OpenGL - VAO,VBO,IBO,glDrawElements不显示

Question

我无法将我的关卡数据显示在屏幕上.我正在使用我的着色器正确渲染立方体而不是水平.

这是我的VBO,VAO和IBO的设置:

void ZoneMesh::buildData()
{
    // Create the VBO for this mesh
    glGenBuffers(1, &vbo);
    glBindBuffer(GL_ARRAY_BUFFER, vbo);
    glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);

    // Create the IBO
    glGenBuffers(1, &ibo);
    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ibo);
    glBufferData(GL_ELEMENT_ARRAY_BUFFER, numPoly * 3 * sizeof(short), indices, GL_STATIC_DRAW);

    // Create the VAO
    glGenVertexArraysAPPLE(1, &vao);
    glBindVertexArrayAPPLE(vao);

    // Bind the VBO to the buffer and set up the attributes
    glBindBuffer(GL_ARRAY_BUFFER, vbo);
    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), BUFFER_OFFSET(0));
    glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), BUFFER_OFFSET(sizeof(float)*3));
    glVertexAttribPointer(2, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), BUFFER_OFFSET(sizeof(float)*5));

    //Bind the IBO to the VAO
    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ibo);
}

这是我的顶点结构:

struct Vertex
{
    float x;
    float y;
    float z;
    float u;
    float v;
    float normX;
    float normY;
    float normZ;
};

以下是ZoneMesh类中的相关数据项:

Vertex* vertices;
short* indices;

GLuint vbo;
GLuint vao;
GLuint ibo;

顶点着色器:

#version 120

attribute vec3 position;

uniform mat4 camera;

void main()
{
    gl_Position = camera * vec4(position, 1.0f);
}

片段着色器:

#version 120

void main(void)
{
    gl_FragColor = vec4(0.0, 0.6, 0.7, 1.0);
}

渲染:

    shader.Use();

    // Testing - render the first 50 meshes
    for(int i = 0; i < 50; i++)
    {

        glUniformMatrix4fv(shader("camera"), 1, GL_FALSE, glm::value_ptr(MVPMatrix));

        glEnableVertexAttribArray(shader["position"]);
        glBindVertexArrayAPPLE(zone.getVAO(i));
        glDrawElements(GL_TRIANGLES, 500, GL_UNSIGNED_SHORT, NULL);

    }

    shader.UnUse();

渲染/着色器使用不是问题.MVPMatrix是正确的.我在它上方正确渲染了一个立方体.该区域不会渲染.

Answer 1

GL_LINE不是glDrawElements您想要的有效原语GL_LINES。

在您的代码中使用glGetError()来查找此类问题！