[apps/graph] Faster cursor scrolling on device

This commit is quite dirty but works well

apps/graph/graph/graph_view.cpp

@@ -8,7 +8,7 @@ using namespace Shared;
 namespace Graph {
 
 GraphView::GraphView(CartesianFunctionStore * functionStore, InteractiveCurveViewRange * graphRange,
-  CurveViewCursor * cursor, BannerView * bannerView, View * cursorView) :
+  CurveViewCursor * cursor, BannerView * bannerView, CursorView * cursorView) :
   FunctionGraphView(graphRange, cursor, bannerView, cursorView),
   m_functionStore(functionStore),
   m_tangent(false)

apps/graph/graph/graph_view.h

@@ -9,7 +9,7 @@ namespace Graph {
 class GraphView : public Shared::FunctionGraphView {
 public:
   GraphView(CartesianFunctionStore * functionStore, Shared::InteractiveCurveViewRange * graphRange,
-    Shared::CurveViewCursor * cursor, Shared::BannerView * bannerView, View * cursorView);
+    Shared::CurveViewCursor * cursor, Shared::BannerView * bannerView, Shared::CursorView * cursorView);
   void reload() override;
   void drawRect(KDContext * ctx, KDRect rect) const override;
   void drawTangent(bool tangent) { m_tangent = tangent; }

apps/regression/graph_controller.cpp

@@ -82,9 +82,9 @@ void GraphController::viewWillAppear() {
   /* Since *m_selectedDotIndex is altered by initCursorParameters(),
    * the following must absolutely come at the end. */
   if (*m_selectedDotIndex >= 0) {
-    m_view.setCursorView(static_cast<View *>(&m_crossCursorView));
+    m_view.setCursorView(static_cast<Shared::CursorView *>(&m_crossCursorView));
   } else {
-    m_view.setCursorView(static_cast<View *>(&m_roundCursorView));
+    m_view.setCursorView(static_cast<Shared::CursorView *>(&m_roundCursorView));
     m_roundCursorView.setColor(Palette::DataColor[*m_selectedSeriesIndex]);
   }
 }

apps/regression/graph_view.cpp

@@ -8,7 +8,7 @@ using namespace Shared;
 
 namespace Regression {
 
-GraphView::GraphView(Store * store, CurveViewCursor * cursor, BannerView * bannerView, View * cursorView) :
+GraphView::GraphView(Store * store, CurveViewCursor * cursor, BannerView * bannerView, Shared::CursorView * cursorView) :
   CurveView(store, cursor, bannerView, cursorView),
   m_store(store),
   m_xLabels{},

apps/regression/graph_view.h

@@ -9,7 +9,7 @@ namespace Regression {
 
 class GraphView : public Shared::CurveView {
 public:
-  GraphView(Store * store, Shared::CurveViewCursor * cursor, Shared::BannerView * bannerView, View * cursorView);
+  GraphView(Store * store, Shared::CurveViewCursor * cursor, Shared::BannerView * bannerView, Shared::CursorView * cursorView);
   void drawRect(KDContext * ctx, KDRect rect) const override;
 private:
   char * label(Axis axis, int index) const override;

apps/sequence/graph/graph_view.cpp

@@ -6,7 +6,7 @@ using namespace Shared;
 namespace Sequence {
 
 GraphView::GraphView(SequenceStore * sequenceStore, InteractiveCurveViewRange * graphRange,
-  CurveViewCursor * cursor, BannerView * bannerView, View * cursorView) :
+  CurveViewCursor * cursor, BannerView * bannerView, CursorView * cursorView) :
   FunctionGraphView(graphRange, cursor, bannerView, cursorView),
   m_sequenceStore(sequenceStore)
 {

apps/sequence/graph/graph_view.h

@@ -9,7 +9,7 @@ namespace Sequence {
 class GraphView : public Shared::FunctionGraphView {
 public:
   GraphView(SequenceStore * sequenceStore, Shared::InteractiveCurveViewRange * graphRange,
-    Shared::CurveViewCursor * cursor, Shared::BannerView * bannerView, View * cursorView);
+    Shared::CurveViewCursor * cursor, Shared::BannerView * bannerView, Shared::CursorView * cursorView);
   void drawRect(KDContext * ctx, KDRect rect) const override;
 private:
   SequenceStore * m_sequenceStore;

apps/shared/Makefile

@@ -19,7 +19,6 @@ app_shared_src = $(addprefix apps/shared/,\
   buffer_function_title_cell.cpp \
   buffer_text_view_with_text_field.cpp \
   button_with_separator.cpp \
-  cursor_view.cpp \
   curve_view.cpp \
   curve_view_cursor.cpp \
   editable_cell_table_view_controller.cpp \

