-- Physics debug drawing:  physicsSetDebug draws the bodies, joints, contacts and velocities as
-- lines over the scene (static shapes too, with DEBUG_STATIC); lineDraw draws the script's own
-- ray cast for the frame, and navDraw the navigation mesh baked from the ground and the wall.
local font   = fontLoad("Singe/FreeSansBold.ttf", 28)
local frames = 0

fontSelect(font)
sceneEnable(true)
sceneSetBackground(40, 45, 60)
sceneSetAmbient(90, 90, 100)

local grey = materialNew()
materialSetColor(grey, 120, 120, 125)
local wood = materialNew()
materialSetColor(wood, 150, 100, 55)

local ground = nodeNew()
nodeSetMesh(ground, meshBox(24, 1, 24), grey)
nodeSetPosition(ground, 0, -0.5, 0)
bodyNew(ground, BODY_STATIC, SHAPE_BOX, 24, 1, 24)

local wall = nodeNew()
nodeSetMesh(wall, meshBox(1, 2, 8), grey)
nodeSetPosition(wall, 2, 1, 0)
bodyNew(wall, BODY_STATIC, SHAPE_BOX, 1, 2, 8)

-- Crates and a ball dropped in a heap.
for i = 1, 8 do
	local crate = nodeNew()
	nodeSetMesh(crate, meshBox(1, 1, 1), wood)
	nodeSetPosition(crate, -6 + i * 1.2, 3 + i * 1.3, -5 + (i % 3) * 2)
	nodeSetRotation(crate, i * 17, i * 31, 0)
	bodyNew(crate, BODY_DYNAMIC, SHAPE_BOX, 1, 1, 1)
end
local ball = nodeNew()
nodeSetMesh(ball, meshSphere(0.6), wood)
nodeSetPosition(ball, -4, 8, 4)
bodyNew(ball, BODY_DYNAMIC, SHAPE_SPHERE, 0.6)

-- A bar hinged to a fixed block, swinging.
local post = nodeNew()
nodeSetMesh(post, meshBox(0.4, 0.4, 0.4), grey)
nodeSetPosition(post, 6, 6, -3)
bodyNew(post, BODY_STATIC, SHAPE_BOX, 0.4, 0.4, 0.4)
local bar = nodeNew()
nodeSetMesh(bar, meshBox(0.3, 3, 0.3), wood)
nodeSetPosition(bar, 7.7, 6, -3)
nodeSetRotation(bar, 0, 0, 90)
bodyNew(bar, BODY_DYNAMIC, SHAPE_BOX, 0.3, 3, 0.3)
jointHinge(post, bar, 6, 6, -3, 0, 0, 1)

-- A player capsule walking across.
local player = nodeNew()
nodeSetMesh(player, meshCylinder(0.4, 1.8), wood)
nodeSetPosition(player, -9, 0.9, 6)
playerNew(player, 0.4, 1.8)

-- Everything walkable, for navDraw.
local nav = navNew(0.4, 1.8, 45, 0.4)
navAddNode(nav, ground)
navAddNode(nav, wall)
navBuild(nav)

physicsSetDebug(DEBUG_ALL + DEBUG_STATIC)

local sun = lightNew(LIGHT_DIRECTIONAL)
nodeSetPosition(sun, 20, 30, 10)
nodeLookAt(sun, 0, 0, 0)
lightSetIntensity(sun, 2)
lightSetShadow(sun, true)

local camera = nodeNew()
cameraSet(camera)
cameraSetPerspective(55, 0.1, 200)

local stops = {
	{ 0, 9, 18,      0, 1, 0 },        -- The whole heap
	{ -8, 4, 8,      -3, 1, 0 },       -- Crates and the ball, close
	{ 12, 6, 4,      6, 5, -3 },       -- The hinged bar
	{ 0, 20, 1,      0, 0, 0 },        -- From above:  the nav mesh around the wall
}

function onOverlayUpdate()
	local stop = stops[math.min(#stops, math.floor(frames / 45) + 1)]
	frames = frames + 1
	nodeSetPosition(camera, stop[1], stop[2], stop[3])
	nodeLookAt(camera, stop[4], stop[5], stop[6])
	playerMove(player, 1.5, -0.6)
	-- A ray from above the heap straight down, drawn to whatever it hits.
	local hit, hx, hy, hz = physicsRaycast(-3, 12, -1, 0, -1, 0, 30)
	if hit then
		lineDraw(-3, 12, -1, hx, hy, hz, 255, 255, 0)
	end
	navDraw(nav)
	local x, y, z = nodeGetWorldPosition(player)
	overlayClear()
	fontPrint(20, 20, string.format("Physics debug, frame %d  player at %.1f %.1f %.1f  ray hit %s", frames, x, y, z, hit and "yes" or "no"))
	if frames == 40 or frames == 85 or frames == 130 or frames == 175 then
		singeScreenshot()
		debugPrint(string.format("frame %d player at %.2f %.2f %.2f hit %s", frames, x, y, z, tostring(hit)))
	end
	if frames == 180 then
		singeQuit()
	end
end