/*
* This file is part of the Illarion project.
*
* Copyright © 2014 - Illarion e.V.
*
* Illarion is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Illarion is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
package org.illarion.engine.backend.gdx;
import com.badlogic.gdx.Files;
import com.badlogic.gdx.graphics.g2d.SpriteBatch;
import com.badlogic.gdx.graphics.glutils.ShaderProgram;
import org.illarion.engine.graphic.effects.FogEffect;
import javax.annotation.Nonnull;
/**
* The libGDX implementation of the fog effect.
*
* @author Martin Karing <nitram@illarion.org>
*/
class GdxFogEffect implements FogEffect, GdxSceneEffect {
/**
* The pixel shader that is required for this effect.
*/
@Nonnull
private final ShaderProgram shader;
/**
* The density that was applied last.
*/
private float density;
GdxFogEffect(@Nonnull Files files) {
//noinspection SpellCheckingInspection
shader = new ShaderProgram(files.internal("org/illarion/engine/backend/gdx/shaders/generic.vert"),
files.internal("org/illarion/engine/backend/gdx/shaders/fog.frag"));
}
@Override
public void setDensity(float density) {
this.density = density;
}
@Override
public void update(int delta) {
// nothing to do
}
@Override
public void activateEffect(
@Nonnull SpriteBatch batch, int screenWidth, int screenHeight, int textureWidth, int textureHeight) {
batch.setShader(shader);
shader.setUniformf("u_density", density);
shader.setUniformf("u_center", screenWidth / 2.f / textureWidth, screenHeight / 2.f / textureHeight);
}
@Override
public void disableEffect(@Nonnull SpriteBatch batch) {
batch.setShader(null);
}
}