VNEUI is a lightweight, renderer-agnostic UI toolkit written in Odin. It is built alongside the Vnefall engine and designed to power VN-style menus and tools without hardcoding layouts.

This library is intended to stay simple, flexible, and easy to integrate with custom renderers.

• Clean, minimal core (no heavy dependencies)
• Renderer-agnostic drawing backend
• Flexible layout and theming
• Works for game UI and editor/debug tools

Active development. See roadmap.md for milestones and docs/usage.md for usage.

1. Add the collection when building:

odin run your_app -collection:vneui=./vneui

2. Import it in code:

import "vneui:src"

3. Initialize and render per frame:

ctx: vneui.UI_Context
vneui.ui_init(&ctx)
defer vneui.ui_shutdown(&ctx)

for running {
    input := vneui.UI_Input{
        mouse_pos = vneui.Vec2{mx, my},
        mouse_down = mouse_down,
        mouse_pressed = mouse_pressed,
        mouse_released = mouse_released,
        scroll_y = wheel_delta,
        delta_time = dt,
        text_input = typed_text,
    }

    theme := vneui.ui_theme_default(0, 18)
    vneui.ui_begin_frame(&ctx, input, theme)

    vneui.ui_panel_begin(&ctx, vneui.Rect{40, 40, 320, 240}, .Column, 12, 8)
    vneui.ui_label_layout(&ctx, "Hello VNEUI", 0, 24)
    _ = vneui.ui_button_layout(&ctx, "Click", 0, 36)
    vneui.ui_panel_end(&ctx)

    commands := vneui.ui_end_frame(&ctx)
    // Render commands here
}

For full examples, see docs/usage.md.

• Draw command list (rects, rounded rects, borders, lines, text, images, scissor)
• Layout stack (row/column/stack/grid) with padding + gap
• Theme + style overrides (colors, borders, fonts, alignment, shadows)
• Core widgets: panel, label, button, toggle, slider
• Text input + dropdown/select
• Text wrapping helper
• Scroll container helper
• Scroll momentum + scrollbar helper
• Nine-slice image helper
• Keyboard navigation + focus helpers
• Menu helpers (main menu, preferences, save/load, confirm)
• Modals, tooltips, toasts, transitions
• SVG demo exporter (see vneui/demo/)

For accurate text wrapping, set ctx.measure_text to your renderer's text-width function. If unset, VNEUI uses a simple character-width fallback.

Generate a visual SVG demo:

odin run vneui/demo -collection:vneui=./vneui

Vnefall needs a UI system that supports:

• VN menus and preferences
• Save/Load screens
• Tooling and debug overlays

VNEUI aims to be reusable beyond Vnefall as the API stabilizes.