Developed for Zense HacKnight 2K19

Authors

• Satvik Ramaprasad
• Shubhayu Das
• Rohit Katlaa
• Prajwal Agarwal
• Jishnu Kumar

Instructions for users

• You need not understand the code here to be able to use it.
• Understanding the API below should be enough
• See Examples to get started.

API Documentation

Helpful Canvas Variables

• canvas.height: Height
• canvas.width: Width
• canvas.mouseX: Current Position of mouse x coordinate
• canvas.mouseY: Current Position of mouse y coordinate
• canvas.mouseDown: Boolean to check if mouse is pressed down
• canvas.mouseDownX: Last Position of mouse press x coordinate
• canvas.mouseDownY: Last Position of mouse press y coordinate
• canvas.drawMode: Fill in a shape or just draw the border

Helpful Canvas Functions

• canvas.setDrawMode(mode): Set the drawMode variable to "stroke" or "fill"
• canvas.setColor(color): Set the color of the shape(s) to the given color. Default color is black(#000000)
  • Value can be any one of these types:
    1. "red"
    2. "#F54680"
    3. "rgb(100,100,100)"
    4. "rgba(100,100,101,0.3)"
• canvas.setLineThickness(width): Set the thickness of the lines while in "fill draw mode". Default value is 1.
• canvas.draw(): Draws the various shapes according to the drawing mode.
• canvas.drawLine(x1, y1, x2, y2): Draws line from (x1, y1) to (x2, y2)
• canvas.drawCircle(x, y, r): Draws circle with center (x, y) and radius r
• canvas.drawRectangle(x, y, width, height): Draws rectangle with top left corner as (x, y) and of dimensions width * height
• canvas.drawEllipse(x, y, a, b, angle, startAngle, endAngle): Draws an Ellipse with center(x,y) with major axis = a, minor axis = b at an angle theta given the startAngle And Endangle
• canvas.clear(): Clears the canvas
• canvas.isKeyDown(key): Checks if keyboard key is pressed. Example KeyA for A.
• canvas.drawText(x, y, message, fontSize = 30): Draws at (x, y)
• canvas.activateDoubleBuffer(): Call in setup to use double buffering in your program.
• canvas.update(): Updates the screen with changes made on canvas(use only with double buffering)
• canvas.drawImg(path,x,y,width,height): Draws an image at (x,y). "path" argument is used to mention the path of the image (width and height of the image are optional)

Optionally Override the following functions

• canvas.mouseDownCallback(): Called when mouse is pressed
• canvas.mouseUpCallback(): Called when mouse is released
• canvas.mouseMoveCallback(): Called when mouse is moved
• canvas.keyDownCallback(): Called when key is pressed
• canvas.keyUpCallback(): Called when mouse is released
• canvas.mainFunction(): Called after every timeStep

Note:(Regarding double buffering) Double buffering is entirely optional, you may not need it in your program. It is only required if you face flickering issues.