apps/shared/cursor_view.cpp

@@ -1,16 +0,0 @@
-#include "cursor_view.h"
-
-namespace Shared {
-
-void CursorView::drawRect(KDContext * ctx, KDRect rect) const {
-  KDCoordinate width = bounds().width();
-  KDCoordinate height = bounds().height();
-  ctx->fillRect(KDRect((width-1)/2, 0, 1, height), KDColorBlack);
-  ctx->fillRect(KDRect(0, (height-1)/2, width, 1), KDColorBlack);
-}
-
-KDSize CursorView::minimalSizeForOptimalDisplay() const {
-  return KDSize(k_size, k_size);
-}
-
-}

apps/shared/cursor_view.h

@@ -5,12 +5,9 @@
 
 namespace Shared {
 
-class CursorView : public TransparentView {
+class CursorView : public View {
 public:
-  void drawRect(KDContext * ctx, KDRect rect) const override;
-  KDSize minimalSizeForOptimalDisplay() const override;
-private:
-  constexpr static KDCoordinate k_size = 19;
+  virtual void setCursorFrame(KDRect frame) { View::setFrame(frame); }
 };
 
 }

apps/shared/curve_view.cpp

@@ -16,7 +16,7 @@ static inline float minFloat(float x, float y) { return x < y ? x : y; }
 static inline float maxFloat(float x, float y) { return x > y ? x : y; }
 
 CurveView::CurveView(CurveViewRange * curveViewRange, CurveViewCursor * curveViewCursor, BannerView * bannerView,
-    View * cursorView, View * okView, bool displayBanner) :
+    CursorView * cursorView, View * okView, bool displayBanner) :
   View(),
   m_bannerView(bannerView),
   m_curveViewCursor(curveViewCursor),
@@ -68,7 +68,7 @@ void CurveView::setCurveViewRange(CurveViewRange * curveViewRange) {
  * might be identical to the previous one and in that case layoutSubviews will
  * do nothing). */
 
-void CurveView::setCursorView(View * cursorView) {
+void CurveView::setCursorView(CursorView * cursorView) {
   markRectAsDirty(cursorFrame());
   m_cursorView = cursorView;
   markRectAsDirty(cursorFrame());
@@ -709,7 +709,7 @@ void CurveView::stampAtLocation(KDContext * ctx, KDRect rect, float pxf, float p
 
 void CurveView::layoutSubviews() {
   if (m_curveViewCursor != nullptr && m_cursorView != nullptr) {
-    m_cursorView->setFrame(cursorFrame());
+    m_cursorView->setCursorFrame(cursorFrame());
   }
   if (m_bannerView != nullptr) {
     m_bannerView->setFrame(bannerFrame());

apps/shared/curve_view.h

@@ -4,6 +4,7 @@
 #include "banner_view.h"
 #include "curve_view_range.h"
 #include "curve_view_cursor.h"
+#include "cursor_view.h"
 #include <poincare/preferences.h>
 #include <poincare/coordinate_2D.h>
 #include <cmath>
@@ -24,15 +25,15 @@ public:
   CurveView(CurveViewRange * curveViewRange = nullptr,
       CurveViewCursor * curveViewCursor = nullptr,
       BannerView * bannerView = nullptr,
-      View * cursorView = nullptr,
+      CursorView * cursorView = nullptr,
       View * okView = nullptr,
       bool displayBanner = true);
   virtual void reload();
   // When the main view is selected, the banner view is visible
   bool isMainViewSelected() const;
   void selectMainView(bool mainViewSelected);
-  View * cursorView() { return m_cursorView; }
-  void setCursorView(View * cursorView);
+  CursorView * cursorView() { return m_cursorView; }
+  void setCursorView(Shared::CursorView * cursorView);
   View * bannerView() { return m_bannerView; }
   void setBannerView(View * bannerView);
   void setOkView(View * okView);
@@ -104,7 +105,7 @@ private:
   float labelValueAtIndex(Axis axis, int i) const;
   bool bannerIsVisible() const;
   CurveViewRange * m_curveViewRange;
-  View * m_cursorView;
+  CursorView * m_cursorView;
   View * m_okView;
   bool m_forceOkDisplay;
   bool m_mainViewSelected;

apps/shared/function_graph_view.cpp

@@ -7,7 +7,7 @@ using namespace Poincare;
 namespace Shared {
 
 FunctionGraphView::FunctionGraphView(InteractiveCurveViewRange * graphRange,
-  CurveViewCursor * cursor, BannerView * bannerView, View * cursorView) :
+  CurveViewCursor * cursor, BannerView * bannerView, CursorView * cursorView) :
   CurveView(graphRange, cursor, bannerView, cursorView),
   m_selectedRecord(),
   m_highlightedStart(NAN),

apps/shared/function_graph_view.h

@@ -12,7 +12,7 @@ namespace Shared {
 class FunctionGraphView : public CurveView {
 public:
   FunctionGraphView(InteractiveCurveViewRange * graphRange, CurveViewCursor * cursor,
-    BannerView * bannerView, View * cursorView);
+    BannerView * bannerView, CursorView * cursorView);
   void drawRect(KDContext * ctx, KDRect rect) const override;
   void setContext(Poincare::Context * context);
   Poincare::Context * context() const;

