如何用颜色绘制gluQuadric

Question

struct quadricObj {
GLUquadricObj* obj;
GLenum drawmode{ GLU_FILL };
GLdouble radius{1.0};
GLint slices{20};
GLint stacks{20};
glm::vec3 col{ 1.0,0.0,0.0 };
std::vector<glm::mat4> M;
glm::mat4 world_M() {
glm::mat4 WM(1.0f);
std::for_each(this->M.begin(), this->M.end(), [&WM](glm::mat4& m) { WM *= m; });
//M0*M1*M2 TRS
return WM;
}
GLvoid draw() {
gluQuadricDrawStyle(this->obj, this->drawmode);
glUniformMatrix4fv(worldLoc, 1, GL_FALSE, glm::value_ptr(this->world_M()));
glColor4f(this->col.r, this->col.g, this->col.b, 1.0f); // doesn't work.
gluSphere(this->obj, this->radius, this->slices, this->stacks);
}
};

这是我的结构，用于使用quadratObj。我认为glColor4f必须工作，但不行。二次曲面保持黑色。如何在GL中为二次曲面着色？

#version 330
in vec3 v_normal;
in vec2 v_texCoord;
in vec3 v_color;
in vec3 fragPos;
out vec4 gl_FragColor;
uniform vec3 lightColor;
uniform vec3 lightPos;
uniform vec3 viewPos;
uniform float ambientLight;
uniform int shine;
void main(void)
{   
vec3 ambient = clamp(ambientLight*lightColor,0.0,1.0);
vec3 normalVector = normalize(v_normal);
vec3 lightDir = normalize(lightPos-fragPos);
float diffuseLight = max(dot(normalVector,lightDir),0.0); 
vec3 diffuse = clamp(diffuseLight * lightColor,0.0,1.0);
vec3 viewDir = normalize(viewPos-fragPos);
vec3 reflectDir = reflect(-lightDir,normalVector);
float specularLight = max(dot(viewDir,reflectDir),0.0);
specularLight = pow(specularLight,shine);
vec3 specular = clamp(specularLight*lightColor,0.0,1.0);
vec3 result = (ambient+diffuse)*v_color+specular*(0.8,0.8,0.8);
gl_FragColor = vec4(result,1.0);
}

我编辑我的片段着色器包含phong模型。这也可以与gluSphere一起使用吗？还是不？我也在使用顶点着色器。其具有inpos、col、nor、tex。以及CCD_ 4。

Answer 1

gluSphere不能与用户定义的顶点着色器输入变量(属性(一起使用。仅限于GLSL 1.20顶点着色器和"顶点着色器内置属性"。可以将GLSL 1.20顶点着色器与片段着色器相结合。

合适的顶点着色器可以如下所示：

#version 120
varying vec3 v_normal;
varying vec2 v_texCoord;
varying vec3 v_color;
varying vec3 fragPos;
uniform mat4 worldMatrix; // the matrix with the location worldLoc
void main()
{
v_color     = gl_Color.rgb;
v_texCoord  = gl_MultiTexCoord0.st;
v_normal    = mat3(worldMatrix) * gl_Normal;
fragPos     = (worldMatrix * gl_Vertex).xyz;
gl_Position = gl_ProjectionMatrix * worldMatrix * gl_Vertex;
}