Ilia Denisov
696 lines
18 KiB
Go
696 lines
18 KiB
Go
package world
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import (
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"image"
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"image/color"
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"sync"
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)
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// StyleID references a fully-materialized style stored in StyleTable.
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type StyleID int
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const (
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// StyleIDInvalid means "no style". It should not be used for rendering.
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StyleIDInvalid StyleID = 0
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// Built-in default styles (stable IDs).
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StyleIDDefaultLine StyleID = 1
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StyleIDDefaultCircle StyleID = 2
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StyleIDDefaultPoint StyleID = 3
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)
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// Default priorities (smaller draws earlier), step=100.
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const (
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DefaultPriorityLine = 100
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DefaultPriorityCircle = 200
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DefaultPriorityPoint = 300
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)
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var (
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transparentColor color.Color = &color.RGBA{A: 0}
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)
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// TransparentFill returns a reusable fully transparent color value.
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//
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// It is intended for callers that want to explicitly disable fill while still
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// setting a non-nil FillColor override.
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func TransparentFill() color.Color { return transparentColor }
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// Style is a fully resolved style used by the renderer.
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// All fields are concrete values; no "optional" markers here.
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// Optionality is handled by StyleOverride during style creation.
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type Style struct {
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// FillColor is used for Fill() operations (points/circles typically).
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// If nil, the renderer may treat it as "do not fill" depending on primitive.
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FillColor color.Color
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// StrokeColor is used for Stroke() operations (lines typically).
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// If nil, the renderer may treat it as "do not stroke" depending on primitive.
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StrokeColor color.Color
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// StrokeWidthPx is a screen-space stroke width in pixels.
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StrokeWidthPx float64
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// StrokeDashes is the dash pattern in pixels. nil/empty means "solid".
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StrokeDashes []float64
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// StrokeDashOffset is the dash phase in pixels.
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StrokeDashOffset float64
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// PointRadiusPx is a screen-space radius for Point markers.
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PointRadiusPx float64
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}
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// StyleOverride describes partial modifications applied to a base Style.
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// Fields set to nil mean "do not override".
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type StyleOverride struct {
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FillColor color.Color
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StrokeColor color.Color
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StrokeWidthPx *float64
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StrokeDashes *[]float64
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StrokeDashOffset *float64
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PointRadiusPx *float64
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}
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// IsZero reports whether override does not specify any fields.
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func (o StyleOverride) IsZero() bool {
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return o.FillColor == nil &&
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o.StrokeColor == nil &&
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o.StrokeWidthPx == nil &&
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o.StrokeDashes == nil &&
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o.StrokeDashOffset == nil &&
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o.PointRadiusPx == nil
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}
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// Apply applies override to base style and returns a new fully resolved style.
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// It copies slices defensively to avoid aliasing.
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func (o StyleOverride) Apply(base Style) Style {
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out := base
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if o.FillColor != nil {
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out.FillColor = o.FillColor
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}
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if o.StrokeColor != nil {
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out.StrokeColor = o.StrokeColor
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}
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if o.StrokeWidthPx != nil {
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out.StrokeWidthPx = *o.StrokeWidthPx
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}
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if o.StrokeDashes != nil {
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// Copy to avoid future mutation by caller.
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src := *o.StrokeDashes
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if src == nil {
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out.StrokeDashes = nil
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} else {
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dst := make([]float64, len(src))
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copy(dst, src)
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out.StrokeDashes = dst
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}
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}
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if o.StrokeDashOffset != nil {
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out.StrokeDashOffset = *o.StrokeDashOffset
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}
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if o.PointRadiusPx != nil {
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out.PointRadiusPx = *o.PointRadiusPx
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}
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return out
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}
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// StyleTable stores fully resolved styles and provides stable lookups by StyleID.
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// It also holds three built-in defaults for Line/Circle/Point.
