Question

我试图用this tutorial学习OpenGL我尝试在OS X Mavericks中进行编码，但结果只是一个黑色的窗口。我相信应该有一个白色的三角形，但不知道我错过了什么。

这是代码

glut_utils.h

#include <GLUT/glut.h>
#include <OpenGL/gl.h>

void init();
void display();
void reshape (int w, int h);
void keyboard(uchar key, int x, int y);

glut_utils.cpp

#include <string>
#include <vector>

#include "glut_utils.h"

GLuint CreateShader(GLenum eShaderType, const std::string &strShaderFile)
{
    GLuint shader = glCreateShader(eShaderType);
    const char *strFileData = strShaderFile.c_str();
    glShaderSource(shader, 1, &strFileData, NULL);

    glCompileShader(shader);

    GLint status;
    glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
    if (status == GL_FALSE)
    {
        GLint infoLogLength;
        glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &infoLogLength);

        GLchar *strInfoLog = new GLchar[infoLogLength + 1];
        glGetShaderInfoLog(shader, infoLogLength, NULL, strInfoLog);

        const char *strShaderType = NULL;
        switch(eShaderType)
        {
            case GL_VERTEX_SHADER: strShaderType = "vertex"; break;
            case GL_GEOMETRY_SHADER_EXT: strShaderType = "geometry"; break;
            case GL_FRAGMENT_SHADER: strShaderType = "fragment"; break;
        }

        fprintf(stderr, "Compile failure in %s shader:\n%s\n", strShaderType, strInfoLog);
        delete[] strInfoLog;
    }

    return shader;
}

GLuint CreateProgram(const std::vector<GLuint> &shaderList)
{
    GLuint program = glCreateProgram();

    for(size_t iLoop = 0; iLoop < shaderList.size(); iLoop++)
        glAttachShader(program, shaderList[iLoop]);

    glLinkProgram(program);

    GLint status;
    glGetProgramiv (program, GL_LINK_STATUS, &status);
    if (status == GL_FALSE)
    {
        GLint infoLogLength;
        glGetProgramiv(program, GL_INFO_LOG_LENGTH, &infoLogLength);

        GLchar *strInfoLog = new GLchar[infoLogLength + 1];
        glGetProgramInfoLog(program, infoLogLength, NULL, strInfoLog);
        fprintf(stderr, "Linker failure: %s\n", strInfoLog);
        delete[] strInfoLog;
    }

    for(size_t iLoop = 0; iLoop < shaderList.size(); iLoop++)
        glDetachShader(program, shaderList[iLoop]);

    return program;
}

GLuint theProgram;

const std::string strVertexShader(
    "#version 330\n"
    "layout(location = 0) in vec4 position;\n"
    "void main()\n"
    "{\n"
    "   gl_Position = position;\n"
    "}\n"
);

const std::string strFragmentShader(
    "#version 330\n"
    "out vec4 outputColor;\n"
    "void main()\n"
    "{\n"
    "   outputColor = vec4(1.0f, 1.0f, 1.0f, 1.0f);\n"
    "}\n"
);

void InitializeProgram()
{
    std::vector<GLuint> shaderList;

    shaderList.push_back(CreateShader(GL_VERTEX_SHADER, strVertexShader));
    shaderList.push_back(CreateShader(GL_FRAGMENT_SHADER, strFragmentShader));

    theProgram = CreateProgram(shaderList);

    std::for_each(shaderList.begin(), shaderList.end(), glDeleteShader);
}

const float vertexPositions[] = {
    0.75f, 0.75f, 0.0f, 1.0f,
    0.75f, -0.75f, 0.0f, 1.0f,
    -0.75f, -0.75f, 0.0f, 1.0f,
};

GLuint positionBufferObject;
GLuint vao;

void InitializeVertexBuffer()
{
    glGenBuffers(1, &positionBufferObject);

    glBindBuffer(GL_ARRAY_BUFFER, positionBufferObject);
    glBufferData(GL_ARRAY_BUFFER, sizeof(vertexPositions), vertexPositions, GL_STATIC_DRAW);
    glBindBuffer(GL_ARRAY_BUFFER, 0);
}

//Called after the window and OpenGL are initialized. Called exactly once, before the main loop.
void init()
{
    InitializeProgram();
    InitializeVertexBuffer();

    glGenVertexArraysAPPLE(1, &vao);
    glBindVertexArrayAPPLE(vao);
}

void display()
{
    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
    glClear(GL_COLOR_BUFFER_BIT);

    glUseProgram(theProgram);

    glBindBuffer(GL_ARRAY_BUFFER, positionBufferObject);
    glEnableVertexAttribArray(0);
    glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, 0, 0);

    glDrawArrays(GL_TRIANGLES, 0, 3);

    glDisableVertexAttribArray(0);
    glUseProgram(0);

    glutSwapBuffers();
}

void reshape (int w, int h)
{
    glViewport(0, 0, (GLsizei) w, (GLsizei) h);
    glLoadIdentity();
}

void keyboard(unsigned char key, int x, int y)
{
    switch (key)
    {
        case 27:
            exit(EXIT_SUCCESS);
            return;
    }

}

Tut01.cpp

#include "common.h"
#include "glut_utils.h"

int main(int argc, char **argv)
{
    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_3_2_CORE_PROFILE | GLUT_DOUBLE | GLUT_ALPHA | GLUT_DEPTH | GLUT_STENCIL);

    glutInitWindowSize(500, 500);
    glutInitWindowPosition(0, 0);
    glutCreateWindow("Hello Triangle");

    init();

    glutDisplayFunc(display);
    glutIdleFunc(display);
    glutReshapeFunc(reshape);
    glutKeyboardFunc(keyboard);

    glutMainLoop();

    return 0;
}

Answer 1

首先尝试包含核心配置文件标头：

#include <OpenGL/gl3.h>
#include <GLUT/glut.h>

从APPLE和glGenVertexArraysAPPLE移除glBindVertexArrayAPPLE后缀 - 无论如何都不应使用gl3.h标题定义它们。

OpenGL不渲染os x mavericks

1 个答案: