Cube

What is it

Convert perspective square to perspective cube

How does it work

• Finds perspective vanishing points
• Uses law of ratios to find correct volume
• Returns 2d-Points of the cube bounds

How do I get it

• Carthage github "eonist/Cube"
• Manual Open Cube.xcodeproj
• CocoaPod (Coming soon)

Example:

let corners:[CGPoint] = [.init(x:100,y:130),.init(x:220,y:150),.init(x:200,y:220),.init(x:130,y:240)]
let quad:Quad = (corners[0],corners[1],corners[3],corners[2])
let cube:Cube = CubeUtil.cube(quad:quad)
let cubeGraphic:CubeGraphic = .init()
layer.addSublayer(cubeGraphic)
cubeGraphic.drawCube(cube: cube)

References:

• Mapping images to Quadrilaterals https://github.com/paulz/PerspectiveTransform
• Mapping image to Quad pt.2 https://github.com/agens-no/AGGeometryKit
• CATransform3d Cube: google book
• Build a cube using CATransform3D: https://www.cocoanetics.com/2012/08/cubed-coreanimation-conundrum/
• JS Quad mapping: http://jsfiddle.net/dFrHS/3/
• Vanishing point logic: https://www.handprint.com/HP/WCL/perspect4.html
• Vanishing point problem: https://math.stackexchange.com/questions/1418293/determine-cube-orientation-given-one-side-in-a-perspective-projection?rq=1
• AR resources: https://github.com/olucurious/Awesome-ARKit
• GetPerspectiveTransform: http://answers.opencv.org/question/5018/getperspectivetransform-mathematical-explanation/

Todo:

• Add support for 1 point perspective Quadrilaterals ✅
• Add support for horizontal 1p quads (co-linear, epsilon etc) ✅
• Add support for square w/o perspective ✅
• Optimize the math for performance 👈
• Account for object relation to POV 👈