pixel-editor/js/_checkerboard.js
npalomba f7100ff9f7 Added comments, removed unused variables.
Signed-off-by: npalomba <nicola.palomba@studenti.galileilivorno.gov.it>
2019-04-01 21:37:53 +02:00

59 lines
1.9 KiB
JavaScript

// This script contains all the functions used to manage the checkboard
// Setting current colour (each square has a different colour
var currentColor = firstCheckerBoardColor;
// Saving number of squares filled until now
var nSquaresFilled = 0;
function fillCheckerboard() {
// Getting checkerboard context
var context = checkerBoard.context;
// Cycling through the canvas (using it as a matrix)
for (var i=0; i<canvasSize[0] / checkerBoardSquareSize; i++) {
nSquaresFilled = 0;
for (var j=0; j<canvasSize[1] / checkerBoardSquareSize; j++) {
var rectX;
var rectY;
// Managing the not perfect squares (the ones at the sides if the canvas' sizes are not powers of checkerBoardSquareSize
if (i * checkerBoardSquareSize < canvasSize[0]) {
rectX = i * checkerBoardSquareSize;
}
else {
rectX = canvasSize[0];
}
if (j * checkerBoardSquareSize < canvasSize[1]) {
rectY = j * checkerBoardSquareSize;
}
else {
rectY = canvasSize[1];
}
// Selecting the colour
context.fillStyle = currentColor;
context.fillRect(rectX, rectY, checkerBoardSquareSize, checkerBoardSquareSize);
// Changing colour
changeCheckerboardColor();
nSquaresFilled++;
}
// If the number of filled squares was even, I change colour for the next column
if ((nSquaresFilled % 2) == 0) {
changeCheckerboardColor();
}
}
}
// Simply switches the checkerboard colour
function changeCheckerboardColor(isVertical) {
if (currentColor == firstCheckerBoardColor) {
currentColor = secondCheckerBoardColor;
} else if (currentColor == secondCheckerBoardColor) {
currentColor = firstCheckerBoardColor;
}
}