public void updateSelectedOctant(GL gl, GLU glu, float[] mousePosition, float[] pickRectangle) {
// Start Picking mode
int capacity =
1 * 4 * visibleLeaves.size(); // Each object take in maximium : 4 * name stack depth
IntBuffer hitsBuffer = BufferUtil.newIntBuffer(capacity);
gl.glSelectBuffer(hitsBuffer.capacity(), hitsBuffer);
gl.glRenderMode(GL.GL_SELECT);
gl.glDisable(GL.GL_CULL_FACE); // Disable flags
gl.glInitNames();
gl.glPushName(0);
gl.glMatrixMode(GL.GL_PROJECTION);
gl.glPushMatrix();
gl.glLoadIdentity();
glu.gluPickMatrix(
mousePosition[0],
mousePosition[1],
pickRectangle[0],
pickRectangle[1],
drawable.getViewport());
gl.glMultMatrixd(drawable.getProjectionMatrix());
gl.glMatrixMode(GL.GL_MODELVIEW);
// Draw the nodes' cube int the select buffer
int hitName = 1;
for (int i = 0; i < visibleLeaves.size(); i++) {
Octant node = visibleLeaves.get(i);
gl.glLoadName(hitName);
node.displayOctant(gl);
hitName++;
}
// Restoring the original projection matrix
gl.glMatrixMode(GL.GL_PROJECTION);
gl.glPopMatrix();
gl.glMatrixMode(GL.GL_MODELVIEW);
gl.glFlush();
// Returning to normal rendering mode
int nbRecords = gl.glRenderMode(GL.GL_RENDER);
if (vizController.getVizModel().isCulling()) {
gl.glEnable(GL.GL_CULL_FACE);
gl.glCullFace(GL.GL_BACK);
}
// Clean previous selection
selectedLeaves.clear();
// Get the hits and put the node under selection in the selectionArray
for (int i = 0; i < nbRecords; i++) {
int hit = hitsBuffer.get(i * 4 + 3) - 1; // -1 Because of the glPushName(0)
Octant nodeHit = visibleLeaves.get(hit);
selectedLeaves.add(nodeHit);
}
}
