github.com/gogpu/ui - theme/material3/theme.go

func AsTheme

AsTheme converts the Material 3 theme to a [theme.Theme] for use with

the generic theme system. This maps M3 color roles to the shared

[theme.ColorPalette] structure, preserving background, surface, and

on-color relationships.

Use this when you need to pass an M3 theme to APIs that accept

[*theme.Theme], such as [app.WithTheme] or [app.App.SetTheme]:

m3 := material3.New(widget.Hex(0x6750A4))

uiApp := app.New(app.WithTheme(m3.AsTheme()))

func (t *Theme) AsTheme() *theme.Theme {
	cs := t.Colors
	mode := theme.ModeLight
	name := "Material 3"
	shadows := theme.DefaultShadowsLight()
	if t.dark {
		mode = theme.ModeDark
		name = "Material 3 Dark"
		shadows = theme.DefaultShadowsDark()
	}

	return &theme.Theme{
		Name:	name,
		Mode:	mode,
		Colors: theme.ColorPalette{
			Primary:	cs.Primary,
			PrimaryLight:	cs.PrimaryContainer,
			PrimaryDark:	cs.OnPrimaryContainer,
			Secondary:	cs.Secondary,
			SecondaryLight:	cs.SecondaryContainer,
			SecondaryDark:	cs.OnSecondaryContainer,
			Background:	cs.Background,
			Surface:	cs.Surface,
			SurfaceVariant:	cs.SurfaceVariant,
			Error:		cs.Error,
			Warning:	cs.Error,	// M3 has no dedicated warning role
			Success:	cs.Tertiary,
			Info:		cs.Primary,
			OnPrimary:	cs.OnPrimary,
			OnSecondary:	cs.OnSecondary,
			OnBackground:	cs.OnBackground,
			OnSurface:	cs.OnSurface,
			OnError:	cs.OnError,
			Divider:	cs.OutlineVariant,
			Outline:	cs.Outline,
			Shadow:		widget.RGBA(0, 0, 0, 0.20),
		},
		Typography:	theme.DefaultTypography(),
		Spacing:	theme.DefaultSpacing(),
		Shadows:	shadows,
		Radii:		theme.DefaultRadii(),
		Extensions:	make(map[string]any),
	}
}

func IsDark

IsDark returns true if this theme uses a dark color scheme.

func (t *Theme) IsDark() bool {
	return t.dark
}

func New

New creates a Material 3 theme from a seed color.

The seed color drives the entire color scheme. Material 3 derives

primary, secondary, tertiary, neutral, and error palettes from

this single seed using HCT (Hue, Chroma, Tone) color science.

By default, the theme uses a light color scheme. Use [NewDark] for

a dark scheme, or access [Light] and [Dark] functions to generate

color schemes independently.

func New(seedColor widget.Color) *Theme {
	return &Theme{
		Colors:		Light(seedColor),
		Typography:	DefaultTypeScale(),
		Shape:		DefaultShapeScale(),
	}
}

func NewDark

NewDark creates a Material 3 theme with a dark color scheme from a seed color.

This is equivalent to New but uses dark mode tonal mappings.

func NewDark(seedColor widget.Color) *Theme {
	return &Theme{
		Colors:		Dark(seedColor),
		Typography:	DefaultTypeScale(),
		Shape:		DefaultShapeScale(),
		dark:		true,
	}
}

func OnSurface

OnSurface returns the default text/icon color for surface backgrounds.

In Material 3, this is the OnSurface color role derived from the

neutral tonal palette. It provides the highest contrast on surface

backgrounds for body text and icons.

func (t *Theme) OnSurface() widget.Color {
	return t.Colors.OnSurface
}

type Theme struct

Theme provides Material 3 (Material You) design tokens.

A Theme contains the complete set of design tokens needed to style

a Material 3 application: colors, typography, and shape. It is

generated from a single seed color, which is used to derive a full

harmonious color scheme.

Create a theme with [New]:

theme := material3.New(widget.Hex(0x6750A4))

primary := theme.Colors.Primary

fontSize := theme.Typography.BodyMedium.FontSize

radius := theme.Shape.Medium

type Theme struct {
	// Colors holds the Material 3 color scheme derived from the seed color.
	Colors	ColorScheme

	// Typography holds the Material 3 type scale.
	Typography	TypeScale

	// Shape holds the Material 3 corner radius scale.
	Shape	ShapeScale

	// dark indicates whether this theme uses a dark color scheme.
	dark	bool
}

theme/material3/theme.go

Functions