Bug 198039 – [Mac] gl.clear() does not clear, when rendering into a texture on Radeon Pro 560

• Status: NEW
• Component: WebGL

[Ivan Kuckir]

Hi,

I am the creator of Photopea.com and a user reported a bug in Safari, Radeon Pro 560 4 GB, described here: https://github.com/photopea/photopea/issues/1365

I don't have a Mac OS device to be able to test it, or prepare a reduced case. But my guess is, that this code 

gl.colorMask(true,true,true,true);
gl.clearColor(0,0,0,0);
gl.clear(gl.COLOR_BUFFER_BIT);
gl.colorMask(true, true, true, true);

doesn't clear the texture, when rendering into a texture. Could you try it out?

Or go to www.Photopea.com and open any image (JPG, PNG ...). Choose a Rectangle Select tool (in the toolbar on the left) and draw a rectangle. Now, press Ctrl+D (Deselect), the rectangle should disappear. Check what WebGL commands are done after pressing Ctrl+D - that is where the bug occurs.

[Radar WebKit Bug Importer]

<rdar://problem/50967741>