Engine » UI » Canvas module

Architecture

The two main UI components are UIElement and UICanvas. For it to work properly, each UIElement must be a child of a UICanvas, or of another UIElement.

Each UIElement generates a list of drawing commands, UIDrawList, that are then pooled together by the UICanvas at the root of the hierarchy.

Each entry in a draw list contains a UIDrawList::Type and a UIDrawList::Command. The Type holds information that is common for all similar commands, and the Command contains the specifics to that one command. Each entry also has a raw data buffer to hold the data the command needs to pass to the shaders.

After aggregating the draw commands, the UICanvas draws them, grouped by type.

Check out UI for the an example of the UI plugin in use.

Files

file canvas.hpp

Component cubos::engine::UICanvas.

file draw_list.hpp

Class cubos::engine::UIDrawList.

file element.hpp

Component cubos::engine::UIElement.

file expand.hpp

Component cubos::engine::UIExpand.

file horizontal_stretch.hpp

Component cubos::engine::UIHorizontalStretch.

file keep_pixel_size.hpp

Component cubos::engine::UIKeepPixelSize.

file match_height.hpp

Component cubos::engine::UIMatchHeight.

file match_width.hpp

Component cubos::engine::UIMatchWidth.

file native_aspect_ratio.hpp

Component cubos::engine::UINativeAspectRatio.

file plugin.hpp

Plugin entry point.

file vertical_stretch.hpp

Component cubos::engine::UIVerticalStretch.

Classes

struct cubos::engine::UICanvas

Component which represents a target for UI rendering.

class cubos::engine::UIDrawList

Holds a collections of draw commands and their data.

struct cubos::engine::UIDrawList::Type

Describes a UI draw call type.

struct cubos::engine::UIDrawList::Command

Describes a UI draw instruction.

struct cubos::engine::UIDrawList::Entry

Describes a draw commands and how it fits into the draw list carrying it.

class cubos::engine::UIDrawList::EntryBuilder

Builds an Entry.

struct cubos::engine::UIElement

Component which defines the space an element of the UI occupies as a rect.

struct cubos::engine::UIExpand

Component which makes a UI canvas scale to maintain proportions, choosing the dimension which reduces the element sizes on screen.

struct cubos::engine::UIHorizontalStretch

Component which makes a UI element fit horizontally to its parent.

struct cubos::engine::UIKeepPixelSize

Component which makes a UI canvas scale to keep its elements at the same pixel size.

struct cubos::engine::UIMatchHeight

Component which makes a UI canvas scale to maintain vertical proportions.

struct cubos::engine::UIMatchWidth

Component which makes a UI canvas scale to maintain horizontal proportions.

struct cubos::engine::UINativeAspectRatio

Component which makes a UI element keep the aspect ratio of its source.

struct cubos::engine::UIVerticalStretch

Component which makes a UI element fit vertically to its parent.

Functions

auto uiCanvasPlugin(Cubos& cubos) -> CUBOS_ENGINE_API void

Plugin entry function.

Function documentation