OpenGL 3.1 使用索引绘图渲染纹理时出现问题

我正在尝试使用 glDrawElements 绘制从 assimp 加载的模型，几何图形显示良好，但纹理没有显示在模型上，我只是得到了我加载的模型的黑色版本。

荷载模型函数

ModelInfo LoadModel(const std::string& modelPath){
printf( "Loading model: %sn", modelPath.c_str());
//verify that file exists first
std::ifstream fin(modelPath.c_str());
if(!fin.fail()){
    fin.close();
}else{
    throw std::runtime_error("could not open file" + modelPath);
}
Assimp::Importer importer;
const aiScene* scene = importer.ReadFile( modelPath,
        aiProcessPreset_TargetRealtime_Fast |
        //aiProcess_CalcTangentSpace      |
        aiProcess_Triangulate           |
        aiProcess_GenSmoothNormals      |
        aiProcess_FlipUVs
    //aiProcess_JoinIdenticalVertices |
    //aiProcess_SortByPType);
);
if(!scene){
    throw std::runtime_error(importer.GetErrorString());
}
printf("imported %sn",modelPath.c_str());
fflush(stdout);
std::vector<unsigned int> indices;
std::vector<float> vertices;
std::vector<float> uvs;
std::vector<float> normals;
aiMesh* mesh = scene->mMeshes[0];
int numOfFaces = mesh->mNumFaces;
int numOfIndices = numOfFaces * 3;
indices.resize(numOfIndices);
for (unsigned int i =0; i < mesh->mNumFaces; ++i){
    const aiFace &face = mesh->mFaces[i];
    assert(face.mNumIndices == 3);
    indices[i * 3 + 0] = face.mIndices[0];
    indices[i * 3 + 1] = face.mIndices[1];
    indices[i * 3 + 2] = face.mIndices[2];
}
int numOfVertices = mesh->mNumVertices;
vertices.resize(numOfVertices * 3);
normals.resize(numOfVertices * 3);
uvs.resize(numOfVertices * 2);
for( unsigned int i = 0; i < mesh->mNumVertices; ++i){
    if(mesh->HasPositions()){
        vertices[i * 3 + 0] = mesh->mVertices[i].x;
        vertices[i * 3 + 1] = mesh->mVertices[i].y;
        vertices[i * 3 + 2] = mesh->mVertices[i].z;
        //printf("[ %f, %f, %f]n",vertices[i*3+0],vertices[i*3+1],vertices[i*3+2]);
    }

    if( mesh->HasNormals()){
        normals[i * 3 + 0] = mesh->mNormals[i].x;
        normals[i * 3 + 1] = mesh->mNormals[i].x;
        normals[i * 3 + 2] = mesh->mNormals[i].x;
    }
    if(mesh->HasTextureCoords(0)){
        uvs[i * 2 + 0] = mesh->mTextureCoords[0][i].x;
        uvs[i * 2 + 1] = mesh->mTextureCoords[0][i].y;
        printf("[ %f, %f]n",uvs[i*2+0],uvs[i*2+1]);
    }
}
//create voa
GLuint vao;
glGenVertexArrays(1, &vao);
glBindVertexArray(vao);
//create element buffer
GLuint elementBuffer;
glGenBuffers(1, &elementBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, elementBuffer);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, indices.size() * sizeof(unsigned int), &indices[0], GL_STATIC_DRAW);
//create vertex buffer
GLuint vertexBuffer;
glGenBuffers(1, &vertexBuffer);
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(aiVector3D), &vertices[0], GL_STATIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
printf("vertices.size is %lun", vertices.size());
printf("uvs.size is %lun", uvs.size());
GLuint uvBuffer;
glGenBuffers(1, &uvBuffer);
glBindBuffer(GL_ARRAY_BUFFER, uvBuffer);
glBufferData(GL_ARRAY_BUFFER, uvs.size() * sizeof(aiVector2D), &uvs[0], GL_STATIC_DRAW);
glEnableVertexAttribArray(1);
glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 2*sizeof(float), (void*)0);
GLuint normalBuffer;
glGenBuffers(1, &normalBuffer);
glBindBuffer(GL_ARRAY_BUFFER, normalBuffer);
glBufferData(GL_ARRAY_BUFFER, normals.size() * sizeof(aiVector3D), &normals[0], GL_STATIC_DRAW);
glEnableVertexAttribArray(2);
glVertexAttribPointer(2, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
ModelInfo retval;
retval.vao    = vao;
retval.index  = elementBuffer;
retval.vertex = vertexBuffer;
retval.uv     = uvBuffer;
retval.normal = normalBuffer;
retval.count  = numOfIndices;
return retval;

}

加载模型的简短概述，使用 assimp 加载模型，然后将来自 assimp 场景中第一个网格的数据加载到向量中，然后为几何体、纹理坐标、法线和索引创建 vao、vbos。然后将数据从矢量加载到缓冲区中，并设置顶点属性。加载完所有内容后，将创建一个包含多个 GLuint 的结构来返回数据。

渲染模型功能

void render_model(ModelInfo info){
cleanup();
//set program
glUseProgram(modelprogram);
//set uniforms
glm::mat4 view = camera.matrix();
glUniformMatrix4fv(modelcamera, 1, GL_FALSE, &view[0][0]);
glm::mat4 model = glm::mat4();
model = glm::rotate(model, degree, glm::vec3(0,1,1));
glUniformMatrix4fv(modelmodel, 1, GL_FALSE, &model[0][0]);
glBindVertexArray(info.vao);
glBindTexture(GL_TEXTURE_2D, texture);
glUniform1i(modeltext, texture);
glDrawElements(GL_TRIANGLES, info.count, GL_UNSIGNED_INT, (void*)0);
}

渲染模型的简要概述。设置着色器程序以处理模型的渲染，获取相机的矩阵，将其传递给着色器，为模型生成矩阵，使其旋转，将其传递给着色器。绑定要渲染的模型的 vao。绑定以前加载的文本，该文本也用于程序中显示没有问题的其他几何体，将其传递给着色器。全部设置好，从当前 vao 索引缓冲区中的第一个位置开始调用 glDrawElements。绘制完成后，进行清理以取消绑定任何缓冲区和数组

我为此使用的着色器是非常基本的顶点着色器

#version 140
uniform mat4 camera;
uniform mat4 model;
in vec3 position;
in vec2 uv;
out vec2 fragUV;
void main(){
    //pass variables on to fragment shader
    fragUV   = uv;
    //vertex to draw
    gl_Position = camera * model * vec4(position,1);
}

片段着色器 #version 140

uniform sampler2D modeltext;
in vec2 fragUV;
out vec4 finalColor;
void main(){
    finalColor = texture(modeltext, fragUV);
}

所有制服都正确加载了一个功能，该功能可以验证某些东西是否实际加载，纹理被使用并在程序中的其他位置工作。模型具有纹理坐标。几何体正在加载和渲染没有问题