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type StyleTable struct {
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mu sync.RWMutex
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nextID StyleID
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styles map[StyleID]Style
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}
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// NewStyleTable creates a new style table with built-in default styles.
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// The default values are intentionally simple and stable.
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func NewStyleTable() *StyleTable {
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t := &StyleTable{
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nextID: StyleIDDefaultPoint + 1,
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styles: make(map[StyleID]Style, 16),
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}
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// Defaults: conservative, deterministic.
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// Colors: opaque black. (Callers can override.)
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white := color.RGBA{R: 255, G: 255, B: 255, A: 255}
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t.styles[StyleIDDefaultLine] = Style{
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FillColor: nil,
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StrokeColor: white,
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StrokeWidthPx: 2.0,
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StrokeDashes: nil,
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StrokeDashOffset: 0,
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PointRadiusPx: 0,
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}
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t.styles[StyleIDDefaultCircle] = Style{
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FillColor: white,
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StrokeColor: nil,
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StrokeWidthPx: 0,
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StrokeDashes: nil,
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StrokeDashOffset: 0,
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PointRadiusPx: 0,
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}
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t.styles[StyleIDDefaultPoint] = Style{
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FillColor: white,
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StrokeColor: nil,
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StrokeWidthPx: 0,
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StrokeDashes: nil,
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StrokeDashOffset: 0,
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PointRadiusPx: 2.0,
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}
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return t
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}
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// Get returns a style by id.
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func (t *StyleTable) Get(id StyleID) (Style, bool) {
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t.mu.RLock()
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defer t.mu.RUnlock()
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s, ok := t.styles[id]
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if !ok {
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return Style{}, false
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}
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// Defensive copy of slices.
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if s.StrokeDashes != nil {
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cp := make([]float64, len(s.StrokeDashes))
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copy(cp, s.StrokeDashes)
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s.StrokeDashes = cp
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}
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return s, true
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}
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// AddDerived creates a new style based on baseID with an override applied.
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// It returns the new style ID.
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func (t *StyleTable) AddDerived(baseID StyleID, override StyleOverride) StyleID {
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t.mu.Lock()
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defer t.mu.Unlock()
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base, ok := t.styles[baseID]
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if !ok {
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panic("StyleTable.AddDerived: unknown base style ID")
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}
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derived := override.Apply(base)
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id := t.nextID
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t.nextID++
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// Defensive copy of slices on store.
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if derived.StrokeDashes != nil {
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cp := make([]float64, len(derived.StrokeDashes))
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copy(cp, derived.StrokeDashes)
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derived.StrokeDashes = cp
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}
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t.styles[id] = derived
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return id
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}
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// AddStyle stores a fully resolved style as a new StyleID.
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// It defensively copies slice fields.
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func (t *StyleTable) AddStyle(s Style) StyleID {
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t.mu.Lock()
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defer t.mu.Unlock()
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id := t.nextID
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t.nextID++
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if s.StrokeDashes != nil {
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cp := make([]float64, len(s.StrokeDashes))
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copy(cp, s.StrokeDashes)
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s.StrokeDashes = cp
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}
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t.styles[id] = s
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return id
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}
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// Count returns the number of styles stored in the table.
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// Intended for tests/diagnostics.
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func (t *StyleTable) Count() int {
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t.mu.RLock()
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defer t.mu.RUnlock()
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return len(t.styles)
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}
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// BackgroundTileMode defines how the background image is tiled.
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type BackgroundTileMode uint8
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const (
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BackgroundTileNone BackgroundTileMode = iota
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BackgroundTileRepeat
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)
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// BackgroundAnchorMode defines whether the background image scrolls with the world or stays fixed to viewport.
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type BackgroundAnchorMode uint8
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const (
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BackgroundAnchorWorld BackgroundAnchorMode = iota
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BackgroundAnchorViewport
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)
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// BackgroundScaleMode defines how the background image is scaled.
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// (Step 1: defined for API completeness; used later when rendering background image.)
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type BackgroundScaleMode uint8
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const (
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BackgroundScaleNone BackgroundScaleMode = iota
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BackgroundScaleFit
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BackgroundScaleFill
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)
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// StyleTheme describes a cohesive style set (theme) for rendering.
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// Step 1: we store it in World and use it for background and default base styles.
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// Step 2+: theme-relative overrides and background image drawing.
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type StyleTheme interface {
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ID() string
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Name() string
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BackgroundColor() color.Color
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BackgroundImage() image.Image
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BackgroundTileMode() BackgroundTileMode
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BackgroundScaleMode() BackgroundScaleMode
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BackgroundAnchorMode() BackgroundAnchorMode
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PointStyle() Style
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LineStyle() Style
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CircleStyle() Style
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// Class overrides (relative to base kind style).
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// Return (override, true) when class is supported; (zero, false) means "no override".
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PointClassOverride(class PointClassID) (StyleOverride, bool)
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LineClassOverride(class LineClassID) (StyleOverride, bool)
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CircleClassOverride(class CircleClassID) (StyleOverride, bool)
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}
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// DefaultTheme is a conservative theme matching built-in default styles.
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type DefaultTheme struct{}
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func (DefaultTheme) ID() string { return "default" }
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func (DefaultTheme) Name() string { return "Default" }
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func (DefaultTheme) BackgroundColor() color.Color { return color.RGBA{A: 255} }
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func (DefaultTheme) BackgroundImage() image.Image { return nil }
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func (DefaultTheme) BackgroundTileMode() BackgroundTileMode { return BackgroundTileNone }
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func (DefaultTheme) BackgroundScaleMode() BackgroundScaleMode { return BackgroundScaleNone }
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func (DefaultTheme) BackgroundAnchorMode() BackgroundAnchorMode { return BackgroundAnchorWorld }
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func (DefaultTheme) PointStyle() Style {
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s, _ := NewStyleTable().Get(StyleIDDefaultPoint)
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return s
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}
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func (DefaultTheme) LineStyle() Style {
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s, _ := NewStyleTable().Get(StyleIDDefaultLine)
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return s
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}
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func (DefaultTheme) CircleStyle() Style {
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s, _ := NewStyleTable().Get(StyleIDDefaultCircle)
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return s
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}
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func (DefaultTheme) PointClassOverride(PointClassID) (StyleOverride, bool) {
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return StyleOverride{}, false
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}
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func (DefaultTheme) LineClassOverride(LineClassID) (StyleOverride, bool) {
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return StyleOverride{}, false
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}
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func (DefaultTheme) CircleClassOverride(CircleClassID) (StyleOverride, bool) {
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return StyleOverride{}, false
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}
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// This file provides two sample themes for demos and UI integration:
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// LightTheme uses only background color, while DarkTheme also carries a
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// prebuilt tiled texture image.
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var (
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// ThemeLight is the shared light theme instance used by the client package.
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ThemeLight = &LightTheme{}
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// ThemeDark is the shared dark theme instance used by the client package.
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ThemeDark = NewDarkTheme()
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)
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// -----------------------------
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// Helpers
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// -----------------------------
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// cRGBA constructs an sRGB color from 8-bit RGBA channels.
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func cRGBA(r, g, b, a uint8) color.Color { return color.RGBA{R: r, G: g, B: b, A: a} }
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// -----------------------------
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// Light Theme (color only)
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// -----------------------------
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// LightTheme is a soft high-contrast theme intended for bright backgrounds.
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type LightTheme struct{}
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func (LightTheme) ID() string { return "theme.light.v1" }
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func (LightTheme) Name() string { return "Light (Soft)" }
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func (LightTheme) BackgroundColor() color.Color { return cRGBA(244, 246, 248, 255) } // #F4F6F8
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func (LightTheme) BackgroundImage() image.Image { return nil }
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func (LightTheme) BackgroundTileMode() BackgroundTileMode { return BackgroundTileNone }
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func (LightTheme) BackgroundScaleMode() BackgroundScaleMode { return BackgroundScaleNone }
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func (LightTheme) BackgroundAnchorMode() BackgroundAnchorMode { return BackgroundAnchorWorld }
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// Base styles per primitive kind (full Style, not override).
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func (LightTheme) PointStyle() Style {
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return Style{
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FillColor: cRGBA(32, 161, 145, 255), // soft teal
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StrokeColor: nil,
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StrokeWidthPx: 0,
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PointRadiusPx: 3.0,
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}
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}
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func (LightTheme) LineStyle() Style {
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return Style{
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FillColor: nil,
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StrokeColor: cRGBA(70, 108, 196, 220), // soft blue
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StrokeWidthPx: 2.0,
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StrokeDashes: nil,
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StrokeDashOffset: 0,
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}
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}
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func (LightTheme) CircleStyle() Style {
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return Style{
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FillColor: cRGBA(133, 110, 201, 60), // soft purple with low alpha
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StrokeColor: cRGBA(133, 110, 201, 200), // soft purple
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StrokeWidthPx: 2.0,
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}
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}
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// Point class overrides.
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func (LightTheme) PointClassOverride(class PointClassID) (StyleOverride, bool) {
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switch class {
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case PointClassDefault:
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return StyleOverride{}, false
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case PointClassTrackUnknown:
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// muted gray-blue
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return StyleOverride{
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FillColor: cRGBA(120, 135, 160, 230),
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PointRadiusPx: new(3.0),
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}, true
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case PointClassTrackIncoming:
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// soft green
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return StyleOverride{
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FillColor: cRGBA(76, 171, 107, 240),
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PointRadiusPx: new(3.5),
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}, true
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case PointClassTrackOutgoing:
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// soft orange
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return StyleOverride{
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FillColor: cRGBA(222, 142, 70, 240),
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PointRadiusPx: new(3.5),
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}, true
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case PointClassUnidentifiedPlanet:
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// soft orange
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return StyleOverride{
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FillColor: cRGBA(192, 192, 192, 255),
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PointRadiusPx: new(2.5),
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}, true
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default:
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return StyleOverride{}, false
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}
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}
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func (LightTheme) LineClassOverride(class LineClassID) (StyleOverride, bool) {
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switch class {
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case LineClassDefault:
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return StyleOverride{}, false
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case LineClassTrackIncoming:
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return StyleOverride{
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StrokeColor: cRGBA(76, 171, 107, 220),
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StrokeWidthPx: new(2.5),
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}, true
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case LineCLassTrackOutgoing:
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return StyleOverride{
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StrokeColor: cRGBA(222, 142, 70, 220),
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StrokeWidthPx: new(2.5),
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}, true
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case LineClassMeasurement:
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// dashed neutral line
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d := []float64{6, 4}
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return StyleOverride{
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StrokeColor: cRGBA(100, 110, 125, 200),
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StrokeWidthPx: new(1.8),
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StrokeDashes: &d,
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StrokeDashOffset: new(0.),
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}, true
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default:
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return StyleOverride{}, false
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}
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}
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func (LightTheme) CircleClassOverride(class CircleClassID) (StyleOverride, bool) {
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switch class {
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case CircleClassDefault:
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return StyleOverride{}, false
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case CircleClassLocalPlanet:
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// blue
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return StyleOverride{
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FillColor: cRGBA(70, 108, 196, 45),
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StrokeColor: cRGBA(70, 108, 196, 220),
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StrokeWidthPx: new(2.2),
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}, true
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case CircleClassOthersPlanet:
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// orange
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return StyleOverride{
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FillColor: cRGBA(222, 142, 70, 50),
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StrokeColor: cRGBA(222, 142, 70, 220),
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StrokeWidthPx: new(2.2),
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}, true
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case CircleClassFreePlanet:
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// green
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return StyleOverride{
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FillColor: cRGBA(76, 171, 107, 45),
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StrokeColor: cRGBA(76, 171, 107, 220),
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StrokeWidthPx: new(2.2),
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}, true
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default:
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return StyleOverride{}, false
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}
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}
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// -----------------------------
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// Dark Theme (color + tiled image)
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// -----------------------------
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// DarkTheme is a dark theme with an optional reusable background tile.
