[OPENGL,LWJGL] LWJGL 이동과 회전 그리고 픽킹(LWJGL - Rotation and Picking)

public void SelectObjects(int x, int y) {

int hits;

int[] viewport = new int[4];

int buffer[] = new int[256];

IntBuffer selectBuff = ByteBuffer.allocateDirect(1024).order(ByteOrder.nativeOrder()).asIntBuffer();

IntBuffer vpBuffer = ByteBuffer.allocateDirect(64).order(ByteOrder.nativeOrder()).asIntBuffer();

GL11.glGetInteger(GL11.GL_VIEWPORT, vpBuffer);

vpBuffer.get(viewport);

GL11.glSelectBuffer(selectBuff);

GL11.glMatrixMode(GL11.GL_PROJECTION);

GL11.glPushMatrix();

GL11.glRenderMode(GL11.GL_SELECT);

GL11.glLoadIdentity();

GLU.gluPickMatrix((float)x,(float)(viewport[3]-y), 5.0f, 5.0f, viewport);

GLU.gluPerspective(45.0f, ratio, 0.001f, 100.0f);

//Rectangle rect = this.canvas.getClientArea();

// ratio = (float) rect.width / (float) rect.height;

GL11.glMatrixMode(GL11.GL_MODELVIEW); // 물체를 그려줄때는 다시 모델뷰로..

drawScatterPlot();                                  // 물체를 그려주고,

GL11.glRotatef(this.xrot, 1.0f, 0.0f, 0.0f);  // 그 후에 회전을 해준다.

GL11.glRotatef(this.yrot, 0.0f, 1.0f, 0.0f);

hits = GL11.glRenderMode(GL11.GL_RENDER);

System.out.println("Hits : "+hits);

selectBuff.get(buffer);

if(hits>0) {

int selectedObjID = buffer[3];

int depth = buffer[1];

for (int i = 1; i < hits; i++) {

if (buffer[i * 4 + 1] < (int) depth) {

selectedObjID = buffer[i * 4 + 3];

depth = buffer[i * 4 + 1];

}

}

ProcessSelect(selectedObjID);

}

GL11.glMatrixMode(GL11.GL_PROJECTION);

GL11.glPopMatrix();

GL11.glFlush();

GL11.glMatrixMode(GL11.GL_MODELVIEW);

}