Rendering API

The Rendering API allows you to draw 2D geometry and text on the screen, as well as 3D geometry in the world.

Rendering Events

2D Rendering

All 2D drawing must happen within the prepare_ui_canvas event handler.

feature.on("prepare_ui_canvas", function(event)
    local canvas = event.canvas
    -- Draw here
end)

2D Shadow Rendering

To draw shadows for 2D drawables (like rect_drawable), draw them on the shadow canvas within the prepare_shadow_canvas event handler.

feature.on("prepare_shadow_canvas", function(event)
    local canvas = event.canvas
    -- Draw shadow geometries here
end)

3D Rendering

All 3D world drawing must happen within the prepare_world_canvas event handler.

feature.on("prepare_world_canvas", function(event)
    local canvas = event.canvas
    -- Draw here
end)

Drawable Types (2D)

The following builders are available under types.* for use with ui_canvas.

Rectangles (rect_drawable)

types.rect_drawable.new()
     .position(10, 10)
     .bounds(100, 50)
     .base_color(types.color.BLACK)
     .corner_radii(5)
     .outline(1, types.color.WHITE)
     .insert(canvas)

Text (text_drawable)

types.text_drawable.new()
     .text("Hello Neon")
     .position(10, 70)
     .scale(12)
     .align(enums.align.left)
     .insert(canvas)

Circles (circle_drawable)

types.circle_drawable.new()
     .position(150, 35)
     .size(20)
     .base_color(types.color.RED)
     .insert(canvas)

Lines (line_drawable)

types.line_drawable.new()
     .color(types.color.WHITE)
     .point(10, 100)
     .point(110, 150)
     .insert(canvas)

Canvas Utilities

Scissor Mask (push_scissor_mask)

Clips all rendering within the callback to the specified rectangle.

canvas.push_scissor_mask(x, y, width, height, function()
    -- Everything drawn here will be clipped to the rectangle
end)

Drawable Types (3D)

The following builders are available under types.* for use with world_canvas.

3D Boxes (world_box_drawable)

types.world_box_drawable.new()
     .min(x1, y1, z1)
     .max(x2, y2, z2)
     .fill_color(types.color.BLUE)
     .outline_color(types.color.WHITE)
     .insert(canvas)

3D Lines (world_line_drawable)

types.world_line_drawable.new()
     .color(types.color.RED)
     .point(x1, y1, z1)
     .point(x2, y2, z2)
     .insert(canvas)

3D Flat Circles (world_flat_circle_drawable)

types.world_flat_circle_drawable.new()
     .center(x, y, z)
     .radius(5)
     .fill_color(types.color.GREEN)
     .insert(canvas)