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Re: [ft-devel] [GSoC] [Doubt] Bitmap rendering

From: Arvinder Bhathal
Subject: Re: [ft-devel] [GSoC] [Doubt] Bitmap rendering
Date: Fri, 23 Jun 2017 13:24:55 -0400

> I wanted to know if anyone knew how to display the pixel grid
> (like the one in ftgrid) on webpage. (Arvinder ?)

If the goal is just to have a grid of some size with pixel-level
control, then a canvas of the appropriate size would do.
  // create a blank canvas
  <canvas id="canvas" width="100" height ="100"></canvas>
  In JS:
  var canvas = document.getElementById('canvas');
  var ctx = canvas.getContext('2d');
  // get a pixel from the canvas
  var pixel= ctx.getImageData(x-coord, y-coord, 1, 1);
  // pixelData is an array of unsigned 8-bit integers representing
pixel data in RGBA order. If 'pixel' was more than a single pixel, the
data would be ordered row by row
  var pixelData =;
  // make the pixel black
  pixelData[0] = 0;
  pixelData[1] = 0;
  pixelData[2] = 0;
  // write the pixel back to the canvas
  ctx.putImageData(pixel, x-coord, y-coord);

Is this any help? I think I may have missed the goal of what you
wanted from the grid since the resulting image from all the above
could just be done in C.

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