2D Drawing to a Texture

[Josh]

Some people have asked me how to do this.  Here is an example:

local window=Window:Create("Draw to texture")

--Create the graphics context
context=Context:Create(window,0)
if context==nil then return end

--Create a world
world=World:Create()

local camera = Camera:Create()
camera:Move(0,0,-2)

local buffer = Buffer:Create(512,512,1,0)

local box = Model:Box()

local mtl = Material:Create()
mtl:SetTexture(buffer:GetColorTexture())
mtl:SetShader("Shaders/Model/diffuse.shader")
--local surf = box:GetSurface(0)
box:SetMaterial(mtl)
mtl:Release()

local font = Font:Load("Fonts/Arial.ttf",42)
context:SetFont(font)
font:Release()

world:SetAmbientLight(1,1,1)

while window:Closed()==false do
	
	box:Turn(0,0.2,0)
	Time:Update()
	world:Update()
	
	--Render to texture
	buffer:Enable()
	buffer:SetColor(0,0,1)
	buffer:Clear()
	buffer:SetColor(1,0,0)
	context:DrawRect(0,0,256,256)
	context:DrawRect(256,256,256,256)
	context:SetColor(1,1,1)
	context:SetBlendMode(Blend.Alpha)
	context:DrawText("Draw to texture! ;)",0,0,512,512,Text.Center+Text.VCenter)
	context:SetBlendMode(Blend.Solid)

	--Render world
	context:Enable()
	world:Render()
	context:Sync()
end

[Josh]

You could call Texture:BuildMipmaps() to improve the appearance of the texture after drawing.

[macklebee]

Similar examples from over the years: 

 

[macklebee]

1 hour ago, jen said:

Useful for minimaps!

yep - same concept: 

 

[mdgunn]

 

16 hours ago, jen said:

Useful for minimaps!

Never got round to mini maps yet so out of interest is the mechanism presented here the most obvious choice to go with or what are 1 or 2 other ways that might be considered?  

I imagine it depends on your game of course (as always) so I suppose I mean in most cases what methods might have been used?