OpenGL漫射光

Question

实施漫射光时遇到了一些问题 正确的结果可能看起来像左边的图片diffuse light picture
右侧结果不正确。
问题如下 1.开始时没有灯光效果。我必须在一定程度上旋转物体，才会出现灯光效果 物体中混有一些三角形。 （我已经检查了我的阅读文件（.obj＆amp; .mtl）部分。这是正确的。）

我只打开漫射光。但照明效果似乎是环境光 我的光源位置是（0,0,5），眼睛位置是（0,0,0）;

我的顶点着色器

attribute vec4 vertexPosition;
attribute vec3 vertexNormal_objectSpace;

varying vec4 vv4color;

uniform mat4 mvp; //model, viewing, projection transformation matrix
uniform mat4 NormalMatrix;

struct LightSourceParameters 
{
    vec4 ambient;
    vec4 diffuse;
    vec4 specular;
    vec4 position;
    vec4 halfVector;
    vec3 spotDirection;
    float spotExponent;
    float spotCutoff; // (range: [0.0,90.0], 180.0)
    float spotCosCutoff; // (range: [1.0,0.0],-1.0)
    float constantAttenuation;
    float linearAttenuation;
    float quadraticAttenuation;
};

struct MaterialParameters 
{
    vec4 ambient;
    vec4 diffuse;
    vec4 specular;
    float shininess;
};

uniform MaterialParameters Material;
uniform LightSourceParameters LightSource[3]; //because I have to implement three light sources(directional, point, specular light)  

void main() 
{
    vec3 normal, TransformedNormal, lightDirection;
    vec4 ambient, diffuse;                                      
    float NdotL;

    ambient = LightSource[0].ambient * Material.ambient;            
    TransformedNormal = vec3(vec4(vertexNormal_objectSpace, 0.0) * NormalMatrix);
    normal = normalize(TransformedNormal);                  
    lightDirection = normalize(vec3(LightSource[0].position));
    NdotL = max(dot(normal, lightDirection), 0.0);              
    diffuse = LightSource[0].diffuse * Material.diffuse * NdotL;    

    vv4color = ambient + diffuse; //vv4color pass to fragment shader
    gl_Position = mvp * vertexPosition;
}  

我的显示功能

void onDisplay(void)
{
    Matrix4 MVP, modelView, NormalMatrix;
    int i=0;

    // clear canvas
    glClearColor(0.5f, 0.0f, 0.0f, 1.0f);   
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glEnableVertexAttribArray(iLocPosition);
    glEnableVertexAttribArray(iLocNormal);

    geo_rotate = geo_rotate_x * geo_rotate_y * geo_rotate_z;
    Geo = geo_rotate * geo_scale * geo_trans;

    modelView = View * Geo; 
    modelView = modelView.transpose();  //row-major -> column-major 
    modelView = modelView.invert();     //normal transformation(transpose after inverse)
    NormalMatrix = modelView.transpose();

    MVP = Proj * View * Geo * Norm;
    MVP = MVP.transpose();  

    glUniformMatrix3fv(iLocEyePosition, 1, GL_FALSE, &eye[0]);  
    glUniformMatrix4fv(iLocNormalMatrix, 1, GL_FALSE, &NormalMatrix[0]);    //bind uniform matrix to shader
    glUniformMatrix4fv(iLocMVP, 1, GL_FALSE, &MVP[0]);

    group = OBJ->groups;
    for(i=0; i<OBJ->numgroups-1; i++)
    {
        //pass model material value to the shader
        glUniform4fv(iLocMAmbient, 1, material[i].ambient);
        glUniform4fv(iLocMDiffuse, 1, material[i].diffuse);
        glUniform4fv(iLocMSpecular, 1, material[i].specular);   
        glUniform1f(iLocMShininess, material[i].shininess);

        glVertexAttribPointer(iLocPosition, 3, GL_FLOAT, GL_FALSE, 0, V[i]);    //bind array pointers to shader
        glVertexAttribPointer(iLocNormal, 3, GL_FLOAT, GL_FALSE, 0, N[i]);
        glDrawArrays(GL_TRIANGLES, 0, group->numtriangles*3);                   //draw the array we just bound

        group = group->next;
    }
    glutSwapBuffers();
}

谢谢大家。