com.ardor3d.scene.state.lwjgl.LwjglZBufferStateUtil.java Source code

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Here is the source code for com.ardor3d.scene.state.lwjgl.LwjglZBufferStateUtil.java

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/**
 * Copyright (c) 2008-2012 Ardor Labs, Inc.
 *
 * This file is part of Ardor3D.
 *
 * Ardor3D is free software: you can redistribute it and/or modify it 
 * under the terms of its license which may be found in the accompanying
 * LICENSE file or at <http://www.ardor3d.com/LICENSE>.
 */

package com.ardor3d.scene.state.lwjgl;

import org.lwjgl.opengl.GL11;

import com.ardor3d.renderer.ContextManager;
import com.ardor3d.renderer.RenderContext;
import com.ardor3d.renderer.state.RenderState.StateType;
import com.ardor3d.renderer.state.ZBufferState;
import com.ardor3d.renderer.state.record.ZBufferStateRecord;

public abstract class LwjglZBufferStateUtil {

    public static void apply(final ZBufferState state) {
        // ask for the current state record
        final RenderContext context = ContextManager.getCurrentContext();
        final ZBufferStateRecord record = (ZBufferStateRecord) context.getStateRecord(StateType.ZBuffer);
        context.setCurrentState(StateType.ZBuffer, state);

        enableDepthTest(state.isEnabled(), record);
        if (state.isEnabled()) {
            int depthFunc = 0;
            switch (state.getFunction()) {
            case Never:
                depthFunc = GL11.GL_NEVER;
                break;
            case LessThan:
                depthFunc = GL11.GL_LESS;
                break;
            case EqualTo:
                depthFunc = GL11.GL_EQUAL;
                break;
            case LessThanOrEqualTo:
                depthFunc = GL11.GL_LEQUAL;
                break;
            case GreaterThan:
                depthFunc = GL11.GL_GREATER;
                break;
            case NotEqualTo:
                depthFunc = GL11.GL_NOTEQUAL;
                break;
            case GreaterThanOrEqualTo:
                depthFunc = GL11.GL_GEQUAL;
                break;
            case Always:
                depthFunc = GL11.GL_ALWAYS;
            }
            applyFunction(depthFunc, record);
        }

        enableWrite(state.isWritable(), record);

        if (!record.isValid()) {
            record.validate();
        }
    }

    private static void enableDepthTest(final boolean enable, final ZBufferStateRecord record) {
        if (enable && (!record.depthTest || !record.isValid())) {
            GL11.glEnable(GL11.GL_DEPTH_TEST);
            record.depthTest = true;
        } else if (!enable && (record.depthTest || !record.isValid())) {
            GL11.glDisable(GL11.GL_DEPTH_TEST);
            record.depthTest = false;
        }
    }

    private static void applyFunction(final int depthFunc, final ZBufferStateRecord record) {
        if (depthFunc != record.depthFunc || !record.isValid()) {
            GL11.glDepthFunc(depthFunc);
            record.depthFunc = depthFunc;
        }
    }

    private static void enableWrite(final boolean enable, final ZBufferStateRecord record) {
        if (enable != record.writable || !record.isValid()) {
            GL11.glDepthMask(enable);
            record.writable = enable;
        }
    }
}