Slit-Scan from Form+Code in Art, Design, and Architecture; Cinder version fork

SlitScanCamCinder.cpp

/**
 * Forked by Forrest Oliphant, http://sembiki.com/ 
 * Simplified from:
 *
 * Transform: Slit-Scan from Form+Code in Art, Design, and Architecture
 * implemented in C++ by Patrick Tierney <http://ptierney.com>
 *
 * Requires Cinder 0.8.2 available at http://libcinder.org
 *
 * Project files are located at https://github.com/hlp/form-and-code
 *
 * For more information about Form+Code visit http://formandcode.com
 */

#include "cinder/app/AppBasic.h"
#include "cinder/Surface.h"
#include "cinder/Capture.h"
#include "cinder/gl/gl.h"
#include "cinder/gl/Texture.h"

using namespace ci;

class Transform_SlitScan : public ci::app::AppBasic {
public:
  void prepareSettings(Settings* settings);
  void setup();
  void update();
  void draw();
  
private:
  Capture capture;
  Surface inSurface;
  Surface outSurface;
  
  int video_width;
  int video_height;
  int video_slice_x;
  int window_width;
  int window_height;
  int draw_position_x;
  bool newFrame;
  
};

void Transform_SlitScan::prepareSettings(Settings* settings) {
  video_width = 320;
  video_height = 240;
  video_slice_x = video_width / 2;
  window_width = 1000;
  window_height = video_height;
  draw_position_x = 0;
  newFrame = false;
  
  outSurface = Surface(window_width, window_height, ci::SurfaceChannelOrder::RGB);
  
  settings->setWindowSize(window_width, window_height);
}

void Transform_SlitScan::setup() {
  try {
    capture = ci::Capture(video_width, video_height);
    capture.start();
  } catch (...) {
    // if we threw in the start close the program 
    ci::app::console() << "Unable to open webcam." << std::endl;
    exit(1);
  }
  
  if (capture.getWidth() != video_width || capture.getHeight() != video_height) {
    ci::app::console() << "Unable to open webcam at desired size." << std::endl;
    exit(1);
  }  
}

void Transform_SlitScan::update() {
  newFrame = false;
  
  if (!capture || !capture.checkNewFrame()) 
    return;
  
  newFrame = true;
  
  inSurface = capture.getSurface();
  
  outSurface.copyFrom(inSurface, Area( video_slice_x, 0, video_slice_x+1, video_height ), Vec2i( draw_position_x - video_slice_x, 0 ) );
  
}

void Transform_SlitScan::draw() {
  if (!newFrame)
    return;
  
  draw_position_x++;
  
  if (draw_position_x >= window_width)
    draw_position_x = 0;
  
  if( outSurface )
    gl::draw( gl::Texture( outSurface ) ); 
  
}

CINDER_APP_BASIC(Transform_SlitScan, ci::app::RendererGl)