java - 带显示列表的 OpenGL 光照

Question

我正在使用 JOGL 库开发一些 OpenGL 游戏。

当我定期绘制物体时，例如直接在显示方法中使用GL_QUADS，场景照明出现在对象上。

但是，当我在 init 方法中准备对象并在显示列表中使用 glCallList 加载时，这些对象似乎并未受到光照的影响。

准确地说，它们以某种方式受到影响:改变materialfv函数参数或环境参数使场景变亮或变暗，但我尝试扩散的颜色不起作用(仅适用于没有列表的常规绘制对象) )。

代码

这是照明代码:

public void init(GLAutoDrawable drawable) {
    GL2 gl = drawable.getGL().getGL2();

    gl.glShadeModel(GL2.GL_SMOOTH); // Enable Smooth Shading
    gl.glClearColor(0.0f, 0.0f, 0.0f, 0.5f); // Black Background
    gl.glClearDepth(1.0f); // Depth Buffer Setup
    gl.glEnable(GL2.GL_DEPTH_TEST); // Enables Depth Testing
    gl.glDepthFunc(GL2.GL_LEQUAL); // The Type Of Depth Testing To Do
    glu = new GLU();
    // Really Nice Perspective Calculations
    gl.glHint(GL2.GL_PERSPECTIVE_CORRECTION_HINT, GL2.GL_NICEST);

    // Light
    float   ambient[] = {0.1f,0.1f,0.1f,1.0f};
    float   diffuse0[] = {1f,0f,0f,1.0f};
    float   diffuse1[] = {0f,0f,1f,1.0f};

    gl.glShadeModel(GL2.GL_SMOOTH); 

    gl.glLightfv(GL2.GL_LIGHT0, GL2.GL_AMBIENT, ambient, 0);
    gl.glLightfv(GL2.GL_LIGHT0, GL2.GL_DIFFUSE, diffuse0, 0);
    gl.glEnable(GL2.GL_LIGHT0);

    gl.glLightfv(GL2.GL_LIGHT1, GL2.GL_AMBIENT, ambient, 0);
    gl.glLightfv(GL2.GL_LIGHT1, GL2.GL_DIFFUSE, diffuse1, 0);
    gl.glEnable(GL2.GL_LIGHT1);

    gl.glEnable(GL2.GL_LIGHTING);

    // make display lists here...

显示屏灯光部分:

// display method...
// apply light
float position0[] = {500, 300, 3500,1.0f};
float position1[] = {500, 300, 500,1.0f};
gl.glLightfv(GL2.GL_LIGHT0, GL2.GL_POSITION, position0, 0);
gl.glLightfv(GL2.GL_LIGHT1, GL2.GL_POSITION, position1, 0);
// draw objects directly
// draw objects using glCallLists

以下是我如何在显示方法中绘制常规对象的示例:

gl.glPushMatrix();
    gl.glTranslatef(1000, 500, 2000);
    gl.glTexParameteri ( GL.GL_TEXTURE_2D,GL.GL_TEXTURE_WRAP_T, GL.GL_REPEAT );
    gl.glTexParameteri( GL.GL_TEXTURE_2D,GL.GL_TEXTURE_WRAP_S, GL.GL_REPEAT );
    float   material[] = {0.8f,0.8f,0.8f,1.0f};
    gl.glMaterialfv(GL2.GL_FRONT_AND_BACK, GL2.GL_AMBIENT_AND_DIFFUSE, material, 0);
    gl.glBegin(GL2.GL_QUADS);
    // Front Face
    gl.glNormal3f(0,0,1);
    gl.glTexCoord2f(0.0f, 0.0f);
    gl.glVertex3f(-1.0f, -1.0f, 1.0f);
    gl.glTexCoord2f(2f, 0.0f);
    gl.glVertex3f(1.0f, -1.0f, 1.0f);
    gl.glTexCoord2f(2f, 1.0f);
    gl.glVertex3f(1.0f, 1.0f, 1.0f);
    gl.glTexCoord2f(0.0f, 1.0f);
    gl.glVertex3f(-1.0f, 1.0f, 1.0f);
    // Back Face
    gl.glNormal3f(0,0,-1);
    gl.glTexCoord2f(1.0f, 0.0f);
    gl.glVertex3f(-1.0f, -1.0f, -1.0f);
    gl.glTexCoord2f(1.0f, 1.0f);
    gl.glVertex3f(-1.0f, 1.0f, -1.0f);
    gl.glTexCoord2f(0.0f, 1.0f);
    gl.glVertex3f(1.0f, 1.0f, -1.0f);
    gl.glTexCoord2f(0.0f, 0.0f);
    gl.glVertex3f(1.0f, -1.0f, -1.0f);
    // Top Face
    gl.glNormal3f(0,1,0);
    gl.glTexCoord2f(0.0f, 1.0f);
    gl.glVertex3f(-1.0f, 1.0f, -1.0f);
    gl.glTexCoord2f(0.0f, 0.0f);
    gl.glVertex3f(-1.0f, 1.0f, 1.0f);
    gl.glTexCoord2f(1.0f, 0.0f);
    gl.glVertex3f(1.0f, 1.0f, 1.0f);
    gl.glTexCoord2f(1.0f, 1.0f);
    gl.glVertex3f(1.0f, 1.0f, -1.0f);
    // Bottom Face
    gl.glNormal3f(0,-1,0);
    gl.glTexCoord2f(1.0f, 1.0f);
    gl.glVertex3f(-1.0f, -1.0f, -1.0f);
    gl.glTexCoord2f(0.0f, 1.0f);
    gl.glVertex3f(1.0f, -1.0f, -1.0f);
    gl.glTexCoord2f(0.0f, 0.0f);
    gl.glVertex3f(1.0f, -1.0f, 1.0f);
    gl.glTexCoord2f(1.0f, 0.0f);
    gl.glVertex3f(-1.0f, -1.0f, 1.0f);
    // Right face
    gl.glNormal3f(1,0,0);
    gl.glTexCoord2f(1.0f, 0.0f);
    gl.glVertex3f(1.0f, -1.0f, -1.0f);
    gl.glTexCoord2f(1.0f, 1.0f);
    gl.glVertex3f(1.0f, 1.0f, -1.0f);
    gl.glTexCoord2f(0.0f, 1.0f);
    gl.glVertex3f(1.0f, 1.0f, 1.0f);
    gl.glTexCoord2f(0.0f, 0.0f);
    gl.glVertex3f(1.0f, -1.0f, 1.0f);
    // Left Face
    gl.glNormal3f(-1,0,0);
    gl.glTexCoord2f(0.0f, 0.0f);
    gl.glVertex3f(-1.0f, -1.0f, -1.0f);
    gl.glTexCoord2f(1.0f, 0.0f);
    gl.glVertex3f(-1.0f, -1.0f, 1.0f);
    gl.glTexCoord2f(1.0f, 1.0f);
    gl.glVertex3f(-1.0f, 1.0f, 1.0f);
    gl.glTexCoord2f(0.0f, 1.0f);
    gl.glVertex3f(-1.0f, 1.0f, -1.0f);
    gl.glEnd();
    gl.glPopMatrix(); 

Here's the class I use to load obj files.

我使用 loadWavefrontObjectAsDisplayList 方法，该方法接受 obj 文件的路径，然后返回列表整数。

另一个编辑:

场景(灯被点亮， crate 没有点亮):

Link to lamp and crate .obj files.

Answer 1

crate 模型的 WaveFront OBJ 文件中可能缺少法线。

然后，您使用的 OBJ 导入器会生成错误的法线，其坐标为 (0, 0, 0)，它没有机会处理闪电。