问OpenGL中光谱照明的故障

EN

#version 330

layout (location = 0) in vec3 Position;
layout (location = 1) in vec3 Normal;

out vec4 Colour0;

// Transforms
uniform mat4 gModelToWorldTransform;
uniform mat4 gWorldToViewToProjectionTransform;

// Ambient light parameters
uniform vec3 gAmbientLightIntensity;

// Directional light parameters
uniform vec3 gDirectionalLightIntensity;
uniform vec3 gDirectionalLightDirection;

// Material constants
uniform float gKa;
uniform float gKd;
uniform float gKs;
uniform float gKsStrength;

                                                                   
void main()
{  
    // Transform the vertex from local space to homogeneous clip space 
    vec4 vertexPositionInModelSpace = vec4(Position, 1);
    vec4 vertexInWorldSpace = gModelToWorldTransform * vertexPositionInModelSpace;
    vec4 vertexInHomogeneousClipSpace = gWorldToViewToProjectionTransform * vertexInWorldSpace;
    gl_Position = vertexInHomogeneousClipSpace;

    // Calculate the directional light intensity at the vertex
    // Find the normal in world space and normalise it
    vec3 normalInWorldSpace = (gModelToWorldTransform * vec4(Normal, 0.0)).xyz;
    normalInWorldSpace = normalize(normalInWorldSpace);

    // Calculate the ambient light intensity at the vertex
    // Ia = Ka * ambientLightIntensity
    vec4 ambientLightIntensity = gKa * vec4(gAmbientLightIntensity, 1.0);

    // Setup the light direction and normalise it
    vec3 lightDirection = normalize(-gDirectionalLightDirection);
    
    //lightDirection = normalize(gDirectionalLightDirection);
    // Id = kd * lightItensity * N.L
    // Calculate N.L
    float diffuseFactor = dot(normalInWorldSpace, lightDirection);
    diffuseFactor = clamp(diffuseFactor, 0.0, 1.0);

    // N.L * light source colour * intensity
    vec4 diffuseLightIntensity = gKd * vec4(gDirectionalLightIntensity, 1.0f) * diffuseFactor;

    vec3 lightReflect = normalize(reflect(gDirectionalLightDirection, Normal));

    //Calculate the specular light intensity at the vertex
    float specularFactor = dot(normalInWorldSpace, lightReflect);
    specularFactor = pow(specularFactor, gKsStrength);
    vec4 specularLightIntensity = gKs * vec4(gDirectionalLightIntensity, 1.0f) * specularFactor;
   
    // Final vertex colour is the product of the vertex colour
    // and the total light intensity at the vertex 

    vec4 colour = vec4(0.0, 1.0, 0.0, 1.0);
    Colour0 = colour * (ambientLightIntensity + diffuseLightIntensity + specularLightIntensity);
}

// Lighting uniforms location

GLuint gAmbientLightIntensityLoc;
GLuint gDirectionalLightIntensityLoc;
GLuint gDirectionalLightDirectionLoc;
GLuint gSpecularLightIntensityLoc;

// Materials uniform location
GLuint gKaLoc;
GLuint gKdLoc;
GLuint gKsLoc;
GLuint gKsStrengthLoc;

// Set the material properties
glUniform1f(gKaLoc, 0.2f); 
glUniform1f(gKdLoc, 0.9f);
glUniform1f(gKsLoc, 0.5f);
glUniform1f(gKsStrengthLoc, 0.5f);

static void initLights()
{
    // Setup the ambient light
    vec3 ambientLightIntensity = vec3(0.2f, 0.2f, 0.2f);
    glUniform3fv(gAmbientLightIntensityLoc, 1, &ambientLightIntensity[0]);
    
    // Setup the direactional light
    vec3 directionalLightDirection = vec3(0.0f, 0.0f, -1.0f);
    normalize(directionalLightDirection);
    glUniform3fv(gDirectionalLightDirectionLoc, 1, &directionalLightDirection[0]);

    vec3 directionalLightIntensity = vec3(0.8f, 0.8f, 0.8f);
    glUniform3fv(gDirectionalLightIntensityLoc, 1, &directionalLightIntensity[0]);

    //Setup the specular Light
    vec3 specularLightIntensity = vec3(0.5f, 0.5f, 0.5f);
    glUniform3fv(gSpecularLightIntensityLoc, 1, &specularLightIntensity[0]);
}

gKsStrengthLoc = glGetUniformLocation(shaderProgram, "gKsStrength");
    //assert(gDirectionalLightDirectionLoc != 0xFFFFFFFF);