically interpolated to fragments inside polygon faces
v_texcoord = a_texcoord;
}
//! [0]
FRAG
#ifdef GL_ES
// Set default precision to medium
precision mediump int;
precision mediump float;
#endif
struct Material
{
sampler2D diffuse;
sampler2D specular;
float shininess;
};
struct Light {
vec3 position;
vec3 ambient;
vec3 diffuse;
vec3 specular;
};
uniform Material material;
uniform Light light;
//uniform sampler2D texture;
uniform vec3 viewPos;
//uniform vec3 lightPos;
//uniform vec3 lightColor;
varying vec2 v_texcoord;
varying vec3 fragPos;
varying vec3 normal;
//! [0]
void main()
{
vec4 ans;
//float ambientStrength=0.1;
vec3 ambient = light.ambient *vec3(texture(material.diffuse, v_texcoord));//环境光
// diffuse
vec3 norm = normalize(normal);
vec3 lightDir = normalize(light.position - fragPos);
float diff = max(dot(norm, lightDir), 0.0);
vec3 diffuse = light.diffuse*diff * vec3(texture(material.diffuse, v_texcoord));//漫反射
// specular
vec3 viewDir = normalize(viewPos - fragPos);
vec3 halfwayDir=normalize(lightDir+viewDir);//blinn phong
//vec3 reflectDir = reflect(-lightDir, norm);//phong
float spec = pow(max(dot(viewDir, halfwayDir), 0.0), material.shininess);
vec3 specular = light.specular * spec *vec3(texture(material.specular, v_texcoord));
vec3 result = ambient + diffuse + specular;
//vec3 result = (ambient + diffuse)*texture(material.specular,v_texcoord).rgb;
//float
gl_FragColor = vec4(result,1.0);
}
//! [0]