Fix p5.Geometry absorbing the ambient fill color

src/webgl/p5.RendererGL.js

@@ -46,6 +46,7 @@ import filterInvertFrag from "./shaders/filters/invert.frag";
 import filterThresholdFrag from "./shaders/filters/threshold.frag";
 import filterShaderVert from "./shaders/filters/default.vert";
 import { PrimitiveToVerticesConverter } from "../shape/custom_shapes";
+import { Color } from "../color/p5.Color";
 
 const STROKE_CAP_ENUM = {};
 const STROKE_JOIN_ENUM = {};
@@ -438,8 +439,8 @@ class RendererGL extends Renderer {
       );
     }
     this.geometryBuilder = new GeometryBuilder(this);
-    this.geometryBuilder.prevFillColor = [...this.states.curFillColor];
-    this.states.curFillColor = [-1, -1, -1, -1];
+    this.geometryBuilder.prevFillColor = this.states.fillColor;
+    this.fill(new Color([-1, -1, -1, -1]));
   }
 
   /**
@@ -458,7 +459,7 @@ class RendererGL extends Renderer {
       );
     }
     const geometry = this.geometryBuilder.finish();
-    this.states.curFillColor = this.geometryBuilder.prevFillColor;
+    this.fill(this.geometryBuilder.prevFillColor);
     this.geometryBuilder = undefined;
     return geometry;
   }

test/unit/visual/cases/webgl.js

@@ -581,5 +581,29 @@ visualSuite('WebGL', function() {
       p5.model(geom);
       screenshot();
     });
+
+    visualTest('only fills set in buildGeometry are kept', (p5, screenshot) => {
+      p5.createCanvas(50, 50, p5.WEBGL);
+
+      const geom = p5.buildGeometry(() => {
+        p5.push();
+        p5.translate(-p5.width*0.2, 0);
+        p5.scale(0.15);
+        p5.sphere();
+        p5.pop();
+
+        p5.push();
+        p5.fill('red');
+        p5.translate(p5.width*0.2, 0);
+        p5.scale(0.15);
+        p5.sphere();
+        p5.pop();
+      });
+
+      p5.fill('blue');
+      p5.noStroke();
+      p5.model(geom);
+      screenshot();
+    });
   });
 });

test/unit/visual/screenshots/WebGL/buildGeometry()/only fills set in buildGeometry are kept/metadata.json

@@ -0,0 +1,3 @@
+{
+  "numScreenshots": 1
+}