glDrawElements GL_OUT_OF_MEMORY

Question

我试图启动下一个代码，但它在glDrawElements行(GL_TRIANGLES，6，GL_UNSIGNED_INT，nullptr((Application.cpp(上出现代码1285错误。

如果我用glDrawArrays(GL_TRIANGLES，0，3(替换前一行代码，它会绘制一个三角形，所以着色器、顶点缓冲区和顶点数组绑定都可以正常工作。问题应该在IndexBuffer中，但我找不到。

渲染器.h

#pragma once
#include <GL/glew.h>
#define ASSERT(x) if (!(x)) __debugbreak();
#define GLCall(x) GLClearError();
x;
ASSERT(GLLogCall(#x, __FILE__, __LINE__))
void GLClearError();
bool GLLogCall(const char* function, const char* file, int line);

Renderer.cpp

#include "Renderer.h"
#include <iostream>
void GLClearError()
{
while (glGetError() != GL_NO_ERROR);
}
bool GLLogCall(const char* function, const char* file, int line)
{
while (GLenum error = glGetError())
{
std::cout << "[OpenGL Error] (" << error << "): " << function <<
" " << file << ": " << line << std::endl;
return false;
}
return true;
}

VertexBuffer.h

#pragma once
class VertexBuffer
{
private:
unsigned int m_RendererID;
public:
VertexBuffer(const void* data, unsigned int size);
~VertexBuffer();
void Bind() const;
void Unbind() const;

};

VertexBuffer.cpp

#include "VertexBuffer.h"
#include "Renderer.h"

VertexBuffer::VertexBuffer(const void* data, unsigned int size)

{
GLCall(glGenBuffers(1, &m_RendererID));
GLCall(glBindBuffer(GL_ARRAY_BUFFER, m_RendererID));
GLCall(glBufferData(GL_ARRAY_BUFFER, size, data, GL_STATIC_DRAW));
}
VertexBuffer::~VertexBuffer()
{
GLCall(glDeleteBuffers(1, &m_RendererID));
}
void VertexBuffer::Bind() const
{
GLCall(glBindBuffer(GL_ARRAY_BUFFER, m_RendererID));
}
void VertexBuffer::Unbind() const
{
GLCall(glBindBuffer(GL_ARRAY_BUFFER, 0));
}

IndexBuffer.h

#pragma once
class IndexBuffer
{
private:
unsigned int m_RendererID;
unsigned int m_Count;
public:
IndexBuffer(const unsigned int* data, unsigned int count);
~IndexBuffer();
void Bind() const;
void Unbind() const;
inline unsigned int GetCount() const { return m_Count; }
};

IndexBuffer.cpp

#include "IndexBuffer.h"
#include "Renderer.h"
IndexBuffer::IndexBuffer(const unsigned int* data, unsigned int count)
: m_Count(count)
{
ASSERT(sizeof(unsigned int) == sizeof(GLuint));
GLCall(glGenBuffers(1, &m_RendererID));
GLCall(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_RendererID));
GLCall(GL_ELEMENT_ARRAY_BUFFER, count * sizeof(unsigned int), data, GL_STATIC_DRAW);
}
IndexBuffer::~IndexBuffer()
{
GLCall(glDeleteBuffers(1, &m_RendererID));
}
void IndexBuffer::Bind() const
{
GLCall(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_RendererID));
}
void IndexBuffer::Unbind() const
{
GLCall(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0));
}

Application.cpp

#pragma once
#include <GL/glew.h>
#include <GLFW/glfw3.h>

#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
#include "Renderer.h"
#include "VertexBuffer.h"
#include "IndexBuffer.h"

struct ShaderProgramSource
{
std::string VertexSource;
std::string FragmentSource;
};
static ShaderProgramSource ParseShader(const std::string& filepath)
{
std::fstream stream(filepath);
enum class ShaderType
{
NONE = -1, VERTEX = 0, FRAGMENT = 1
};
std::string line;
std::stringstream ss[2];
ShaderType type = ShaderType::NONE;
while (getline(stream, line))
{
if (line.find("#shader") != std::string::npos) 
{
if (line.find("vertex") != std::string::npos)
{
type = ShaderType::VERTEX;
}
else if (line.find("fragment") != std::string::npos)
{
type = ShaderType::FRAGMENT;
}
}
else 
{
ss[(int)type] << line << 'n';
}
}
return { ss[0].str(), ss[1].str() };
}
static unsigned int CompileShader(unsigned int type, const std::string& source)
{
GLCall(unsigned int id = glCreateShader(type));
const char* src = source.c_str();
GLCall(glShaderSource(id, 1, &src, nullptr));
GLCall(glCompileShader(id));
int result;
GLCall(glGetShaderiv(id, GL_COMPILE_STATUS, &result));
if (result == GL_FALSE) 
{
int length;
GLCall(glGetShaderiv(id, GL_INFO_LOG_LENGTH, &length));
char* message = (char*)alloca(length * sizeof(char));
GLCall(glGetShaderInfoLog(id, length, &length, message));
std::cout << "Failed to compile " << (type == GL_VERTEX_SHADER ? "vertex" : "fragment") << " shader!" << std::endl;
std::cout << message << std::endl;

GLCall(glDeleteShader(id));
return 0;
}
return id;
}
static unsigned int CreateProgram(const std::string& vertexShader, const std::string& fragmentShader)
{
GLCall(unsigned int program = glCreateProgram());
unsigned int vs = CompileShader(GL_VERTEX_SHADER, vertexShader);
unsigned int fs = CompileShader(GL_FRAGMENT_SHADER, fragmentShader);
GLCall(glAttachShader(program, vs));
GLCall(glAttachShader(program, fs));
GLCall(glLinkProgram(program));
GLCall(glValidateProgram(program));
GLCall(glDeleteShader(vs));
GLCall(glDeleteShader(fs));
return program;
}

int main()
{
GLFWwindow* window;
if (!glfwInit())
{
return -1;
}
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
window = glfwCreateWindow(640, 400, "Hello world", NULL, NULL);
if (!window)
{
glfwTerminate();
return -1;
}

glfwMakeContextCurrent(window);
glfwSwapInterval(1);
if (glewInit() != GLEW_OK)
{
std::cout << "Error while GLEW init!" << std::endl;
}
std::cout << glGetString(GL_VERSION) << std::endl;
{
float positions[] = {
-0.5f, -0.5f,  // 0
0.5f, -0.5f,  // 1
0.5f,  0.5f,  // 2
-0.5f,  0.5f  // 3
};
unsigned int indices[] = {
0, 1, 2,
2, 3, 0
};
unsigned int vao;
GLCall(glGenVertexArrays(1, &vao));
GLCall(glBindVertexArray(vao));
VertexBuffer vb(positions, 4 * 2 * sizeof(float));
GLCall(glEnableVertexAttribArray(0));
GLCall(glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, sizeof(float) * 2, 0));
IndexBuffer ib(indices, 6);
ShaderProgramSource source = ParseShader("res/shaders/Basic.shader");
unsigned int program = CreateProgram(source.VertexSource, source.FragmentSource);
GLCall(glUseProgram(program));
GLCall(int location = glGetUniformLocation(program, "u_Color"));
ASSERT(location != -1);
GLCall(glUniform4f(location, 0.8f, 0.3f, 0.8f, 1.0f));
GLCall(glBindVertexArray(0));
GLCall(glUseProgram(0));
vb.Unbind();
ib.Unbind();
float r = 0;
float increment = 0.05f;
while (!glfwWindowShouldClose(window))
{
GLCall(glClear(GL_COLOR_BUFFER_BIT));
glClearColor(1, 0, 0, 1);
GLCall(glUseProgram(program));
GLCall(glUniform4f(location, r, 0.3f, 0.8f, 1.0f));
GLCall(glBindVertexArray(vao));
ib.Bind();

//  glDrawArrays(GL_TRIANGLES, 0, 3);
GLCall(glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, nullptr));
if (r > 1.0f)
{
increment = -0.05f;
}
else if (r < 0.0f)
{
increment = 0.05f;
}
r += increment;

glfwSwapBuffers(window);

glfwPollEvents();
}
GLCall(glDeleteProgram(program));
}
glfwTerminate();

return 0;
}

基本着色器

#shader vertex
#version 330 core
layout(location = 0) in vec4 position;
void main()
{
gl_Position = position;
}
#shader fragment
#version 330 core
layout(location = 0) out vec4 color;
uniform vec4 u_Color;
void main()
{
color = u_Color;
}

Answer 1

这看起来不对。缺少glBufferData？

GLCall(GL_ELEMENT_ARRAY_BUFFER, count * sizeof(unsigned int), data, GL_STATIC_DRAW);