/*
* Copyright (C) 2015 Jorge Ruesga
*
*
* 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.
*/
//
// Based on the shaders of kodemongki:
// http://kodemongki.blogspot.com.es/2011/06/kameraku-custom-shader-effects-example.html
//
package com.ruesga.android.wallpapers.photophase.effects;
import android.media.effect.EffectContext;
import android.opengl.GLES20;
import android.util.Log;
import com.ruesga.android.wallpapers.photophase.utils.GLESUtil;
/**
* A noise effect<br/>
* <table>
* <tr><td>Parameter name</td><td>Meaning</td><td>Valid values</td></tr>
* </table>
*/
public class NoiseEffect extends PhotoPhaseEffect {
private static final String TAG = "NoiseEffect";
public static final String STRENGTH_PARAMETER = "strength";
private static final String FRAGMENT_SHADER =
"precision mediump float;\n" +
"uniform sampler2D tex_sampler;\n" +
"varying vec2 v_texcoord;\n" +
"uniform float strength;\n" +
"void main(void)\n" +
"{\n" +
" vec2 uv = v_texcoord;\n" +
" vec3 c1 = texture2D(tex_sampler, vec2(uv.s - strength, uv.t - strength)).bgr;\n" +
" vec3 c2 = texture2D(tex_sampler, vec2(uv.s + strength, uv.t + strength)).bgr;\n" +
" vec3 c3 = texture2D(tex_sampler, vec2(uv.s - strength, uv.t + strength)).bgr;\n" +
" vec3 c4 = texture2D(tex_sampler, vec2(uv.s + strength, uv.t - strength)).bgr;\n" +
" gl_FragColor.a = 1.0;\n" +
" gl_FragColor.rgb = (c1 + c2 + c3 + c4) / 4.0;\n" +
"}";
private float mStrength = 0.02f;
private final int mStrengthHandle;
/**
* Constructor of <code>NoiseEffect</code>.
*
* @param ctx The effect context
* @param name The effect name
*/
public NoiseEffect(EffectContext ctx, String name) {
super(ctx, NoiseEffect.class.getName());
init(VERTEX_SHADER, FRAGMENT_SHADER);
// Parameters
mStrengthHandle = GLES20.glGetUniformLocation(mProgram[0], "strength");
GLESUtil.glesCheckError("glGetUniformLocation");
}
/**
* {@inheritDoc}
*/
@Override
void applyParameters(int width, int height) {
// Set parameters
GLES20.glUniform1f(mStrengthHandle, mStrength);
GLESUtil.glesCheckError("glUniform1f");
}
/**
* {@inheritDoc}
*/
@Override
public void setParameter(String parameterKey, Object value) {
if (parameterKey.compareTo(STRENGTH_PARAMETER) == 0) {
try {
float strength = Float.parseFloat(value.toString());
if (strength < 0) {
Log.w(TAG, "strength parameter must be > 0");
return;
}
mStrength = strength;
} catch (NumberFormatException ex) {
// Ignore
}
}
}
}