Very low camera fov and shadows

[Rick]

When trying to get a more isometric style I put the camera's fov to about 25 or so. I rotate the camera 45 degrees on x & y axis and move it back. Because the fov needs to be around 25 to get the isometric look, I have to zoom the camera way back (about -40). I think however this is out of shadow drawing range so there are no shadows which kills the effect.

 

How can I make shadows stay no matter what or increase the view range of them in the editor?

[Josh]

This is a tricky situation because cascaded shadow maps are sort of at odds with orthographic rendering. The whole idea of CSM is greater resolution near the camera, but without a perspective projection that makes no sense.

 

There is a DirectionalLight class member you can set in the engine that controls the shadow map stage ranges:

float shadowstagerange[4]

 

[macklebee]

You may have to adjust the stages' linear offset as well if you modify the stage's range. See here for a script that allows for modifying the linear offset in game to help remove artifacts: http://www.leadwerks.com/werkspace/topic/14985-changing-shadow-resolution/#entry101390

[Rick]

@Josh So is that exposed to Lua by chance? Was hoping to have this play in the game launcher app.

[macklebee]

Its exposed to lua - see the script i posted in the link above. Whether or not its exposed to the game launcher app depends on what build the launcher is made from and if it was exposed in that version.

[Rick]

I see. So what's the idea here? I'm not sure how this shadow stuff works. I set:

 

self.entity.shadowstagerange[3] = 1000

 

and still can't see the shadow. What are these ranges in? meters? Why 4 ranges? If you had to guess what values would I set each to in order to see the shadows because I'm randomly setting stuff and can't see any shadows?

[macklebee]

You have to look at each stage with ranges in meters. Try this script attached to your directional light to see the affect of changing the stages' ranges:

function Script:Start()
	self.value = 5
end

function Script:UpdateWorld()
	local window = Window:GetCurrent()
	if window:KeyHit(Key.Up)==true then
		self.entity.shadowstagerange[0] = self.entity.shadowstagerange[0] + self.value
		self.entity.shadowstagerange[1] = self.entity.shadowstagerange[1] + self.value
		self.entity.shadowstagerange[2] = self.entity.shadowstagerange[2] + self.value
		self.entity.shadowstagerange[3] = self.entity.shadowstagerange[3] + self.value
	end
	if window:KeyHit(Key.Down)==true then
		self.entity.shadowstagerange[0] = self.entity.shadowstagerange[0] - self.value
		self.entity.shadowstagerange[1] = self.entity.shadowstagerange[1] - self.value
		self.entity.shadowstagerange[2] = self.entity.shadowstagerange[2] - self.value
		self.entity.shadowstagerange[3] = self.entity.shadowstagerange[3] - self.value
	end
end

function Script:PostRender(context)
	context:SetBlendMode(1)
	for i = 0, 3 do
		context:DrawText("Range: "..self.entity.shadowstagerange[i],2,i*22)
	end
	context:SetBlendMode(0)
end

 

[Rick]

It seems:

 

36

45

60

110

 

Are the ranges I need to set to get the best look. I have no idea how any of this works but thanks for the script to help me see what gives what visual Mac!

[macklebee]

Are you asking what CSMs are?

https://msdn.microsoft.com/en-us/library/windows/desktop/ee416307(v=vs.85).aspx

[Yue]

@Josh @Rick @macklebee

[Daemoc]

How fortuitous. I just ran into this issue myself.

Thanks for the script mac!