Question

我目前正在使用VBO在OpenGL中使用GLSL着色器绘制一系列立方体，该着色器执行多纹理（具有5个纹理）。如果我不传递纹理，它工作正常。但如果我尝试使用纹理，整个屏幕只画出白色（大概是最后一个清晰的颜色）。如果我使用立即模式（没有VBO）传递纹理，那么它也很好。我不知道为什么会有问题。

代码：

// create vertex/normal/color/texcoord VBO
glGenBuffersARB(1, &vboId);
glBindBufferARB(GL_ARRAY_BUFFER_ARB, vboId);
glBufferDataARB(GL_ARRAY_BUFFER_ARB, sizeof(vert_buf)+sizeof(norm_buf)+sizeof(col_buf)+sizeof(tex_buf), 0, GL_STREAM_DRAW);
glBufferSubDataARB(GL_ARRAY_BUFFER_ARB, 0, sizeof(vert_buf), vert_buf);
glBufferSubDataARB(GL_ARRAY_BUFFER_ARB, sizeof(vert_buf), sizeof(norm_buf), norm_buf);
glBufferSubDataARB(GL_ARRAY_BUFFER_ARB, sizeof(vert_buf)+sizeof(norm_buf), sizeof(col_buf), col_buf);
glBufferSubDataARB(GL_ARRAY_BUFFER_ARB, sizeof(vert_buf)+sizeof(norm_buf)+sizeof(col_buf), sizeof(tex_buf), tex_buf);
glBindBufferARB(GL_ARRAY_BUFFER_ARB, 0);

// create geometry indices VBO
glGenBuffersARB(1, &vboId2);
glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, vboId2);
glBufferDataARB(GL_ELEMENT_ARRAY_BUFFER_ARB, sizeof(index_buf), index_buf, GL_STATIC_DRAW_ARB);
glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, 0);

// bind vertex/normal/color/texcoord VBO
glBindBufferARB(GL_ARRAY_BUFFER_ARB, vboId);

// enable vertex arrays
glEnableClientState(GL_NORMAL_ARRAY);
glEnableClientState(GL_COLOR_ARRAY);
glEnableClientState(GL_VERTEX_ARRAY);

// specify vertex and index arrays with their offsets
glVertexPointer(3, GL_FLOAT, 0, 0);
glNormalPointer(GL_FLOAT, 0, (void*)sizeof(vert_buf));
glColorPointer(3, GL_FLOAT, 0, (void*)(sizeof(vert_buf)+sizeof(norm_buf)));

// bind geometry indices VBO
glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, vboId2);
glIndexPointer(GL_UNSIGNED_INT, 0, 0);

// set the texture units
GLvoid* start = (void*)(sizeof(vert_buf)+sizeof(norm_buf)+sizeof(col_buf));
glClientActiveTexture(GL_TEXTURE0 + (GLuint)vid_regions[0].tex_id); // same as GL_TEXTURE1
glTexCoordPointer(2, GL_FLOAT, 0, start);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glClientActiveTexture(GL_TEXTURE0 + (GLuint)vid_regions[1].tex_id); // same as GL_TEXTURE2
glTexCoordPointer(2, GL_FLOAT, 0, start);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glClientActiveTexture(GL_TEXTURE0 + (GLuint)vid_regions[2].tex_id); // same as GL_TEXTURE3
glTexCoordPointer(2, GL_FLOAT, 0, start);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glClientActiveTexture(GL_TEXTURE0 + noiseTexID);    // same as GL_TEXTURE4
glTexCoordPointer(2, GL_FLOAT, 0, start);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glClientActiveTexture(GL_TEXTURE0 + lutTexID);  // same as GL_TEXTURE5
glTexCoordPointer(2, GL_FLOAT, 0, start);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);

// draw VBOs
glDrawElements(GL_TRIANGLES, 36*ROWS*COLS, GL_UNSIGNED_INT, 0);

// disable arrays
glDisableClientState(GL_VERTEX_ARRAY);
glDisableClientState(GL_COLOR_ARRAY);
glDisableClientState(GL_NORMAL_ARRAY);

// disable texture arrays
glClientActiveTexture(GL_TEXTURE0 + (GLuint)vid_regions[0].tex_id);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
glClientActiveTexture(GL_TEXTURE0 + (GLuint)vid_regions[1].tex_id);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
glClientActiveTexture(GL_TEXTURE0 + (GLuint)vid_regions[2].tex_id);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
glClientActiveTexture(GL_TEXTURE0 + noiseTexID);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
glClientActiveTexture(GL_TEXTURE0 + lutTexID);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);

// unbind VBOs
glBindBufferARB(GL_ARRAY_BUFFER_ARB, 0);
glBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, 0);

注意：在初始设置阶段调用VBO的创建。绘图发生在绘图GLUT例程中。

Answer 1

尝试将纹理级别重置为0：

glClientActiveTexture(GL_TEXTURE0);

当活动纹理级别未重置时（例如，如果您正在使用FBO等），发生奇怪现象的情况并不少见。

将清晰的颜色设置为黑/白/透明以外的其他颜色也可能会有所帮助，以查看是否使用清晰的颜色绘制屏幕，或者您是否以某种方式看到拉伸纹理或其他东西。

具有多纹理问题的OpenGL VBO绘图

1 个答案: