Here is my implementation of drawRoundedRect using the BASIC version of Bresenham's algorithm as described in Wikipedia.

drawRoundedRect

Please note: the Bresenham algorithm makes a few assumptions (e.g., x1 <= x2) which have been taken care of in the following code as well:

x1 <= x2

let ScreenWidth = g.getWidth(), CenterX = ScreenWidth/2; let ScreenHeight = g.getHeight(), CenterY = ScreenHeight/2; g.setBgColor('#000000'); g.clear(false); g.drawRoundedRect = function drawRoundedRect (x1,y1, x2,y2, r) { let x,y; if (x1 > x2) { x = x1; x1 = x2; x2 = x; } if (y1 > y2) { y = y1; y1 = y2; y2 = y; } r = Math.min(r || 0, (x2-x1)/2, (y2-y1)/2); let cx1 = x1+r, cx2 = x2-r; let cy1 = y1+r, cy2 = y2-r; this.drawLine(cx1,y1, cx2,y1); this.drawLine(cx1,y2, cx2,y2); this.drawLine(x1,cy1, x1,cy2); this.drawLine(x2,cy1, x2,cy2); x = r; y = 0; let dx,dy, Error = 0; while (y <= x) { dy = 1 + 2*y; y++; Error -= dy; if (Error < 0) { dx = 1 - 2*x; x--; Error -= dx; } this.setPixel(cx1 - x, cy1 - y); this.setPixel(cx1 - y, cy1 - x); this.setPixel(cx2 + x, cy1 - y); this.setPixel(cx2 + y, cy1 - x); this.setPixel(cx2 + x, cy2 + y); this.setPixel(cx2 + y, cy2 + x); this.setPixel(cx1 - x, cy2 + y); this.setPixel(cx1 - y, cy2 + x); } }; g.setColor('#FFFFFF'); g.drawRoundedRect(120,50, 50,120, 100);

It would be interesting to see how that performs compared to the C variant.

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@Andreas_Rozek started

Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.

Andreas_RozekHere is my implementation of

`drawRoundedRect`

using the BASIC version of Bresenham's algorithm as described in Wikipedia.Please note: the Bresenham algorithm makes a few assumptions (e.g.,

`x1 <= x2`

) which have been taken care of in the following code as well:It would be interesting to see how that performs compared to the C variant.

1 Attachment