glbuffersubdata不起作用，不显示错误

Question

我正在使用GLFW使用Python进行基本的Voxel渲染课。我正在使用 glbuffersubdata 而不是 glbufferdata ，但不会呈现。这是怀疑引起问题的代码：

# imports
import glfw, numpy as np
from OpenGL.GL import *
from ctypes import *
from core.texture_manager import *

glfw.init()

class VBOManager:
    def __init__(self, renderer):
        self.renderer = renderer
        self.run()
    
    def run(self):
        for i in self.renderer.to_add[:self.renderer.to_add_count]:
            self.renderer.vertices.extend(i[0])
            self.renderer.texCoords.extend(i[1])
            vertices = np.array(i[0], dtype=np.float32)
            texCoords = np.array(i[1], dtype=np.float32)

            # use glBufferSubData
            glBindBuffer(GL_ARRAY_BUFFER, self.renderer.vbo)
            glBufferData(GL_ARRAY_BUFFER, self.renderer.vertices.nbytes, vertices.nbytes, (c_float * len(vertices))(*vertices))
            glFlush()
            glVertexPointer(3, GL_FLOAT, 0, None)
            glTexCoordPointer(3, GL_FLOAT, 0, None)
            glBindBuffer(GL_ARRAY_BUFFER, self.renderer.vbo_1)
            glBufferSubData(GL_ARRAY_BUFFER, self.renderer.texCoords.nbytes, texCoords.nbytes, (c_float * len(texCoords))(*texCoords))
            glFlush()

            self.renderer.to_add.remove(i)

class TerrainRenderer:
    def __init__(self, window):
        self.window = window

        self.vertices = np.array([])
        self.texCoords = np.array([])

        self.to_add = []
        self.to_add_count = 256

        self.vbo, self.vbo_1 = glGenBuffers (2)
        glBindBuffer(GL_ARRAY_BUFFER, self.vbo)
        glBufferData(GL_ARRAY_BUFFER, 12 * 4, None, GL_STATIC_DRAW)
        self.vbo_manager = VBOManager(self)

        self.texture_manager = TextureAtlas()

        glEnable(GL_TEXTURE_2D)
        glEnable(GL_BLEND)
        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)
        glEnableClientState(GL_TEXTURE_COORD_ARRAY)
        glEnableClientState (GL_VERTEX_ARRAY)

    def render(self):
        try:
            self.vbo_manager.run()
        except RuntimeError:
            pass

        glClear (GL_COLOR_BUFFER_BIT)

        glEnable(GL_TEXTURE_2D)
        glEnable(GL_BLEND)
        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA)
        glBindBuffer (GL_ARRAY_BUFFER, self.vbo)
        glVertexPointer (3, GL_FLOAT, 0, None)
        glBindBuffer(GL_ARRAY_BUFFER, self.vbo_1)
        glTexCoordPointer(2, GL_FLOAT, 0, None)

        glDrawArrays (GL_QUADS, 0, len(self.vertices))
        glDisable(GL_TEXTURE_2D)
        glDisable(GL_BLEND)

    def add(self, posList, texCoords):
        self.to_add.append((numpy.array(posList), numpy.array(texCoords)))

当我启动使用此代码的应用程序时，它没有显示日志，警告或错误，但也根本不会呈现顶点。屏幕上什么都看不见。

Answer 1

，之后，您可以使用 glbuffersubdata 更新数据。此外， glbuffersubdata的第二个参数将偏移量指定为启动数据更换的缓冲区对象的数据存储。

glBindBuffer(GL_ARRAY_BUFFER, self.vbo_1)
glBufferData(GL_ARRAY_BUFFER, texCoords.nbytes, None, GL_STATIC_DRAW)

glBindBuffer(GL_ARRAY_BUFFER, self.renderer.vbo_1)
glBufferSubData(GL_ARRAY_BUFFER, 0, texCoords.nbytes, (c_float * len(texCoords))(*texCoords))