constexpr auto kTimelineMarkingsHeight = kTimelineHeight;
constexpr auto kTimelineFontSize = kTimelineHeight * 0.75;
constexpr auto kCompositionHeaderHeight = kTimelineMarkingsHeight + kTimelineHeight;
constexpr auto kAddVoiceItemHeight = kTrackHeight * 0.75;
constexpr auto kAddVoiceArrowHeight = kAddVoiceItemHeight * 0.25;
constexpr auto kMinVoiceItemWidth = kTrackHeight;
constexpr auto kFragmentArrowWidth = kStepWidth / 2;
constexpr auto kFragmentFontSize = kTrackHeight * 0.75;
constexpr auto kVoiceNameFontSize = kTrackHeight * 0.5;
constexpr auto kVoiceNameMargin = (kTrackHeight - kVoiceNameFontSize) / 2;
constexpr auto kCompositionPageSwitchMargin = 50;
constexpr auto kLoopItemOffset = 2.0;
constexpr auto kLoopItemHeight = 8.0;
constexpr auto kCompositionFooterHeight = kLoopItemOffset + kLoopItemHeight;
