src/vs/editor/browser/controller/mouseTarget.ts/BareHitTestRequest/constructor
class BareHitTestRequest:	constructor(ctx: HitTestContext, editorPos: EditorPagePosition, pos: PageCoordinates, relativePos: CoordinatesRelativeToEditor) {
		this.editorPos = editorPos;
		this.pos = pos;
		this.relativePos = relativePos;

		this.mouseVerticalOffset = Math.max(0, ctx.getCurrentScrollTop() + this.relativePos.y);
		this.mouseContentHorizontalOffset = ctx.getCurrentScrollLeft() + this.relativePos.x - ctx.layoutInfo.contentLeft;
		this.isInMarginArea = (this.relativePos.x < ctx.layoutInfo.contentLeft && this.relativePos.x >= ctx.layoutInfo.glyphMarginLeft);
		this.isInContentArea = !this.isInMarginArea;
		this.mouseColumn = Math.max(0, MouseTargetFactory._getMouseColumn(this.mouseContentHorizontalOffset, ctx.typicalHalfwidthCharacterWidth));
	}