widget/ScrollbarDrawing.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_widget_ScrollbarDrawing_h
   8 #define mozilla_widget_ScrollbarDrawing_h
   9
  10 #include "mozilla/dom/RustTypes.h"
  11 #include "mozilla/gfx/2D.h"
  12 #include "nsColor.h"
  13 #include "nsITheme.h"
  14 #include "ThemeColors.h"
  15 #include "ThemeDrawing.h"
  16 #include "Units.h"
  17
  18 class nsScrollbarFrame;
  19
  20 namespace mozilla::widget {
  21
  22 class ScrollbarDrawing {
  23  protected:
  24   using DPIRatio = mozilla::CSSToLayoutDeviceScale;
  25   using ElementState = dom::ElementState;
  26   using DocumentState = dom::DocumentState;
  27   using DrawTarget = mozilla::gfx::DrawTarget;
  28   using sRGBColor = mozilla::gfx::sRGBColor;
  29   using Colors = ThemeColors;
  30   using Overlay = nsITheme::Overlay;
  31   using WebRenderBackendData = mozilla::widget::WebRenderBackendData;
  32
  33   enum class Kind : uint8_t {
  34     Android,
  35     Cocoa,
  36     Gtk,
  37     Win10,
  38     Win11,
  39   };
  40
  41   explicit ScrollbarDrawing(Kind aKind) : mKind(aKind) {}
  42
  43  public:
  44   virtual ~ScrollbarDrawing() = default;
  45
  46   enum class ScrollbarKind : uint8_t {
  47     Horizontal,
  48     VerticalLeft,
  49     VerticalRight,
  50   };
  51
  52   DPIRatio GetDPIRatioForScrollbarPart(const nsPresContext*);
  53
  54   static nsScrollbarFrame* GetParentScrollbarFrame(nsIFrame* aFrame);
  55   static bool IsParentScrollbarRolledOver(nsIFrame* aFrame);
  56   static bool IsParentScrollbarHoveredOrActive(nsIFrame* aFrame);
  57
  58   static bool IsScrollbarWidthThin(const ComputedStyle& aStyle);
  59   static bool IsScrollbarWidthThin(nsIFrame* aFrame);
  60
  61   CSSIntCoord GetCSSScrollbarSize(StyleScrollbarWidth, Overlay) const;
  62   LayoutDeviceIntCoord GetScrollbarSize(const nsPresContext*,
  63                                         StyleScrollbarWidth, Overlay);
  64   LayoutDeviceIntCoord GetScrollbarSize(const nsPresContext*, nsIFrame*);
  65
  66   virtual LayoutDeviceIntSize GetMinimumWidgetSize(nsPresContext*,
  67                                                    StyleAppearance aAppearance,
  68                                                    nsIFrame* aFrame) = 0;
  69   virtual Maybe<nsITheme::Transparency> GetScrollbarPartTransparency(
  70       nsIFrame* aFrame, StyleAppearance aAppearance) {
  71     return Nothing();
  72   }
  73
  74   bool IsScrollbarTrackOpaque(nsIFrame*);
  75   virtual sRGBColor ComputeScrollbarTrackColor(nsIFrame*, const ComputedStyle&,
  76                                                const DocumentState&,
  77                                                const Colors&);
  78   virtual sRGBColor ComputeScrollbarThumbColor(nsIFrame*, const ComputedStyle&,
  79                                                const ElementState&,
  80                                                const DocumentState&,
  81                                                const Colors&);
  82
  83   nscolor GetScrollbarButtonColor(nscolor aTrackColor, ElementState);
  84   Maybe<nscolor> GetScrollbarArrowColor(nscolor aButtonColor);
  85
  86   // Returned colors are button, arrow.
  87   virtual std::pair<sRGBColor, sRGBColor> ComputeScrollbarButtonColors(
  88       nsIFrame*, StyleAppearance, const ComputedStyle&, const ElementState&,
  89       const DocumentState&, const Colors&);
  90
  91   virtual bool PaintScrollbarButton(DrawTarget&, StyleAppearance,
  92                                     const LayoutDeviceRect&, ScrollbarKind,
  93                                     nsIFrame*, const ComputedStyle&,
  94                                     const ElementState&, const DocumentState&,
  95                                     const Colors&, const DPIRatio&);
  96
  97   virtual bool PaintScrollbarThumb(DrawTarget&, const LayoutDeviceRect&,
  98                                    ScrollbarKind, nsIFrame*,
  99                                    const ComputedStyle&, const ElementState&,
 100                                    const DocumentState&, const Colors&,
 101                                    const DPIRatio&) = 0;
 102   virtual bool PaintScrollbarThumb(WebRenderBackendData&,
 103                                    const LayoutDeviceRect&, ScrollbarKind,
 104                                    nsIFrame*, const ComputedStyle&,
 105                                    const ElementState&, const DocumentState&,
 106                                    const Colors&, const DPIRatio&) = 0;
 107
 108   template <typename PaintBackendData>
 109   bool DoPaintDefaultScrollbar(PaintBackendData&, const LayoutDeviceRect&,
 110                                ScrollbarKind, nsIFrame*, const ComputedStyle&,
 111                                const ElementState&, const DocumentState&,
 112                                const Colors&, const DPIRatio&);
 113   virtual bool PaintScrollbar(DrawTarget&, const LayoutDeviceRect&,
 114                               ScrollbarKind, nsIFrame*, const ComputedStyle&,
 115                               const ElementState&, const DocumentState&,
 116                               const Colors&, const DPIRatio&);
 117   virtual bool PaintScrollbar(WebRenderBackendData&, const LayoutDeviceRect&,
 118                               ScrollbarKind, nsIFrame*, const ComputedStyle&,
 119                               const ElementState&, const DocumentState&,
 120                               const Colors&, const DPIRatio&);
 121
 122   template <typename PaintBackendData>
 123   bool DoPaintDefaultScrollCorner(PaintBackendData&, const LayoutDeviceRect&,
 124                                   ScrollbarKind, nsIFrame*,
 125                                   const ComputedStyle&, const DocumentState&,
 126                                   const Colors&, const DPIRatio&);
 127   virtual bool PaintScrollCorner(DrawTarget&, const LayoutDeviceRect&,
 128                                  ScrollbarKind, nsIFrame*, const ComputedStyle&,
 129                                  const DocumentState&, const Colors&,
 130                                  const DPIRatio&);
 131   virtual bool PaintScrollCorner(WebRenderBackendData&, const LayoutDeviceRect&,
 132                                  ScrollbarKind, nsIFrame*, const ComputedStyle&,
 133                                  const DocumentState&, const Colors&,
 134                                  const DPIRatio&);
 135
 136   virtual void RecomputeScrollbarParams() = 0;
 137
 138   virtual bool ShouldDrawScrollbarButtons() { return true; }
 139
 140  private:
 141   // The scrollbar sizes for all our scrollbars. Indices are overlay or not,
 142   // then thin or not. Should be configured via ConfigureScrollbarSize.
 143   CSSIntCoord mScrollbarSize[2][2]{};
 144
 145  protected:
 146   // For some kind of style differences a full virtual method is overkill, so we
 147   // store the kind here so we can branch on it if necessary.
 148   Kind mKind;
 149
 150   // Configures the scrollbar sizes based on a single size.
 151   void ConfigureScrollbarSize(CSSIntCoord);
 152
 153   // Configures a particular scrollbar size.
 154   void ConfigureScrollbarSize(StyleScrollbarWidth, Overlay, CSSIntCoord);
 155 };
 156
 157 }  // namespace mozilla::widget
 158
 159 #endif