这是我的着色器程序：
#version 330 core
// Input vertex data, different for all executions of this shader.
layout(location = 0) in vec3 vertexPosition_modelspace;
layout(location = 1) in vec3 vertexNormal_modelspace;
// Values that stay constant for the whole mesh.
uniform mat4 MVP;
uniform mat4 V;
uniform mat4 M;
uniform mat3 blNormalMatrix;
uniform vec3 lightPos;
out vec4 forFragColor;
const vec3 diffuseColor = vec3(0.55, 0.09, 0.09);
void main(){
// Output position of the vertex, in clip space : MVP * position
gl_Position = MVP * vec4(vertexPosition_modelspace,1);
vec3 MaterialAmbientColor = vec3(0.1,0.1,0.1) * diffuseColor;
// all following gemetric computations are performed in the
// camera coordinate system (aka eye coordinates)
vec3 vertexNormal_cameraspace = (V*M*vec4(vertexNormal_modelspace,0)).xyz;
vec4 vertexPosition_cameraspace4 = V*M* vec4(vertexPosition_modelspace,1);
vec3 vertexPosition_cameraspace = vec3(vertexPosition_cameraspace4).xyz;
vec3 lightDir = normalize(lightPos - vertexPosition_cameraspace);
float lambertian = clamp(dot(lightDir,vertexNormal_cameraspace), 0.0,1.0);
forFragColor = vec4(lambertian*diffuseColor , 1.0);
}
我的问题是这个“工作”在旧的opengl配置文件中，甚至没有版本号，我认为它是在Opengl 2.1左右，关键的变化是我原来有正常= gl_normalMatrix * gl_normal和事情很有效。
然而，这是基于我的教授的代码，我已经更新到3.3+核心配置文件，在修改了已弃用的功能后，我现在还剩下这个：
https://drive.google.com/file/d/0B6oLZ_d7S-U7cVpkUXpVXzdaZEk/edit?usp=sharing是指向我的计划行为视频的链接。
光源应该是（0,0,3）左右的点光源，不应该移动;但是它没有遵循特别合乎逻辑的行为模式，我无法理解它。
我尝试传递模型矩阵的逆转置并将它们用作替换normalMatrix，但它破坏了我的法线。所以我不知道。
这是我的常规矩阵：
glm::mat3 MyNormalMatrix = glm::mat3(glm::transpose(glm::inverse(ModelMatrix)));
编辑：这是我的显示代码：
glClearColor(0.0f, 0.0f, 0.4f, 0.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glEnable(GL_DEPTH_TEST);
// Use our shader
glUseProgram(programID);
// Get our transformations iff we move the camera around.
glm::mat4 MyModelMatrix = ModelMatrix * thisTran * ThisRot;
MVP = ProjectionMatrix * ViewMatrix * MyModelMatrix;
glm::mat4 ModelView = ViewMatrix * MyModelMatrix;
glm::mat3 MyNormalMatrix = glm::mat3(glm::transpose(glm::inverse(ModelView)));
glm::vec3 newLightPos = lightPos;
// Send our transformation to the currently bound shader,
// in the "MVP" uniform
glUniformMatrix4fv(MatrixID, 1, GL_FALSE, &MVP[0][0]);
glUniformMatrix4fv(ModelMatrixID, 1, GL_FALSE, &MyModelMatrix[0][0]);
glUniformMatrix4fv(ViewMatrixID, 1, GL_FALSE, &ViewMatrix[0][0]);
glUniformMatrix4fv(BlNormalMatrix,1,GL_FALSE, &MyNormalMatrix[0][0]);
glUniformMatrix4fv(BlRotations, 1, GL_FALSE, &ThisRot[0][0]);
glUniform3f(BlCamera, cameraLoc.x, cameraLoc.y, cameraLoc.z);
glUniform3f(lPosition, newLightPos.x,newLightPos.y,newLightPos.z);
// VBO buffer: vertices
// 1rst attribute buffer : vertices
glEnableVertexAttribArray(0);
glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
glVertexAttribPointer(
0, // attribute
3, // size
GL_FLOAT, // type
GL_FALSE, // normalized?
