CreateInterface

This function creates a new graphical user interface for desktop applications or in-game interfaces.

Syntax

Interface CreateInterface(Window window)
Interface CreateInterface(World world, Font font, iVec2 size)

Returns

Returns a new interface object.

Example

Several examples are shown below to demonstrate different types of programs you can create.

The first example shows how to create an interface directly on a window for an event-based desktop application.

--Get the displays
local displays = GetDisplays()

--Create window
local window = CreateWindow("Ultra Engine", 0, 0, 1280, 720, displays[1])

--Create user interface
local ui = CreateInterface(window)

--Create widget
local sz = ui.background:ClientSize()
local button = CreateButton("Button", sz.x / 2 - 75, sz.y / 2 - 15, 150, 30, ui.background)

while (true) do
    local ev = WaitEvent()
    if (ev.id == EVENT_WINDOWCLOSE and ev.source == window) then
        return 0
    end
end

The second example shows how to create an interface that appears in a 3D rendering viewport. Note that in this example you must send events to the interface with the ProcessEvent method.

--Get the displays
local displays = GetDisplays()

--Create window
local window = CreateWindow("Ultra Engine", 0, 0, 1280, 720, displays[1])

--Create framebuffer
local framebuffer = CreateFramebuffer(window)

--Create world
local world = CreateWorld()

--Load a font
local font = LoadFont("Fonts/arial.ttf")

--Create user interface
local ui = CreateInterface(world, font, framebuffer.size)

--Create widget
local sz = ui.background:ClientSize()
local button = CreateButton("Button", sz.x / 2 - 75, sz.y / 2 - 15, 150, 30, ui.background)

--Create camera
local camera = CreateCamera(world, PROJECTION_ORTHOGRAPHIC)
camera:SetPosition(framebuffer.size.x * 0.5, framebuffer.size.y * 0.5, 0)

while not window:KeyDown(KEY_ESCAPE) do
    while (PeekEvent()) do
        local ev = WaitEvent()
        if (ev.id == EVENT_WINDOWCLOSE and ev.source == window) then
            return 0
        else
            ui:ProcessEvent(ev)
        end
    end

    world:Update()
    world:Render(framebuffer)
end

This example shows how to create an interactive user interface that is displayed on a 3D surface:

-- Get the displays
local displays = GetDisplays()

-- Create window
local window = CreateWindow("Ultra Engine", 0, 0, 1280, 720, displays[1])

-- Create framebuffer
local framebuffer = CreateFramebuffer(window)

-- Create world
local world = CreateWorld()

-- Load a font
local font = LoadFont("Fonts/arial.ttf")

-- Create a camera
local camera = CreateCamera(world)
camera:SetPosition(0, 0, -2)
camera:SetClearColor(0.125)

-- Camera controls
require "Components/Player/CameraControls"
camera:AddComponent(CameraControls)

-- Create a model
local box = CreateBox(world)
box:SetRotation(0, 45, 0)
box:SetPickMode(PICK_MESH)

-- Create light
local light = CreateBoxLight(world)
light:SetRotation(45, 35, 0)
light:SetRange(-10, 10)
light:SetColor(Vec4(4, 4, 4, 1))

-- Create user interface
local ui = CreateInterface(world, font, iVec2(256))
ui:SetRenderLayers(2)

-- Create widget
local sz = ui.background:ClientSize()
local button = CreateButton("Button", sz.x / 2 - 75, sz.y / 2 - 15, 150, 30, ui.background)

-- Create camera
local uicamera = CreateCamera(world, PROJECTION_ORTHOGRAPHIC)
uicamera:SetClearColor(1, 0, 0, 1)
uicamera:SetPosition(128.0, 128.0, 0)
uicamera:SetRenderLayers(2)
uicamera:SetRealtime(false)

local texbuffer = CreateTextureBuffer(256, 256)
uicamera:SetRenderTarget(texbuffer)

local mtl = CreateMaterial()
mtl:SetTexture(texbuffer:GetColorAttachment(1))
box:SetMaterial(mtl)

while not window:Closed() and not window:KeyDown(KEY_ESCAPE) do
    while PeekEvent() do
        local ev = WaitEvent()
        if ev.id == EVENT_MOUSEDOWN or ev.id == EVENT_MOUSEUP or ev.id == EVENT_MOUSEMOVE then
            local pick = camera:Pick(framebuffer, ev.position.x, ev.position.y, 0, true)
            if pick.entity == box then
                ev.position.x = Round(pick.texcoords[1].x * 256.0)
                ev.position.y = Round(pick.texcoords[1].y * 256.0)
                ui:ProcessEvent(ev)
                uicamera:Render()
            end
        end
    end

    world:Update()
    world:Render(framebuffer)
end

This example shows how to use two cameras to display a GUI on top of a 3D world.

--Get the displays
local displays = GetDisplays()

--Create window
local window = CreateWindow("Ultra Engine", 0, 0, 1280, 720, displays[1])

--Create framebuffer
local framebuffer = CreateFramebuffer(window)

--Create world
local world = CreateWorld()

--Create camera
local camera = CreateCamera(world)
camera:SetClearColor(0.125)
camera:Move(0,0,-4)

--Create a model
local box = CreateBox(world)

--Create a light
local light = CreateBoxLight(world);
light:SetRotation(45, 35, 0)
light:SetRange(-10,10)
light:SetArea(10,10)

--Load a font
local font = LoadFont("Fonts/arial.ttf")

--Create user interface
local ui = CreateInterface(world, font, framebuffer.size)
ui:SetRenderLayers(2)
ui.background:SetColor(0,0,0,0.5)

--Create widget
local sz = ui.background:ClientSize()
local button = CreateButton("Button", sz.x / 2 - 75, sz.y / 2 - 15, 150, 30, ui.background)

--Create a camera for the UI
local uicam = CreateCamera(world, PROJECTION_ORTHOGRAPHIC)
uicam:SetPosition(framebuffer.size.x * 0.5, framebuffer.size.y * 0.5, 0)
uicam:SetClearMode(CLEAR_DEPTH)
uicam:SetRenderLayers(2)

while not window:KeyDown(KEY_ESCAPE) do
    while (PeekEvent()) do
        local ev = WaitEvent()
        if (ev.id == EVENT_WINDOWCLOSE and ev.source == window) then
            return 0
        else
            ui:ProcessEvent(ev)
        end
    end

    box:Turn(0,1,0)
    world:Update()
    world:Render(framebuffer)
end