I use ShapeRenderer from Libgdx to draw a rectangle and draw waves using shaders. In the game I move objects to create the effect of the paralax, using the projection matrix translate.
ShapeRenderer translate matrix - the drawn rectangle moves, why the drawn waves do not move through shaders in the rectangle?
in the fragment shader to consider the projection matrix?
Grateful for any help

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package com.mygdx.game; import com.badlogic.gdx.ApplicationAdapter; import com.badlogic.gdx.Gdx; import com.badlogic.gdx.InputProcessor; import com.badlogic.gdx.graphics.GL20; import com.badlogic.gdx.graphics.glutils.ShaderProgram; import com.badlogic.gdx.graphics.glutils.ShapeRenderer; import com.badlogic.gdx.graphics.glutils.ShapeRenderer.ShapeType; import com.badlogic.gdx.math.Matrix4; import com.badlogic.gdx.math.Vector2; public class MyGdxGame extends ApplicationAdapter implements InputProcessor { private float mX; private float mY; private ShaderProgram mGradientShader; private Matrix4 mProjection = new Matrix4(); private ShapeRenderer mShapeRender; public MyGdxGame() { } private float iGlobalTime = 0.0f; private Vector2 mScreenResolution; @Override public void create () { final float screenWidth = Gdx.graphics.getWidth(); final float screenHeight = Gdx.graphics.getHeight(); mScreenResolution = new Vector2( screenWidth, screenHeight ); mX = screenWidth / 2.0f; mY = screenHeight / 2.0f; String vertexShader = Gdx.files.local( "vertex.glsl" ).readString(); String fragmentShader = Gdx.files.local( "fragment.glsl" ).readString(); ShaderProgram.pedantic = false; mGradientShader = new ShaderProgram( vertexShader, fragmentShader ); String s = ""; if( false == mGradientShader.isCompiled() ) { s = mGradientShader.getLog(); Gdx.app.log( "Asteroid", s ); } mProjection.setToOrtho2D( 0, 0, Gdx.graphics.getWidth(), Gdx.graphics.getHeight() ); mShapeRender = new ShapeRenderer( 19, mGradientShader ); Gdx.input.setInputProcessor( this ); } @Override public void render () { Gdx.gl.glClearColor( 1, 0, 0, 1 ); Gdx.gl.glClear( GL20.GL_COLOR_BUFFER_BIT ); Gdx.gl.glBlendFunc( GL20.GL_SRC_ALPHA, GL20.GL_ONE_MINUS_SRC_ALPHA ); Gdx.gl.glEnable( GL20.GL_BLEND ); mProjection.translate( 1.0f, 0.0f, 0.0f ); final int width = 400; final int height = 400; mGradientShader.begin(); mGradientShader.setUniformf( "u_parentAlpha", 1.0f ); mGradientShader.setUniformf( "iGlobalTime", iGlobalTime ); mGradientShader.setUniformf( "iResolution", mScreenResolution ); mGradientShader.setUniformf( "u_size", width, height ); mGradientShader.setUniformMatrix("u_projTrans", mProjection ); mGradientShader.setUniformf("u_center", mX, mY ); mGradientShader.end(); mShapeRender.begin( ShapeType.Filled ); mShapeRender.rect( mX - width / 2.0f, mY - height / 2.0f, width - 100, height ); mShapeRender.end(); iGlobalTime += Gdx.graphics.getDeltaTime(); } @Override public boolean keyDown(int keycode) { // TODO Auto-generated method stub return false; } @Override public boolean keyUp(int keycode) { // TODO Auto-generated method stub return false; } @Override public boolean keyTyped(char character) { // TODO Auto-generated method stub return false; } @Override public boolean touchDown(int screenX, int screenY, int pointer, int button) { mX = screenX; mY = Gdx.graphics.getHeight() - screenY; return false; } @Override public boolean touchUp(int screenX, int screenY, int pointer, int button) { // TODO Auto-generated method stub return false; } @Override public boolean touchDragged(int screenX, int screenY, int pointer) { mX = screenX; mY = Gdx.graphics.getHeight() - screenY; return false; } @Override public boolean mouseMoved(int screenX, int screenY) { // TODO Auto-generated method stub return false; } @Override public boolean scrolled(int amount) { // TODO Auto-generated method stub return false; } } //###########################Vertex shader attribute vec4 a_position; attribute vec4 a_color; attribute vec2 a_texCoord0; uniform mat4 u_projTrans; varying vec4 v_color; varying vec2 v_texCoords; void main() { v_color = a_color; v_color.a = v_color.a * (255.0/254.0); v_texCoords = a_texCoord0; gl_Position = u_projTrans * a_position ; } //###########################Fragment shader #ifdef GL_ES #define LOWP lowp precision mediump float; #else #define LOWP #endif varying LOWP vec4 v_color; varying vec2 v_texCoords; uniform sampler2D u_texture; uniform float u_outterRadius; uniform vec2 u_center; uniform float u_parentAlpha; uniform float iGlobalTime; uniform vec2 iResolution; uniform vec2 u_size; float speed = 0.03; float invAr = iResolution.y / iResolution.x; void main() { //determine origin vec2 position = ( gl_FragCoord.xy - u_center ) / u_size.xy; //determine the vector length of the center position float len = length( abs( position ) ); float softness = 0.01; float waves_count = 2.0; float wave_spliter = 0.05; vec2 center = u_center / iResolution; vec2 uv = gl_FragCoord.xy / iResolution.xy; // vec3 col = vec4( uv, 0.5 + 0.5 * sin( iGlobalTime ), 0.0 ).xyz; // vec3 col = vec4( uv, 0.5, 0.0 ).xyz; vec3 col = vec3( 0.5, 0.5, 0.5 ); vec3 texcol; float x = ( center.x - uv.x ); float y = ( center.y - uv.y ) * invAr; float r = ( - 1.0 ) * sqrt( x * x + y * y ); //uncoment this line to symmetric ripples //float r = ( - 1.0 ) * ( x * x + y * y); float z = 1.0 + 0.5 * sin( ( r - iGlobalTime * speed ) / 0.003 ); texcol.x = z; texcol.y = z; texcol.z = z; gl_FragColor = vec4( col * texcol, z * ( 1.0 - 2.0 * len ) ); }
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  • thank you. I corrected - vadimostanin
  • I think the question can be closed. I found a solution, details in the question description. Thanks to all. - vadimostanin
  • one
    @vadimostanin but you can pull the solution out of the question in response and check it with a daw. And, potentially, to get a turnip for him, if he helps someone else. It is customary here to close more holivars and offtopic, this question does not apply to them. - D-side
  • Thanks for the advice. I didn’t do it right away because, in the comments, it’s impossible to do "Indent four spaces to create an isolated <pre> <code> block." . And I want to start Enter'om new line, and the site "Comment" button handles. Bug - vadimostanin

1 answer 1

thanks for the help
I found a solution:

 private Vector3 mMatrixGetTranslation = new Vector3();

in render ()

 mProjection.getTranslation( mMatrixGetTranslation ); float tranX = ( Gdx.graphics.getWidth() + mMatrixGetTranslation.x * Gdx.graphics.getWidth() ) / 2.0f; float tranY = ( Gdx.graphics.getHeight() + mMatrixGetTranslation.y * Gdx.graphics.getHeight() ) / 2.0f;

and finally

 mGradientShader.setUniformf("u_center", mX + tranX, mY + tranY );