0, // stride
(void*)0 // array buffer offset
);
// 2rd attribute buffer : normals
glEnableVertexAttribArray(1);
glBindBuffer(GL_ARRAY_BUFFER, normalbuffer);
glVertexAttribPointer(
1, // attribute
3, // size
GL_FLOAT, // type
GL_FALSE, // normalized?
0, // stride
(void*)0 // array buffer offset
);
// draw object using opengl 3.3 shit
glDrawArrays(GL_TRIANGLES, 0, vertices.size() );
答案 0 :(得分：0)
这个问题最终成了我教授提供的模型装载机的一个问题，它与现代的opengl不相容，只会“大部分”工作，因为它显然缺少左/右法线或者它们具有无效值。解决了使用Assimp的实现。
与assimp链接的代码是这样的：
void blInitResWAssimp() {
cout << "blInitResWAssimp" << endl;
blCreateModelViewProjectionMatrix();
//loads object
bool res = loadAssImp("Resources/RCSS-subdiv.obj", indices, indexed_vertices, indexed_uvs, indexed_normals);
//bool res = loadAssImp("Resources/cheb.obj", indices, indexed_vertices, indexed_uvs, indexed_normals);
glGenVertexArrays(1, &VertexArrayID);
glBindVertexArray(VertexArrayID);
// Load it into a VBO
glGenBuffers(1, &vertexbuffer);
glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
glBufferData(GL_ARRAY_BUFFER, indexed_vertices.size() * sizeof(glm::vec3), &indexed_vertices[0], GL_STATIC_DRAW);
// Normal buffer
glGenBuffers(1, &normalbuffer);
glBindBuffer(GL_ARRAY_BUFFER, normalbuffer);
glBufferData(GL_ARRAY_BUFFER, indexed_normals.size() * sizeof(glm::vec3), &indexed_normals[0], GL_STATIC_DRAW);
// Generate a buffer for the indices as well
glGenBuffers(1, &elementbuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, elementbuffer);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, indices.size() * sizeof(unsigned short), &indices[0], GL_STATIC_DRAW);
//ModelMatrix = ModelMatrix * glm::translate(glm::mat4(1.0f), glm::vec3(-0.5, -0.5, 0));
}
Assimp stuff
bool loadAssImp(
const char * path,
std::vector<unsigned short> & indices,
std::vector<glm::vec3> & vertices,
std::vector<glm::vec2> & uvs,
std::vector<glm::vec3> & normals
){
Assimp::Importer importer;
const aiScene* scene = importer.ReadFile(path, 0/*aiProcess_JoinIdenticalVertices | aiProcess_SortByPType*/);
if (!scene) {
fprintf(stderr, importer.GetErrorString());
getchar();
return false;
}
const aiMesh* mesh = scene->mMeshes[0]; // In this simple example code we always use the 1rst mesh (in OBJ files there is often only one anyway)
const aiMaterial* material = scene->mMaterials[0];
// Fill vertices positions
vertices.reserve(mesh->mNumVertices);
for (unsigned int i = 0; i<mesh->mNumVertices; i++){
aiVector3D pos = mesh->mVertices[i];
vertices.push_back(glm::vec3(pos.x, pos.y, pos.z));
}
// Fill vertices texture coordinates
/*
uvs.reserve(mesh->mNumVertices);
for (unsigned int i = 0; i<mesh->mNumVertices; i++){
aiVector3D UVW = mesh->mTextureCoords[0][i]; // Assume only 1 set of UV coords; AssImp supports 8 UV sets.
uvs.push_back(glm::vec2(UVW.x, UVW.y));
}*/
// Fill vertices normals
normals.reserve(mesh->mNumVertices);
for (unsigned int i = 0; i<mesh->mNumVertices; i++){
aiVector3D n = mesh->mNormals[i];
//aiVector3D n = mesh->mVertices[i];
normals.push_back(glm::vec3(n.x, n.y, n.z));
}
// Fill face ind5ices
indices.reserve(3 * mesh->mNumFaces);
for (unsigned int i = 0; i<mesh->mNumFaces; i++){
// Assume the model has only triangles.
indices.push_back(mesh->mFaces[i].mIndices[0]);
indices.push_back(mesh->mFaces[i].mIndices[1]);
indices.push_back(mesh->mFaces[i].mIndices[2]);
}
// The "scene" pointer will be deleted automatically by "importer"
}