TouchShield Description

The Liquidware TouchShield and TouchSlide are add on shields for the Arduino family of processors. They are both fully compatible with the Arduino development environment. A full graphics library is provided to draw lines, colors, shapes and images on the screen. The library is compatible with the Processing graphics language and an Mac QuickDraw style command set is in the works

Software API Reference

Processing is the language of the TouchShield as programmed through the Arduino Environment Windows and Mac. See the software download section to grab the IDE.


Gadget

Serial
beginCanvas() – Accept drawing functions from the Arduino
delay() – Delay for a passed millisecond amount of time
random() – Generates a random number (long number)


Input

Touchscreen
gettouch() – Check the touch screen for a press at a pixel location
mouseX – Stored variable when “gettouch()” is called (X location of press)
mouseY – Stored variable when “gettouch()” is called (Y location of press)
touch_get_cursor() – old style single press
touch_calibrate() – Reset the previous calibration and prompt a recalibration


Shape

2D Primitives
ellipse() – Draws an ellipse of a user specified size and location
line() – Draw a line from point to point
point() – Draw a single pixel
rect() – Draw a rectangle with a specified beginning point, width and height
triangle() – Draw a triangle with three specified points
quad() – Draw a polygon with 4 specified lines from 4 specified points
size() – for clipping shapes
new for version 1.1.1
bezeir() draw a bezeir curve
arc() draw a partial circle/ellipse from start angle to end angle


Color

Setting
background() – Color the whole screen any of 16,777,216 different colors
fill() – Sets the color used to fill the inside shapes
nofill() – Will allow a shape to be drawn with nothing filled in the inside
stroke() – Sets the color of shape outlines or text
noStroke() – Allows a shape to be drawn without an outline drawn
strokeWeight() – changes the outline thickness of an ellipse or rectangle


Image Uploading

open(FlashTransfer) – The TouchShield will wait in this function till an image is uploaded to the device

loadImage(”.bmp”) – refers to an image store on the flash chip
image(loadImage(”.bmp”),0,0) – Paints the image at point 0,0
PImage – Define an image as a variable
Blog Demo


Typography

text() – for printing char[], int, long, and float types to the screen


Simple Example

MikeExample – getting started with my stealth and slide



Hardware Description

Pins – Explains what pins the TouchShield uses on the Arduino

TouchShield Slide:

Low level pin register descriptions


Low Level Functions

HersheyDrawCString() Draw vector font based on Hershey font data. Scaling and rotating supported, pen size not.

If you have questions or need any additions to these routines, please email msproul@jove.rutgers.edu