使用 EBO 时 OpenGL 崩溃

Question

所以，这个有点特别，因为我不知道错误实际上来自哪里。我有一个 PyOpenGL 脚本，它应该使用 VBO、VAO 和 EBO 绘制带纹理的矩形。当我尝试运行终端中的程序时（我在 Ubuntu 16.04），它会创建一个空的、透明的 window，暂停一会儿，然后关闭 window 并在终端中发送一条 'Aborted' 消息。没有别的。

所以我想这可能是我这边的一个错误，所以这里有一些代码：

import math
import ctypes
import numpy as np
import glfw
from packages import shaderUtils
from PIL import Image
from OpenGL.GL import *

vert_shader_file = 'somename.vs'
frag_shader_file = 'somename.fs'

def main():

    glfw.init()
    glfw.window_hint(glfw.CONTEXT_VERSION_MAJOR, 4)
    glfw.window_hint(glfw.CONTEXT_VERSION_MINOR, 5)
    glfw.window_hint(glfw.OPENGL_PROFILE, glfw.OPENGL_CORE_PROFILE)

    window = glfw.create_window(800, 600, "helo wold", None, None)

    glfw.make_context_current(window)

    #----------TEXTURE STUFF-----------#

    texture = glGenTextures(1)
    glBindTexture(GL_TEXTURE_2D, texture)

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_MIRRORED_REPEAT)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_MIRRORED_REPEAT)

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR)

    textureFile = Image.open('container.jpg')
    textureWidth, textureHeight, textureData = textureFile.size[0], textureFile.size[1], np.array(list(textureFile.getdata()), np.int8) 

    if textureData.any():
        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, textureWidth, textureHeight, 0, GL_RGB, GL_UNSIGNED_BYTE, textureData)
        glGenerateMipmap(GL_TEXTURE_2D)
    else:
        print('Failed to load texture')
    del textureData

    vertices = np.array([
         0.5, 0.5, 0,  1, 0, 0,  1, 1,
         0.5,-0.5, 0,  0, 1, 0,  1, 0,
        -0.5,-0.5, 0,  0, 0, 1,  0, 0,
        -0.5, 0.5, 0,  1, 1, 0,  0, 1], dtype = 'float32')
    indices = np.array([0, 1, 3,
                        1, 2, 3], dtype = 'int8')

    shaderProgram = shaderUtils.shader(vert_shader_file, frag_shader_file)
    shaderProgram.compile()

    vbo, vao, ebo = glGenBuffers(1), glGenVertexArrays(1), glGenBuffers(1)

    glBindVertexArray(vao)

    glBindBuffer(GL_ARRAY_BUFFER, vbo)
    glBufferData(GL_ARRAY_BUFFER, vertices, GL_STATIC_DRAW)

    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo)
    glBufferData(GL_ELEMENT_ARRAY_BUFFER, indices, GL_STATIC_DRAW)

    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 32, ctypes.c_void_p(0))
    glEnableVertexAttribArray(0)

    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 32, ctypes.c_void_p(12))
    glEnableVertexAttribArray(1)

    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 32, ctypes.c_void_p(24))
    glEnableVertexAttribArray(2)

    glBindBuffer(GL_ARRAY_BUFFER, 0)
    glBindVertexArray(0)

     while not glfw.window_should_close(window):

        glClearColor(0.2, 0.3, 0.3, 1.0)
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)

        shaderProgram.use()

        glBindTexture(GL_TEXTURE_2D, texture)
        glBindVertexArray(vao)

        glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0)

        glfw.swap_buffers(window)
        glfw.poll_events()

    glDeleteVertexArrays(1, vao)
    glDeleteBuffers(1, vbo)
    glDeleteBuffers(1, ebo)


    glfw.terminate()

if __name__ == '__main__':
    main()

这是我的顶点和片段着色器：

#version 450 core

layout (location = 0) in vec3 aPos;
layout (location = 1) in vec3 aColor;
layout (location = 2) in vec2 aTexCoord;

out vec3 ourColor;
out vec2 TexCoord;

void main() {
    gl_Position = vec4(aPos, 1.0);
    ourColor = aColor;
    TexCoord = aTexCoord;
}

#version 450 core
out vec4 FragColor;

in vec3 ourColor;
in vec2 TexCoord;

uniform sampler2D ourTexture;

void main()
{
    FragColor = texture(ourTexture, TexCoord);
}

我想知道我做错了什么，因为这是我第一次使用 EBO。谢谢！

Answer 1

glDrawElements 的最后一个参数是 const GLvoid * 类型，因此它必须是 None 而不是 0:

~~glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0)~~

glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, None)

此外，索引数组中的数据类型必须与 type 参数对应 glDrawElements.

'int32' 和 GL_UNSIGNED_INT 之一：

indices = np.array([0, 1, 3, 1, 2, 3], dtype = 'int32')

glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, None)

或'int8'和GL_UNSIGNED_BYTE：

indices = np.array([0, 1, 3, 1, 2, 3], dtype = 'int8')

glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_BYTE, None)

当然 'int16' 和 GL_UNSIGNED_SHORT 也可以：

indices = np.array([0, 1, 3, 1, 2, 3], dtype = 'int16')

glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, None)

使用 EBO 时 OpenGL 崩溃

OpenGL crashing when using EBOs

python

ubuntu

opengl

pyopengl