device_pixel.cpp¶

Device Pixel Ratio Helper for UI Units Conversion. More...

Namespaces¶

Name
cf
cf::ui
cf::ui::base
cf::ui::base::device

Detailed Description¶

Device Pixel Ratio Helper for UI Units Conversion.

Author: Charliechen114514 (chengh1922@mails.jlu.edu.cn)

Version: 0.1

Date: 2026-02-23

Source code¶

#include "device_pixel.h"

namespace cf::ui::base {
namespace device {

CanvasUnitHelper::CanvasUnitHelper(const qreal devicePixelRatio)
    : devicePixelRatio(devicePixelRatio) {}

qreal CanvasUnitHelper::dpToPx(qreal dp) const {
    // Density-independent pixel to physical pixel
    return dp * devicePixelRatio;
}

qreal CanvasUnitHelper::spToPx(qreal sp) const {
    // Scale-independent pixel to physical pixel (for fonts)
    return sp * devicePixelRatio;
}

qreal CanvasUnitHelper::pxToDp(qreal px) const {
    // Physical pixel to density-independent pixel
    return devicePixelRatio > 0 ? px / devicePixelRatio : px;
}

qreal CanvasUnitHelper::dpi() const {
    // Standard DPI is 96, scale by device pixel ratio
    return 96.0 * devicePixelRatio;
}

CanvasUnitHelper::BreakPoint CanvasUnitHelper::breakPoint(qreal widthDp) {
    if (widthDp < 600.0) {
        return BreakPoint::Compact;
    }
    if (widthDp < 840.0) {
        return BreakPoint::Medium;
    }
    return BreakPoint::Expanded;
}

} // namespace device
} // namespace cf::ui::base

Updated on 2026-03-09 at 10:14:01 +0000