12. Mesh

12. Mesh

function setup()
    --set up normal sprite
    img=readImage("Tyrian Remastered:Space Ice 3")
    w,h=img.width,img.height
    --set up mesh alternative
    g=mesh()
    g.texture="Tyrian Remastered:Flame 2"  --name of the image we want to use
    parameter.boolean("Mesh",false)
    parameter.integer("NumberOfObjects",50,200,50)
end

function draw()
    background(0)
    output:clear()
    print("This demo shows how to draw images using a mesh, rather than sprites, for speed.")
    print("NB You won't see an obvious speed change when you switch between them, because this hasn't been set up as a speed test.")    
    
    if Mesh==false then  --sprites
        for i=1,NumberOfObjects do
            --position and size randomly
            sprite(img,math.random(0,WIDTH),math.random(0,HEIGHT-100),w*(math.random()*.4))
        end        
    else               --Mesh
        g:clear()
        for i=1,NumberOfObjects do
            local x=math.random()*.4 --pick a random size, as we did for sprites
            --add a rectangle the same size as our sprite
            local d=g:addRect(math.random(0,WIDTH),math.random(0,HEIGHT-100),w*x,h*x)
            --the numbers 0,0,1,1 mean to use the whole image, explanation in a later demo
            g:setRectTex(d,0,0,1,1) --apply the texture, ie image, but don't draw anything yet
        end
        g:draw() --draw the final result
    end
end