apps/shared/round_cursor_view.cpp

@@ -2,11 +2,6 @@
 
 namespace Shared {
 
-RoundCursorView::RoundCursorView(KDColor color) :
-  m_color(color)
-{
-}
-
 static constexpr KDCoordinate cursorSize = 10;
 static const uint8_t cursorMask[cursorSize][cursorSize] = {
   {0xFF, 0xFF, 0xFF, 0xED, 0xB6, 0xB6, 0xED, 0xFF, 0xFF, 0xFF},
@@ -24,7 +19,10 @@ static const uint8_t cursorMask[cursorSize][cursorSize] = {
 static KDColor s_cursorWorkingBuffer[cursorSize*cursorSize];
 
 void RoundCursorView::drawRect(KDContext * ctx, KDRect rect) const {
-  ctx->blendRectWithMask(bounds(), m_color, (const uint8_t *)cursorMask, s_cursorWorkingBuffer);
+  KDRect r = bounds();
+  ctx->getPixels(r, m_underneathPixelBuffer);
+  m_underneathPixelBufferLoaded = true;
+  ctx->blendRectWithMask(r, m_color, (const uint8_t *)cursorMask, s_cursorWorkingBuffer);
 }
 
 KDSize RoundCursorView::minimalSizeForOptimalDisplay() const {
@@ -36,4 +34,36 @@ void RoundCursorView::setColor(KDColor color) {
   markRectAsDirty(bounds());
 }
 
+#define GRAPH_CURSOR_SPEEDUP 1
+
+void RoundCursorView::setCursorFrame(KDRect f) {
+#if GRAPH_CURSOR_SPEEDUP
+  /* TODO This is quite dirty (we are out of the dirty tracking and we assume
+   * the cursor is the upmost view) but it works well. */
+  if (m_frame == f) {
+    return;
+  }
+  const KDRect previousRelativeFrame = m_frame;
+  /* We want to avoid drawing the curve just because the cursor has been
+   * repositioned, as it is very slow for non cartesian curves.*/
+  if (m_underneathPixelBufferLoaded && !previousRelativeFrame.isEmpty()) {
+    const KDRect previousFrame = absoluteVisibleFrame();
+    // Erase the cursor
+    KDContext * ctx = KDIonContext::sharedContext();
+    ctx->setOrigin(previousFrame.origin());
+    ctx->setClippingRect(previousFrame);
+    ctx->fillRectWithPixels(KDRect(0,0,k_cursorSize, k_cursorSize), m_underneathPixelBuffer, s_cursorWorkingBuffer);
+    // Set the frame
+    m_frame = f;
+    // Draw the cursor
+    KDPoint translation = f.origin().translatedBy(previousRelativeFrame.origin().opposite());
+    ctx->setOrigin(previousFrame.origin().translatedBy(translation));
+    ctx->setClippingRect(previousFrame.translatedBy(translation));
+    drawRect(ctx, f);
+    return;
+  }
+#endif
+  CursorView::setCursorFrame(f);
+}
+
 }

apps/shared/round_cursor_view.h

@@ -1,18 +1,22 @@
 #ifndef SHARED_ROUND_CURSOR_VIEW_H
 #define SHARED_ROUND_CURSOR_VIEW_H
 
-#include <escher.h>
+#include "cursor_view.h"
 
 namespace Shared {
 
-class RoundCursorView : public TransparentView {
+class RoundCursorView : public CursorView {
 public:
-  RoundCursorView(KDColor color = KDColorBlack);
+  RoundCursorView(KDColor color = KDColorBlack) : m_color(color), m_underneathPixelBufferLoaded(false) {}
   void drawRect(KDContext * ctx, KDRect rect) const override;
   KDSize minimalSizeForOptimalDisplay() const override;
   void setColor(KDColor color);
+  void setCursorFrame(KDRect frame) override;
 private:
+  constexpr static int k_cursorSize = 10;
+  mutable KDColor m_underneathPixelBuffer[k_cursorSize*k_cursorSize];
   KDColor m_color;
+  mutable bool m_underneathPixelBufferLoaded;
 };
 
 }

apps/shared/vertical_cursor_view.h

@@ -2,12 +2,12 @@
 #define SHARED_VERTICAL_CURSOR_VIEW_H
 
 #include <escher.h>
+#include "cursor_view.h"
 
 namespace Shared {
 
-class VerticalCursorView : public View {
+class VerticalCursorView : public CursorView {
 public:
-  using View::View;
   void drawRect(KDContext * ctx, KDRect rect) const override;
   KDSize minimalSizeForOptimalDisplay() const override;
 };

escher/include/escher/view.h

@@ -20,10 +20,15 @@ extern "C" {
 
 class Window;
 
+namespace Shared {
+  class RoundCursorView;
+}
+
 class View {
   // We only want Window to be able to invoke View::redraw
   friend class Window;
   friend class TransparentView;
+  friend class Shared::RoundCursorView;
 public:
   View();
   virtual ~View() {