java - LWJGL:渲染天空盒的更有效方法

Question

我目前正在渲染一个天空盒，如下所示:

        //Front Face
    GL11.glBindTexture(GL11.GL_TEXTURE_2D, skybox[0].getTextureID());
    GL11.glBegin(GL11.GL_QUADS);
        GL11.glTexCoord2f(1f, 0.0f);
        GL11.glVertex3f(-player.x - offset, -player.y - offset, -player.z - offset);
        GL11.glTexCoord2f(1f, 1f);
        GL11.glVertex3f(-player.x - offset, -player.y + offset, -player.z - offset);
        GL11.glTexCoord2f(0.0f, 1f);
        GL11.glVertex3f(-player.x + offset, -player.y + offset, -player.z - offset);
        GL11.glTexCoord2f(0.0f, 0.0f);
        GL11.glVertex3f(-player.x + offset, -player.y - offset, -player.z - offset);
    GL11.glEnd();

    // Back Face
    GL11.glBindTexture(GL11.GL_TEXTURE_2D, skybox[2].getTextureID());
    GL11.glBegin(GL11.GL_QUADS);
        GL11.glTexCoord2f(0.0f, 0.0f);
        GL11.glVertex3f(-player.x - offset, -player.y - offset, -player.z + offset);
        GL11.glTexCoord2f(1f, 0.0f);
        GL11.glVertex3f(-player.x + offset, -player.y - offset, -player.z + offset);
        GL11.glTexCoord2f(1f, 1f);
        GL11.glVertex3f(-player.x + offset, -player.y + offset, -player.z + offset);
        GL11.glTexCoord2f(0.0f, 1f);
        GL11.glVertex3f(-player.x - offset, -player.y + offset, -player.z + offset);
    GL11.glEnd();

    // Top Face
    GL11.glBindTexture(GL11.GL_TEXTURE_2D, skybox[4].getTextureID());
    GL11.glBegin(GL11.GL_QUADS);
        GL11.glTexCoord2f(1f, 1f);
        GL11.glVertex3f(-player.x - offset, -player.y - offset, -player.z - offset);
        GL11.glTexCoord2f(0.0f, 1f);
        GL11.glVertex3f(-player.x + offset, -player.y - offset, -player.z - offset);
        GL11.glTexCoord2f(0.0f, 0.0f);
        GL11.glVertex3f(-player.x + offset, -player.y - offset, -player.z + offset);
        GL11.glTexCoord2f(1f, 0.0f);
        GL11.glVertex3f(-player.x - offset, -player.y - offset, -player.z + offset);
    GL11.glEnd();

    // Bottom Face
    GL11.glBindTexture(GL11.GL_TEXTURE_2D, skybox[5].getTextureID());
    GL11.glBegin(GL11.GL_QUADS);
        GL11.glTexCoord2f(1f, 0f);
        GL11.glVertex3f(-player.x - offset, -player.y + offset, -player.z - offset);
        GL11.glTexCoord2f(1f, 1f);
        GL11.glVertex3f(-player.x - offset, -player.y + offset, -player.z + offset);
        GL11.glTexCoord2f(0f, 1f);
        GL11.glVertex3f(-player.x + offset, -player.y + offset, -player.z + offset);
        GL11.glTexCoord2f(0f, 0f);
        GL11.glVertex3f(-player.x + offset, -player.y + offset, -player.z - offset);
    GL11.glEnd();


    // Right face
    GL11.glBindTexture(GL11.GL_TEXTURE_2D, skybox[3].getTextureID());
    GL11.glBegin(GL11.GL_QUADS);
        GL11.glTexCoord2f(0.0f, 0.0f);
        GL11.glVertex3f(-player.x - offset, -player.y - offset, -player.z - offset);
        GL11.glTexCoord2f(1f, 0.0f);
        GL11.glVertex3f(-player.x - offset, -player.y - offset, -player.z + offset);
        GL11.glTexCoord2f(1f, 1f);
        GL11.glVertex3f(-player.x - offset, -player.y + offset, -player.z + offset);
        GL11.glTexCoord2f(0.0f, 1f);
        GL11.glVertex3f(-player.x - offset, -player.y + offset, -player.z - offset);
    GL11.glEnd();

    // Left Face
    GL11.glBindTexture(GL11.GL_TEXTURE_2D, skybox[1].getTextureID());
    GL11.glBegin(GL11.GL_QUADS);
        GL11.glTexCoord2f(1f, 0.0f);
        GL11.glVertex3f(-player.x + offset, -player.y - offset, -player.z - offset);
        GL11.glTexCoord2f(1f, 1f);
        GL11.glVertex3f(-player.x + offset, -player.y + offset, -player.z - offset);
        GL11.glTexCoord2f(0.0f, 1f);
        GL11.glVertex3f(-player.x + offset, -player.y + offset, -player.z + offset);
        GL11.glTexCoord2f(0.0f, 0.0f);
        GL11.glVertex3f(-player.x + offset, -player.y - offset, -player.z + offset);
    GL11.glEnd();

这似乎是渲染天空盒的一种极其低效的方法，因为我必须不断在纹理和四边形之间切换。此外，像这样渲染四边形往往会归因于视觉伪像，例如单像素线(四边形之间的接缝)。我听说过利用立方体贴图来提高效率，但在实现过程中遇到了困难。如果你们有任何建议，请随时为我指出正确的方向。谢谢。

Answer 1

立方体贴图基本上是将所有六个纹理放在一个纹理上。然后仅更改一次坐标并使用一次 glBindTexture 这将类似于:

GL11.glBindTexture(GL11.GL_TEXTURE_2D, skybox.getTextureID());
GL11.glBegin(GL11.GL_QUADS);
    //Front Face
    GL11.glTexCoord2f(0.25f, 0.25f);
    GL11.glVertex3f(-player.x - offset, -player.y - offset, -player.z - offset);
    GL11.glTexCoord2f(0.25f, 0.5f);
    GL11.glVertex3f(-player.x - offset, -player.y + offset, -player.z - offset);
    GL11.glTexCoord2f(0.0f, 0.5f);
    GL11.glVertex3f(-player.x + offset, -player.y + offset, -player.z - offset);
    GL11.glTexCoord2f(0.0f, 0.25f);
    GL11.glVertex3f(-player.x + offset, -player.y - offset, -player.z - offset);

    // Back Face
    ...
GL11.glEnd();

为了获得更多优化，请考虑在渲染天空盒时禁用深度缓冲区。您也可以停止清除颜色位。