/*******************************************************************************
* Copyright 2011 See AUTHORS file.
*
* 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 com.badlogic.gdx.tests;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.graphics.GL20;
import com.badlogic.gdx.graphics.Mesh;
import com.badlogic.gdx.graphics.OrthographicCamera;
import com.badlogic.gdx.graphics.Pixmap.Format;
import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.VertexAttribute;
import com.badlogic.gdx.graphics.VertexAttributes.Usage;
import com.badlogic.gdx.graphics.glutils.FloatFrameBuffer;
import com.badlogic.gdx.graphics.glutils.FrameBuffer;
import com.badlogic.gdx.graphics.glutils.ShaderProgram;
import com.badlogic.gdx.math.Vector3;
import com.badlogic.gdx.tests.utils.GdxTest;
public class FloatTextureTest extends GdxTest {
FrameBuffer fb;
FloatFrameBuffer ffb;
ShaderProgram fbshader, shader;
Texture texture;
Mesh quad, screenQuad;
OrthographicCamera screenCamera;
@Override
public void create () {
fb = new FrameBuffer(Format.RGBA8888, 200, 100, false);
ffb = new FloatFrameBuffer(200, 100, false);
// @off
String vertexShader =
"attribute vec4 a_position; "
+ "varying vec2 v_position; "
+ "void main(){ "
+ " v_position = a_position.xy; "
+ " gl_Position = vec4(a_position.x, a_position.y, 0.0, 1.0); "
+ "}";
String fragmentShader =
"#ifdef GL_ES\n"
+ "precision mediump float;\n"
+ "#endif\n" + "uniform vec3 u_color;"
+ "uniform vec2 u_viewport; "
+ "void main(void){ "
+ " vec2 uv = gl_FragCoord.xy/u_viewport; "
+ " float res = mix(0.0, 0.0001, uv.x); " // <--- // regular (non-float) texture loses precision here, res == 0 for every fragment
+ " gl_FragColor = vec4(u_color, res); "
+ "}";
fbshader = new ShaderProgram(vertexShader, fragmentShader);
vertexShader =
"attribute vec4 a_position; "
+ "attribute vec4 a_color; "
+ "attribute vec2 a_texCoords; "
+ "uniform mat4 u_worldView; "
+ "varying vec4 v_color; "
+ "varying vec2 v_texCoords; "
+ "void main() "
+ "{ "
+ " v_color = a_color; "
+ " v_texCoords = a_texCoords; "
+ " gl_Position = u_worldView * a_position; "
+ "}";
fragmentShader =
"#ifdef GL_ES\n"
+ "precision mediump float;\n"
+ "#endif\n"
+ "varying vec2 v_texCoords; "
+ "uniform sampler2D u_fbtex, u_ffbtex; "
+ "vec4 getValue(vec4 col) {"
+ " if (col.a > 0.00005)"
+ " return vec4(col.rgb, 1.0);"
+ " else"
+ " return vec4(0.0, 0.0, 0.0, 1.0);"
+ "}"
+ "void main() "
+ "{ "
+ " if (v_texCoords.y < 0.45)"
+ " gl_FragColor = getValue(texture2D(u_fbtex, v_texCoords)); "
+ " else if (v_texCoords.y > 0.55)"
+ " gl_FragColor = getValue(texture2D(u_ffbtex, v_texCoords)); "
+ "}";
// @on
shader = new ShaderProgram(vertexShader, fragmentShader);
createQuad();
screenCamera = new OrthographicCamera(Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
createScreenQuad();
}
public void render () {
Gdx.gl20.glViewport(0, 0, Gdx.graphics.getBackBufferWidth(), Gdx.graphics.getBackBufferHeight());
Gdx.gl20.glClear(GL20.GL_COLOR_BUFFER_BIT);
fb.begin();
fbshader.begin();
fbshader.setUniformf("u_viewport", fb.getWidth(), fb.getHeight());
fbshader.setUniformf("u_color", 0.0f, 1.0f, 0.0f);
quad.render(fbshader, GL20.GL_TRIANGLES);
fbshader.end();
fb.end();
ffb.begin();
fbshader.begin();
fbshader.setUniformf("u_viewport", ffb.getWidth(), ffb.getHeight());
fbshader.setUniformf("u_color", 1.0f, 0.0f, 0.0f);
quad.render(fbshader, GL20.GL_TRIANGLES);
fbshader.end();
ffb.end();
shader.begin();
fb.getColorBufferTexture().bind(0);
ffb.getColorBufferTexture().bind(1);
shader.setUniformMatrix("u_worldView", screenCamera.combined);
shader.setUniformi("u_fbtex", 0);
shader.setUniformi("u_ffbtex", 1);
screenQuad.render(shader, GL20.GL_TRIANGLES);
shader.end();
}
private void createQuad () {
if (quad != null) return;
quad = new Mesh(true, 4, 6, new VertexAttribute(Usage.Position, 3, "a_position"), new VertexAttribute(Usage.ColorUnpacked, 4,
"a_color"), new VertexAttribute(Usage.TextureCoordinates, 2, "a_texCoords"));
quad.setVertices(new float[] {-1, -1, 0, 1, 1, 1, 1, 0, 1, 1, -1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, -1, 1, 0,
1, 1, 1, 1, 0, 0});
quad.setIndices(new short[] {0, 1, 2, 2, 3, 0});
}
private void createScreenQuad () {
if (screenQuad != null) return;
screenQuad = new Mesh(true, 4, 6, new VertexAttribute(Usage.Position, 3, "a_position"), new VertexAttribute(Usage.ColorUnpacked, 4,
"a_color"), new VertexAttribute(Usage.TextureCoordinates, 2, "a_texCoords"));
Vector3 vec0 = new Vector3(0, 0, 0);
screenCamera.unproject(vec0);
Vector3 vec1 = new Vector3(Gdx.graphics.getWidth(), Gdx.graphics.getHeight(), 0);
screenCamera.unproject(vec1);
screenQuad.setVertices(new float[] {vec0.x, vec0.y, 0, 1, 1, 1, 1, 0, 1, vec1.x, vec0.y, 0, 1, 1, 1, 1, 1, 1, vec1.x,
vec1.y, 0, 1, 1, 1, 1, 1, 0, vec0.x, vec1.y, 0, 1, 1, 1, 1, 0, 0});
screenQuad.setIndices(new short[] {0, 1, 2, 2, 3, 0});
}
}