/*******************************************************************************
* Copyright 2012 Geoscience Australia
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
******************************************************************************/
package au.gov.ga.earthsci.worldwind.common.layers.transform;
import gov.nasa.worldwind.geom.Matrix;
import gov.nasa.worldwind.layers.SkyGradientLayer;
import gov.nasa.worldwind.render.DrawContext;
import gov.nasa.worldwind.util.OGLStackHandler;
import javax.media.opengl.GL2;
import au.gov.ga.earthsci.worldwind.common.view.delegate.IDelegateView;
/**
* An extension of the {@link SkyGradientLayer} that, if the view is a
* {@link TransformView}, correctly calculates the projection matrix so that the
* sky gradient is correctly offset for the transformed projection matrix.
*/
public class TransformSkyGradientLayer extends SkyGradientLayer
{
@Override
protected void applyDrawProjection(DrawContext dc, OGLStackHandler ogsh)
{
boolean loaded = false;
if (dc.getView() instanceof IDelegateView)
{
IDelegateView transform = (IDelegateView) dc.getView();
//near is the distance from the origin
double near = 100;
double far = transform.getHorizonDistance() + 10e3;
Matrix projection = transform.computeProjection(near, far);
if (projection != null)
{
double[] matrixArray = new double[16];
GL2 gl = dc.getGL().getGL2();
ogsh.pushProjection(gl);
projection.toArray(matrixArray, 0, false);
gl.glLoadMatrixd(matrixArray, 0);
loaded = true;
}
}
if (!loaded)
{
super.applyDrawProjection(dc, ogsh);
}
}
}