Getting acquainted with Craft

Codea Craft
1

Most of my time to date has been spent out of Codea Craft…but I’d like to start delving more into using Shade in Codea. I’d like to first explore using shaders in 2D…or at least fake it with a top-down camera.

My first question is really just a sanity check: am I right that good ol’ rotate(), scale(), and translate() have no effect on the drawing of the Craft scene? Do I just have to replicate that behavior with camera movement?

2

@brianolive In Craft, you move the camera. Here’s a small example of attaching the camera to a moving object. Tilt the device left or right to turn.

displayMode(FULLSCREEN)

function setup()
    bx,bz=0,0   -- initial block position
    vel=.2      -- velocity
    dir=0
    
    scene = craft.scene()
       
    ground=scene:entity()
    ground.model = craft.model.cube(vec3(1000,1,1000))
    ground.position=vec3(0,-10,0)
    ground.material = craft.material("Materials:Basic")
    ground.material.map = readImage("Surfaces:Desert Cliff Color")
    ground.material.offsetRepeat=vec4(0,0,50,50)
    
    block = scene:entity()
    block.model = craft.model.cube(vec3(4,.5,2))
    block.material = craft.material("Materials:Standard")
    block.material.map = readImage("Blocks:Trunk White Top")
    block.position=vec3(0,0,0)

    cam = scene:entity()
    cam.model = craft.model.cube(vec3(.2,.2,.2))
    cam.material = craft.material("Materials:Specular")
    cam.material.map = readImage("Blocks:Brick Grey")
    cam.position=vec3(0,10,6)    
    
    cam.parent=block    -- attach camera to block
    c=cam:add(craft.camera, 120, .1, 1000, false) -- set camera values
    c.entity.eulerAngles=vec3(0,180,0)  -- set camera pointing direction
end

function update(dt)
    scene:update(dt)
    
    block.eulerAngles = vec3(0,dir,0)
    bx=bx-vel*math.sin(math.rad(dir))   -- calculate x value
    bz=bz-vel*math.cos(math.rad(dir))   -- calculate z value
    block.position=vec3(bx,0,bz)        -- update block x,z position   
    
    c.entity.eulerAngles=vec3(20,180,-Gravity.x*100)  -- camera pointing direction
end

function draw()
    update(DeltaTime)
    scene:draw()	
    dir=dir-Gravity.x*3
end
3

@brianolive Here’s another Craft example. Slide your finger around the screen. You’re not really moving the box, but the camera.

displayMode(FULLSCREEN)

function setup()
    assert(OrbitViewer, "Please include Cameras (not Camera) as a dependency")
    scene = craft.scene()
    scene.camera:add(OrbitViewer, vec3(0,0,0), 100, 0, 500)
    c=scene:entity()
    c.position=vec3(0,0,0)
    c.model = craft.model.cube(vec3(25,10,10))
    c.material = craft.material("Materials:Standard")
    c.material.map = readImage("Blocks:Trunk White Top")
end

function draw()
    update(DeltaTime)
    scene:draw()    
    text("Drag your finger on the screen to rotate the cube",WIDTH/2,HEIGHT-100)
end

function update(dt)
    scene:update(dt)
end
4

Thanks @dave1707 , much appreciated!