Camera non-default viewport size ignores camera clear color

[MarlonLam]

Description

When changing the camera viewport from default (0, 0, 1, 1) to non-default values e.g. (0.01, 0, 1, 1), the camera's clear color is ignored.

Test URL

Test project: https://playcanvas.com/editor/scene/1980662

Screenshots

(0, 0, 1, 1):

(0.01, 0, 1, 1):

Platform

Tested in Edge

Steps to Reproduce

1. Set camera viewport size to something other than (0, 0, 1, 1)
2. Launch

Additional Notes

From my own digging around, I found a property assignment for "clearColor":

engine/src/scene/renderer/render-pass-forward.js

Lines 273 to 280 in 4ab0ace

 if (!firstRenderAction || !camera.camera.fullSizeClearRect) { 
     options.clearColor = renderAction.clearColor; 
     options.clearDepth = renderAction.clearDepth; 
     options.clearStencil = renderAction.clearStencil; 
 } 
  
 renderer.renderForwardLayer(camera.camera, renderAction.renderTarget, layer, transparent, 
                             shaderPass, renderAction.viewBindGroups, options); 

But in "renderForwardLayer" function, the property read is "clearColors":

engine/src/scene/renderer/forward-renderer.js

Lines 696 to 701 in 4ab0ace

 const clearColor = options.clearColors ?? false; 
 const clearDepth = options.clearDepth ?? false; 
 const clearStencil = options.clearStencil ?? false; 
 if (clearColor || clearDepth || clearStencil) { 
     this.clear(camera, clearColor, clearDepth, clearStencil); 
 } 

[Martin Valigursky]

Thanks for this, easy to fix if you just point it out to us!