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type DarkTheme struct {
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bg image.Image
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}
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// NewDarkTheme constructs a DarkTheme with its immutable texture tile prepared.
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func NewDarkTheme() *DarkTheme {
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return &DarkTheme{bg: makeDarkBackgroundTile(96, 96)}
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}
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func (*DarkTheme) ID() string { return "theme.dark.v1" }
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func (*DarkTheme) Name() string { return "Dark (Soft + Texture)" }
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func (*DarkTheme) BackgroundColor() color.Color { return cRGBA(30, 32, 38, 255) } // #1E2026
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func (t *DarkTheme) BackgroundImage() image.Image {
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return nil
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// This image is immutable after creation.
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// return t.bg
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}
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func (*DarkTheme) BackgroundTileMode() BackgroundTileMode { return BackgroundTileRepeat }
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func (*DarkTheme) BackgroundScaleMode() BackgroundScaleMode { return BackgroundScaleNone }
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func (*DarkTheme) BackgroundAnchorMode() BackgroundAnchorMode { return BackgroundAnchorViewport }
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// Base styles for dark theme.
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func (*DarkTheme) PointStyle() Style {
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return Style{
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FillColor: cRGBA(120, 214, 198, 255),
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StrokeColor: nil,
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StrokeWidthPx: 0,
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PointRadiusPx: 3.0,
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}
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}
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func (*DarkTheme) LineStyle() Style {
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return Style{
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FillColor: nil,
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StrokeColor: cRGBA(155, 175, 235, 255),
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StrokeWidthPx: 2.0,
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StrokeDashes: nil,
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StrokeDashOffset: 0,
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}
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}
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func (*DarkTheme) CircleStyle() Style {
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return Style{
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FillColor: nil, // cRGBA(186, 160, 255, 255),
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StrokeColor: cRGBA(186, 160, 255, 255),
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StrokeWidthPx: 2.0,
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}
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}
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// Point class overrides.
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func (*DarkTheme) PointClassOverride(class PointClassID) (StyleOverride, bool) {
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switch class {
