Question

概述

我一直在研究一个OpenGL 3.3渲染引擎，好消息是，如果我硬编码对象的值，它们将完美渲染。坏消息是，当试图加载 .obj文件时，我遇到了严重的问题。

我使用GLFW，GLM和GLEW并不重要，它可能会有所帮助。

N.B。我的.obj加载程序基于找到的here。

问题

当我运行我的代码时，我得到错误：

Debug Assertion失败！
行：1201
表达式：矢量下标超出范围

我如何修复它？！

我已经调试了代码，我知道哪些行导致错误但是在进一步挖掘时我发现它试图索引下标'0'的向量，所以我试图将一些值初始化到容器但是错误仍然存在

代码

以下是所有代码，请向下滚动以查看其具体细节。

OBJLoader.cpp

bool OBJLoader::loadGLDataFromOBJ(){

    bool processed = false;
    while (true){

        char currentLine[128];
        int res = fscanf(file, "%s", currentLine);
        if (res == EOF){

            break;
        }

        if (strcmp(currentLine, "v") == 0){
            Vector3f vertex;
            fscanf(file, "%f %f %f\n", &vertex.x, &vertex.y, &vertex.z);
            raw_vPositions.push_back(vertex);
        }
        else if (strcmp(currentLine, "vt") == 0){
            Vector2f uv;
            fscanf(file, "%f %f\n", &uv.x, &uv.y);
            raw_vTextureCoords.push_back(uv);
        }
        else if (strcmp(currentLine, "vn") == 0){
            Vector3f normal;
            fscanf(file, "%f %f %f\n", &normal.x, &normal.y, &normal.z);
            raw_vNormals.push_back(normal);
        }
        else if (strcmp(currentLine, "f") == 0){
            unsigned int vertexData1[3], vertexData2[3], vertexData3[3];
            int matches = fscanf(file, "%d/%d/%d %d/%d/%d %d/%d/%d\n",
                &vertexData1[0], &vertexData1[0], &vertexData1[0],
                &vertexData2[1], &vertexData2[1], &vertexData2[1],
                &vertexData3[2], &vertexData3[2], &vertexData3[2]);
            if (matches != 9){
                printf("File can't be read by our simple parser : ( Try exporting with other options\n");
                return false;
            }

            if (!processed){
                gl_vTextureCoords.resize(raw_vPositions.size() * 2);
                gl_vNormals.resize(raw_vPositions.size() * 3);
                processed = true;
            }

            processVertex(vertexData1);
            processVertex(vertexData2);
            processVertex(vertexData3);
        }
    }

    gl_vPositions.resize(raw_vPositions.size() * 3);
    gl_vIndexBuffer.resize(indices.size());

    int vertexPointer = 0;
    for (int i = 0; i < raw_vPositions.size(); i++){
        gl_vPositions[vertexPointer++] = raw_vPositions[i].x;
        gl_vPositions[vertexPointer++] = raw_vPositions[i].y;
    }

    for (int j = 0; j < indices.size(); j++) gl_vIndexBuffer[j] = indices[j];

    return true;
}

void OBJLoader::processVertex(unsigned int vertexData[]){
    int currentVertexPointer = *(vertexData) - 1;
    indices.push_back(currentVertexPointer);

    Vector2f currentTexture = raw_vTextureCoords[*(vertexData+1) - 1];
    gl_vTextureCoords[currentVertexPointer * 2] = currentTexture.x;
    gl_vTextureCoords[currentVertexPointer * 2 + 1] = currentTexture.y;

    Vector3f currentNormal = raw_vNormals[*(vertexData + 2) - 1];
    gl_vNormals[currentVertexPointer * 3] = currentNormal.x;
    gl_vNormals[currentVertexPointer * 3 + 1] = currentNormal.y;
    gl_vNormals[currentVertexPointer * 3 + 2] = currentNormal.z;

}


bool OBJLoader::loadOBJFromFile(const char* filePath){
    file = fopen(filePath, "r");
    if (!file){
        printf("Impossible to open the file !\n");
        return false;
    }
    else{
        printf("File opened: %s", filePath);
    }
    return true;
}



std::vector<float> OBJLoader::getPositions(){
    return this->gl_vPositions;
}
std::vector<float> OBJLoader::getTextureCoords(){
    return this->gl_vTextureCoords;
}
std::vector<float> OBJLoader::getNormals(){
    return this->gl_vNormals;
}
std::vector<unsigned short> OBJLoader::getIndexData(){
    return this->gl_vIndexBuffer;
}

OBJLoader.h

#include "glm/glm.hpp"
#include <vector>

typedef glm::vec3 Vector3f;
typedef glm::vec2 Vector2f;

typedef std::vector<Vector3f> List_Vec3;
typedef std::vector<Vector2f> List_Vec2;
typedef std::vector<unsigned short> List_Int;

class OBJLoader{
private:
    //These will be populated and then outputted to the user.
    std::vector<unsigned short> gl_vIndexBuffer = std::vector<unsigned short>(10);
    std::vector<float> gl_vPositions = std::vector<float>(10);
    std::vector<float> gl_vTextureCoords = std::vector<float>(10);
    std::vector<float> gl_vNormals = std::vector<float>(10);

    //These come from the obj file.
    List_Int indices;
    List_Vec3 raw_vPositions;
    List_Vec2 raw_vTextureCoords;
    List_Vec3 raw_vNormals;

    FILE* file; //The file of the obj.

    //Private functions
    bool loadOBJFromFile(const char* filePath); //Populates the file.
    bool loadGLDataFromOBJ();

    void processVertex(unsigned int[]);

public:
    OBJLoader(){}; //The default constructor.

    bool loadGLDataFromFile(const char* filePath); //Returns true if data loaded.

    std::vector<float> getPositions();
    std::vector<float> getTextureCoords();
    std::vector<float> getNormals();
    std::vector<unsigned short> getIndexData();

};

详细

它的这个功能似乎让我感到悲伤：

void OBJLoader::processVertex(unsigned int vertexData[]){
    int currentVertexPointer = *(vertexData) - 1;
    indices.push_back(currentVertexPointer);

    Vector2f currentTexture = raw_vTextureCoords[*(vertexData+1) - 1];
    gl_vTextureCoords[currentVertexPointer * 2] = currentTexture.x;
    gl_vTextureCoords[currentVertexPointer * 2 + 1] = currentTexture.y;

    Vector3f currentNormal = raw_vNormals[*(vertexData + 2) - 1];
    gl_vNormals[currentVertexPointer * 3] = currentNormal.x;
    gl_vNormals[currentVertexPointer * 3 + 1] = currentNormal.y;
    gl_vNormals[currentVertexPointer * 3 + 2] = currentNormal.z;
}

更具体地说，这些行：

gl_vTextureCoords[currentVertexPointer * 2] = currentTexture.x;
gl_vTextureCoords[currentVertexPointer * 2 + 1] = currentTexture.y;

gl_vNormals[currentVertexPointer * 3] = currentNormal.x;
gl_vNormals[currentVertexPointer * 3 + 1] = currentNormal.y;
gl_vNormals[currentVertexPointer * 3 + 2] = currentNormal.z;

出于某种原因，如果我继续踩过while循环，它会在第一次迭代时中断，并且在检查下标的值时，它等于0，因此它调用类似于：

gl_vTextureCoords[0] = currentTexture.x;
gl_vTextureCoords[1] = currentTexture.y;

理论和实践都应该存在。在类i中定义了向量将使用10个空值进行初始化，并且在循环达到其'f'值时的运行中，无论如何它都会调整列表的大小，那么为什么零为如此硬数？

Answer 1

错误在这里

unsigned int vertexData1[3], vertexData2[3], vertexData3[3];
int matches = fscanf(file, "%d/%d/%d %d/%d/%d %d/%d/%d\n",
   &vertexData1[0], &vertexData1[0], &vertexData1[0],
   &vertexData2[1], &vertexData2[1], &vertexData2[1],
   &vertexData3[2], &vertexData3[2], &vertexData3[2]);

我很确定你的意思是：

unsigned int vertexData1[3], vertexData2[3], vertexData3[3];
int matches = fscanf(file, "%d/%d/%d %d/%d/%d %d/%d/%d\n",
   &vertexData1[0], &vertexData1[1], &vertexData1[2],
   &vertexData2[0], &vertexData2[1], &vertexData2[2],
   &vertexData3[0], &vertexData3[1], &vertexData3[2]);

或者也许：

unsigned int vertexData1[3], vertexData2[3], vertexData3[3];
int matches = fscanf(file, "%d/%d/%d %d/%d/%d %d/%d/%d\n",
   &vertexData1[0], &vertexData2[0], &vertexData3[0],
   &vertexData1[1], &vertexData2[1], &vertexData3[1],
   &vertexData1[2], &vertexData3[2], &vertexData3[2]);

这是一个很好的例子，说明为什么老式的“C”式编程是一种垂死的艺术 - 很容易犯下难以诊断后果的简单错误。

向量下标超出范围错误 - 如何修复此SPECIFIC错误？

概述

问题

代码

详细

1 个答案: