Let’s get into some technical details about how a layout engine works. We assume that we have a tree of elements that comprise the UI. Starting from the root node, we request […]
Core Layout Protocol API (UI Engine)
Fitting an image to its element frame
Images require various sizing modes to fit in a responsive layout. Here we’ll look at the relationship between the element and visual and the basic sizing options. I’ll also look at […]
What is a “box model”? (UI Element layout)
A box model describes how to measure an element for layout. It defines what size is and how it relates to the content, margin and padding. It may seem trivial, but clear […]
What is responsive layout?
A good UI design must accommodate the various device formats and resolutions that users have. Element placement cannot be absolute, but rather be constrained and expanded by the available space. Layouts […]
UI Engine Layout: Additive, Partitioned and Layered
Layout determines how children are positioned and sized within their parent element. There are three approaches to placing child elements within a parent: Additive: The children combine to define the size […]
UI Layout: Working with Pixels, Points and Density
Devices have various physical resolutions and densities. One phone may be 10cm wide and have 800pixels across, while another may be 8cm wide and have 1200pixels across. A UI engine needs to […]
UI Layout: Natural versus dependent size
Elements have either a natural size, a dependent size, or combination of the two. The size of an element influences its placement. The user and creator of a UI layout system must […]
Yummy UI food with keyframe animations
When I saw the below demo I thought “neat, how’d they do that”? That may sound surprising if you knew that I wrote the API for this. In this article I’ll describe […]
A game of what’d they press? Hit testing in a 2d/3d layout
A simple tap of the screen invokes a staggering amount of calculations. That screen is actually big tree of UI elements, and we need to navigate it quickly to find the right […]