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case PointClassDefault:
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return StyleOverride{}, false
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case PointClassTrackUnknown:
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return StyleOverride{
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FillColor: cRGBA(150, 160, 175, 255),
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PointRadiusPx: new(3.0),
|
|
}, true
|
|
|
|
case PointClassTrackIncoming:
|
|
return StyleOverride{
|
|
FillColor: cRGBA(132, 219, 162, 255),
|
|
PointRadiusPx: new(3.5),
|
|
}, true
|
|
|
|
case PointClassTrackOutgoing:
|
|
return StyleOverride{
|
|
FillColor: cRGBA(245, 178, 120, 255),
|
|
PointRadiusPx: new(3.5),
|
|
}, true
|
|
|
|
case PointClassUnidentifiedPlanet:
|
|
return StyleOverride{
|
|
FillColor: cRGBA(192, 192, 192, 255),
|
|
PointRadiusPx: new(2.5),
|
|
}, true
|
|
|
|
default:
|
|
return StyleOverride{}, false
|
|
}
|
|
}
|
|
|
|
func (*DarkTheme) LineClassOverride(class LineClassID) (StyleOverride, bool) {
|
|
switch class {
|
|
case LineClassDefault:
|
|
return StyleOverride{}, false
|
|
|
|
case LineClassTrackIncoming:
|
|
return StyleOverride{
|
|
StrokeColor: cRGBA(132, 219, 162, 255),
|
|
StrokeWidthPx: new(2.5),
|
|
}, true
|
|
|
|
case LineCLassTrackOutgoing:
|
|
return StyleOverride{
|
|
StrokeColor: cRGBA(245, 178, 120, 255),
|
|
StrokeWidthPx: new(2.5),
|
|
}, true
|
|
|
|
case LineClassMeasurement:
|
|
d := []float64{6, 4}
|
|
return StyleOverride{
|
|
StrokeColor: cRGBA(170, 175, 190, 255),
|
|
StrokeWidthPx: new(1.8),
|
|
StrokeDashes: &d,
|
|
StrokeDashOffset: new(0.),
|
|
}, true
|
|
|
|
default:
|
|
return StyleOverride{}, false
|
|
}
|
|
}
|
|
|
|
func (*DarkTheme) CircleClassOverride(class CircleClassID) (StyleOverride, bool) {
|
|
switch class {
|
|
case CircleClassDefault:
|
|
return StyleOverride{}, false
|
|
|
|
case CircleClassLocalPlanet:
|
|
return StyleOverride{
|
|
FillColor: cRGBA(155, 175, 235, 255),
|
|
StrokeColor: cRGBA(155, 175, 235, 255),
|
|
StrokeWidthPx: new(2.2),
|
|
}, true
|
|
|
|
case CircleClassOthersPlanet:
|
|
return StyleOverride{
|
|
FillColor: cRGBA(245, 178, 120, 255),
|
|
StrokeColor: cRGBA(245, 178, 120, 255),
|
|
StrokeWidthPx: new(2.2),
|
|
}, true
|
|
|
|
case CircleClassFreePlanet:
|
|
return StyleOverride{
|
|
FillColor: cRGBA(132, 219, 162, 255),
|
|
StrokeColor: cRGBA(132, 219, 162, 255),
|
|
StrokeWidthPx: new(2.2),
|
|
}, true
|
|
|
|
default:
|
|
return StyleOverride{}, false
|
|
}
|
|
}
|
|
|
|
// makeDarkBackgroundTile creates a subtle, low-contrast texture tile.
|
|
// It is intentionally simple: a faint grid + a few diagonal accents.
|
|
// The tile is meant to be repeated.
|
|
func makeDarkBackgroundTile(w, h int) image.Image {
|
|
if w <= 0 || h <= 0 {
|
|
return nil
|
|
}
|
|
img := image.NewRGBA(image.Rect(0, 0, w, h))
|
|
|
|
// Base is transparent; background color is drawn separately.
|
|
// We draw subtle strokes with low alpha.
|
|
grid := color.RGBA{R: 255, G: 255, B: 255, A: 12} // very faint
|
|
diag := color.RGBA{R: 255, G: 255, B: 255, A: 18} // slightly stronger
|
|
dots := color.RGBA{R: 255, G: 255, B: 255, A: 10} // faint dots
|
|
|
|
// Grid spacing (pixels).
|
|
const step = 12
|
|
|
|
// Vertical grid lines.
|
|
for x := 0; x < w; x += step {
|
|
for y := 0; y < h; y++ {
|
|
img.SetRGBA(x, y, grid)
|
|
}
|
|
}
|
|
// Horizontal grid lines.
|
|
for y := 0; y < h; y += step {
|
|
for x := 0; x < w; x++ {
|
|
img.SetRGBA(x, y, grid)
|
|
}
|
|
}
|
|
|
|
// Diagonal accents (sparse).
|
|
for x := 0; x < w; x += step * 2 {
|
|
for i := 0; i < step && x+i < w && i < h; i++ {
|
|
img.SetRGBA(x+i, i, diag)
|
|
}
|
|
}
|
|
|
|
// Small dot pattern.
|
|
for y := step / 2; y < h; y += step {
|
|
for x := step / 2; x < w; x += step {
|
|
img.SetRGBA(x, y, dots)
|
|
}
|
|
}
|
|
|
|
return img
|
|
}
|