GuiTheme.cpp

/****************************************************************************
 * libgui
 * Daryl Borth 2026
 * GuiTheme.cpp
 *
 * No colors or numbers that make up a look live here: they come from the
 * application's GuiThemeInit().
 ***************************************************************************/
 
#include <cstring>
#include "GuiTheme.h"
 
static PixelColor withAlpha(PixelColor c, uint8_t a)
{
    c.a = a;
    return c;
}
 
// the ends the lighten/darken mixes run toward
static const PixelColor WHITE = { 255, 255, 255, 255 };
static const PixelColor BLACK = { 0, 0, 0, 255 };
 
GuiTheme::GuiTheme()
{
    memset(this, 0, sizeof(*this));
}
 
static GuiTheme& makeCurrent()
{
    static GuiTheme theme;
    GuiThemeInit(theme);
    return theme;
}
 
GuiTheme& GuiTheme::current()
{
    static GuiTheme& theme = makeCurrent();
    return theme;
}
 
GuiShapeStyle GuiTheme::panelStyle() const
{
    return GuiShapeStyle(GuiPaint().color(surface).stroke(strokeWidth, outline));
}
 
GuiShapeStyle GuiTheme::cardStyle() const
{
    GuiPaint rest = GuiPaint()
        .gradient(surfaceRaised, surface)
        .stroke(strokeWidth, outline)
        .shadow(shadowBlur, shadow, 0.0f, shadowOffsetY);
    GuiPaint lit = GuiPaint()
        .gradient(surfaceRaised, surface)
        .stroke(strokeWidth, accent)
        .glow(shadowBlur + glowGrow, withAlpha(accent, focusGlowAlpha), glowGrow);
    GuiPaint pressed = GuiPaint()
        .gradient(surface, surfaceRaised)
        .stroke(strokeWidth, accent)
        .glow(shadowBlur, withAlpha(accent, pressGlowAlpha));
    GuiPaint off = GuiPaint()
        .color(withAlpha(surface, cardDisabledAlpha))
        .stroke(strokeWidth, withAlpha(outline, cardDisabledAlpha));
    return GuiShapeStyle(rest).onFocus(lit).onPress(pressed).onDisable(off);
}
 
GuiShapeStyle GuiTheme::buttonStyle() const
{
    const PixelColor litStroke = GuiMixColor(accentLight, WHITE, buttonStrokeLight);
    GuiPaint rest = GuiPaint()
        .gradient(outlineStrong, outline)
        .stroke(strokeWidth, outlineStrong);
    GuiPaint lit = GuiPaint()
        .gradient(accentLight, accent)
        .stroke(strokeWidth, litStroke)
        .glow(buttonGlowBlur, withAlpha(accent, buttonGlowAlpha));
    GuiPaint pressed = GuiPaint()
        .gradient(accent, accentDark)
        .stroke(strokeWidth, litStroke);
    GuiPaint off = GuiPaint()
        .color(withAlpha(surface, buttonDisabledAlpha))
        .stroke(strokeWidth, withAlpha(outline, buttonDisabledAlpha));
    return GuiShapeStyle(rest).onFocus(lit).onPress(pressed).onDisable(off);
}
 
GuiShapeStyle GuiTheme::chipStyle() const
{
    return GuiShapeStyle(GuiPaint().color(outline));
}
 
GuiShapeStyle GuiTheme::rowStyle() const
{
    GuiPaint lit = GuiPaint().color(highlight);
    GuiPaint pressed = GuiPaint().color(withAlpha(accent, rowPressAlpha));
    return GuiShapeStyle(GuiPaint()).onFocus(lit).onPress(pressed);
}
 
GuiShapeStyle GuiTheme::barStyle() const
{
    return GuiShapeStyle(GuiPaint().color(GuiMixColor(background, BLACK, barDarken)));
}