-- Overlay layers round guiDraw:  what a script draws before a guiDraw is under the document and
-- what it draws after is over it, so a gun's sight or an editor's pointer is never hidden by a
-- HUD.  Forge's own chrome, an opaque panel down the left, is the document:  a red box is drawn
-- before it and a yellow cross after it, both across the panel's edge, and the shot shows the box
-- cut off by the panel and the cross whole over it.  Then a second copy of the panel drawn small
-- after the cross, with a blue box drawn after that, three layers deep.
local font = fontLoad("Singe/FreeSansBold.ttf", 16)
local gui  = guiNew(720, 480)
local doc  = guiLoad(gui, "Forge/Forge.rml")
local gui2 = guiNew(720, 480)
local doc2 = guiLoad(gui2, "Forge/Forge.rml")
local frames = 0

fontSelect(font)
fontQuality(FONT_QUALITY_BLENDED)
overlaySetResolution(720, 480)


function onOverlayUpdate()
	frames = frames + 1
	colorBackground(20, 20, 30, 255)
	overlayClear()
	-- Under the panel:  a red box across its right edge (the panel is 190 wide, and its grip
	-- and title are the opaque part of an empty one, across the top).
	colorForeground(230, 60, 60, 255)
	for y = 40, 80 do
		overlayLine(100, y, 300, y)
	end
	guiDraw(gui)
	-- Over it:  a yellow cross on the panel's edge, and a line of text.
	colorForeground(255, 220, 60, 255)
	overlayLine(150, 60, 230, 60)
	overlayLine(190, 20, 190, 100)
	fontPrint(220, 300, "drawn after guiDraw:  over the panel")
	-- A second panel, drawn small over the cross's layer, and a blue box over its grip.
	guiDraw(gui2, 400, 150, 240, 160)
	colorForeground(80, 120, 255, 255)
	for y = 150, 170 do
		overlayLine(380, y, 480, y)
	end
	if frames == 10 then
		singeScreenshot("layers")
		debugPrint("LAYERS two panels queued, each with what follows it on a layer of its own;  see the shot")
		debugPrint("LAYERS RESULT done")
	end
	if frames > 14 then
		singeQuit()
	end

	return OVERLAY_UPDATED
end