mwisniewski0/globus-map-projector

WebGL-based program for converting between different projections of the sphere

globus-map-projector

WebGL-based program for converting between different projections of the sphere

Hosted at: https://www.winski.net/?page_id=12

globus-map-projector's Issues

Use double precision in the glsl shaders

Impossible to save large canvases on all browsers

• Saving large canvases is impossible on all major browsers. It is a browser-side issue
• The possible solution includes dividing the canvas into smaller savable canvas. Then the user can save the result and stitch it back together.
• To ease the process, the stitched up image could be uploaded to a storage service like gdrive
• Firefox claims to support unlimited length of data urls. This might enable saving the stitched canvas from an tag with src=.
• Splitting the image into smaller canvases would also fix issue #2

Allow using .tiff images

Reorganize source using require.js

Perform rendering in a web worker

Issue #3 requires rendering to multiple canvases. This gets fairly slow for bigger canvases, and it would cause the UI to freeze for minutes. Processing the rendering in a web worker will allow to handle UI events as the rendering happens in the background. Moreover, a progress bar will be possible to display too.

Browsers limit effective render size

• All browsers reduce the size of the WebGL draw buffer for large canvases (usually over 4096px in width or height).
• Until the issue is solved, the problem is least visible on Firefox, which accepts canvases up to 16000px in width and height (tested on yoga 720 with GTX 1050M).
• The browser will stretch the render to the original size of the canvas causing jagged or pixelated images.

Allow for staggered gores in the sinusoidal projection

Example: