对象/三角形的纹理是在片段着色器还是顶点着色器中进行映射的?
无论是在顶点着色器还是片段着色器中,如果你正在编写着色器,那么这是你必须自己编码的内容,对吧?没有着色器时,你只需分配纹理坐标,OpenGL会在你不知道的情况下进行映射,但使用着色器时,你必须自己完成此过程,对吧?
对象/三角形的纹理是在片段着色器还是顶点着色器中进行映射的?
无论是在顶点着色器还是片段着色器中,如果你正在编写着色器,那么这是你必须自己编码的内容,对吧?没有着色器时,你只需分配纹理坐标,OpenGL会在你不知道的情况下进行映射,但使用着色器时,你必须自己完成此过程,对吧?
varying vec3 vertex;
varying vec3 normal;
varying vec3 eye;
uniform sampler2D DiffuseMap;
void computeLight(in int i, inout vec4 ambient, inout vec4 diffuse, inout vec4 specular)
{
ambient += gl_LightSource[i].ambient * gl_FrontMaterial.ambient;
vec3 light;
if(gl_LightSource[i].position.w == 1.0)
light = gl_LightSource[i].position.xyz - vertex;
else
light = gl_LightSource[i].position.xyz;
vec3 lightDiri = normalize(light);
float NdotL = max(0.0, dot(normal, lightDiri));
if(NdotL > 0.0)
{
float att = 1.0;
// Calcule l'attinuation dans le cas d'une lumier pointctuelle
if(gl_LightSource[i].position.w == 1.0)
{
float distance = length(light);
att = 1.0 / (gl_LightSource[i].constantAttenuation
+ gl_LightSource[i].linearAttenuation
* distance
+ gl_LightSource[i].quadraticAttenuation
* distance
* distance);
}
float NdotHV = dot(normal, normalize(lightDiri + eye));
diffuse += gl_FrontMaterial.diffuse * gl_LightSource[i].diffuse * NdotL * att;
specular += gl_FrontMaterial.specular * gl_LightSource[i].specular * pow(NdotHV, gl_FrontMaterial.shininess) * NdotL * att;
}
}
void main()
{
vec4 ambient = vec4(0);
vec4 diffuse = vec4(0);
vec4 specular = vec4(0);
vec4 finalColor = vec4(0);
computeLight(0, ambient, diffuse, specular);
finalColor = ambient + diffuse * shadow;
finalColor *= gl_Color;
// *** This is what you asking for !
finalColor *= texture2D(DiffuseMap, gl_TexCoord[0].st);
finalColor += specular;
// Foged ?
float z = gl_FragCoord.z / gl_FragCoord.w;
float fogFactor = (gl_Fog.end - z) / (gl_Fog.end - gl_Fog.start);
fogFactor = clamp(fogFactor, 0.0, 1.0);
gl_FragColor = mix(gl_Fog.color, finalColor, fogFactor);
gl_FragColor *= finalColor.aaaa;
}
和顶点着色器相关
varying vec3 vertex;
varying vec3 normal;
varying vec3 eye;
void main()
{
vertex = vec3(gl_ModelViewMatrix * gl_Vertex);
normal = normalize(gl_NormalMatrix * gl_Normal);
eye = -normalize(vertex);
gl_FrontColor = gl_Color;
gl_TexCoord[0].xy = gl_MultiTexCoord0.xy;
gl_Position = ftransform();
gl_ClipVertex = gl_ModelViewMatrix*gl_Vertex;
}