O'Reilly logo

Mastering openFrameworks: Creative Coding Demystified by Denis Perevalov

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Using vertex shader in our project

In the testApp.h file, in the testApp class declaration, add the shader object declaration as follows:

ofShader shader;  //Shader

At the end of the setup() function declaration, add the following line for loading shaders:

shader.load( "shaderVert.c", "shaderFrag.c" );

Change the empty update() function with the following code:

float time0 = 0;
float phase = 0;
float distortAmount = 0;

void testApp::update(){
  //Compute dt
  float time = ofGetElapsedTimef();
  float dt = ofClamp( time - time0, 0, 0.1 );
  time0 = time;

  float speed = ofMap( mouseY, 0, ofGetHeight(), 0, 5 );
  phase += speed * dt;
  distortAmount = ofMap( mouseX, 0, ofGetWidth(), 0, 1.0 );
}

This function computes time step dt as a time difference between the current ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required