Tag Archives: recipe 9

Offscreen drawing

Making my way through the Offscreen drawing recipe from the Processing 2 Creative programming cookbook source code on GitHub. In this recipe I learned how to:

  • declare a PGraphics object and then initialise it with the createGraphics function inside the setup function.
  • use the createGraphics function to create a new transparent image to be drawn on and the beginDraw and endDraw functions to start and stop drawing on the image. For this Sketch, strokes and lines are drawn on the PGraphics object. To do this, they needed to be prefixed with a variable (pg).

ch02_r09_002
The display window is cleared every time the mouse is pressed. The if test inside the mousePressed function specifies there’s a 50 percent chance the new background will be black or white.
ch02_r09_001

ch02_r09_005

Mouse interaction

Making my way through the Mouse interaction recipe from the Processing 2 Creative programming cookbook source code on GitHub. In this recipe I learned about the mouseClicked, mouseDragged, mouseMoved, mousePressed and mouseReleased functions. I also learned about the mouseX, mouseY, pmouseX, pmouseY, mousePressed and mouseButton variable. The mouseButton variable allows you to determine if the left, right or middle mouse button has been clicked. This recipe is also the first time an if test has been used. They’re cool. I know I’ll be using them heavily to determine the display or actions in future sketches.

Screen Shot 2014-01-25 at 10.58.01 PM