"Almost equal to" sign in banner views

apps/graph/graph/graph_controller_helper.cpp

@@ -1,6 +1,7 @@
 #include "graph_controller_helper.h"
 #include "../../shared/function_banner_delegate.h"
 #include "../app.h"
+#include <ion/unicode/utf8_decoder.h>
 #include "../../shared/poincare_helpers.h"
 #include <poincare/preferences.h>
 
@@ -34,9 +35,8 @@ void GraphControllerHelper::reloadDerivativeInBannerViewForCursorOnFunction(Shar
   char buffer[bufferSize];
   const char * space = " ";
   int numberOfChar = function->derivativeNameWithArgument(buffer, bufferSize);
-  const char * legend = "=";
   assert(numberOfChar <= bufferSize);
-  numberOfChar += strlcpy(buffer+numberOfChar, legend, bufferSize-numberOfChar);
+  numberOfChar += UTF8Decoder::CodePointToChars(UCodePointAlmostEqualTo, buffer+numberOfChar, bufferSize-numberOfChar);
   double y = function->approximateDerivative(cursor->x(), App::app()->localContext());
   numberOfChar += PoincareHelpers::ConvertFloatToText<double>(y, buffer + numberOfChar, bufferSize-numberOfChar, Preferences::ShortNumberOfSignificantDigits);
   assert(numberOfChar <= bufferSize);

apps/graph/graph/intersection_graph_controller.cpp

@@ -1,7 +1,7 @@
 #include "intersection_graph_controller.h"
+#include <ion/unicode/utf8_decoder.h>
 #include "../../shared/poincare_helpers.h"
 #include <poincare/preferences.h>
-#include <poincare/serialization_helper.h>
 
 using namespace Shared;
 
@@ -22,17 +22,15 @@ void IntersectionGraphController::reloadBannerView() {
   constexpr size_t bufferSize = FunctionBannerDelegate::k_maxNumberOfCharacters+Poincare::PrintFloat::bufferSizeForFloatsWithPrecision(Poincare::Preferences::LargeNumberOfSignificantDigits);
   char buffer[bufferSize];
   const char * space = " ";
-  const char * legend = "=";
-  // 'f(x)=g(x)=', keep 2 chars for '='
+  // 'f(x)=g(x)≈'
   ExpiringPointer<ContinuousFunction> f = functionStore()->modelForRecord(m_record);
-  int numberOfChar = f->nameWithArgument(buffer, bufferSize-2);
+  int numberOfChar = f->nameWithArgument(buffer, bufferSize - UTF8Decoder::CharSizeOfCodePoint('=') - UTF8Decoder::CharSizeOfCodePoint(UCodePointAlmostEqualTo));
   assert(numberOfChar <= bufferSize);
-  numberOfChar += strlcpy(buffer+numberOfChar, legend, bufferSize-numberOfChar);
-  // keep 1 char for '=';
+  numberOfChar += strlcpy(buffer+numberOfChar, "=", bufferSize-numberOfChar);
   ExpiringPointer<ContinuousFunction> g = functionStore()->modelForRecord(m_intersectedRecord);
-  numberOfChar += g->nameWithArgument(buffer+numberOfChar, bufferSize-numberOfChar-1);
+  numberOfChar += g->nameWithArgument(buffer + numberOfChar, bufferSize - numberOfChar - UTF8Decoder::CharSizeOfCodePoint(UCodePointAlmostEqualTo));
   assert(numberOfChar <= bufferSize);
-  numberOfChar += strlcpy(buffer+numberOfChar, legend, bufferSize-numberOfChar);
+  numberOfChar += UTF8Decoder::CodePointToChars(UCodePointAlmostEqualTo, buffer+numberOfChar, bufferSize-numberOfChar);
   numberOfChar += PoincareHelpers::ConvertFloatToText<double>(m_cursor->y(), buffer+numberOfChar, bufferSize-numberOfChar, Poincare::Preferences::MediumNumberOfSignificantDigits);
   assert(numberOfChar <= bufferSize);
   strlcpy(buffer+numberOfChar, space, bufferSize-numberOfChar);

apps/graph/graph/tangent_graph_controller.cpp

@@ -1,6 +1,7 @@
 #include "tangent_graph_controller.h"
 #include "../app.h"
 #include "../../apps_container.h"
+#include <ion/unicode/utf8_decoder.h>
 #include "../../shared/poincare_helpers.h"
 #include <poincare/preferences.h>
 
@@ -72,15 +73,15 @@ void TangentGraphController::reloadBannerView() {
   Poincare::Context * context = textFieldDelegateApp()->localContext();
 
   constexpr int precision = Preferences::MediumNumberOfSignificantDigits;
-  const char * legend = "a=";
-  int legendLength = strlcpy(buffer, legend, bufferSize);
+  int legendLength = strlcpy(buffer, "a", bufferSize);
+  legendLength += UTF8Decoder::CodePointToChars(UCodePointAlmostEqualTo, buffer+legendLength, bufferSize-legendLength);
   ExpiringPointer<ContinuousFunction> function = App::app()->functionStore()->modelForRecord(m_record);
   double y = function->approximateDerivative(m_cursor->x(), context);
   PoincareHelpers::ConvertFloatToText<double>(y, buffer + legendLength, PrintFloat::bufferSizeForFloatsWithPrecision(precision), precision);
   m_bannerView->aView()->setText(buffer);
 
-  legend = "b=";
-  legendLength = strlcpy(buffer, legend, bufferSize);
+  legendLength = strlcpy(buffer, "b", bufferSize);
+  legendLength += UTF8Decoder::CodePointToChars(UCodePointAlmostEqualTo, buffer+legendLength, bufferSize-legendLength);
   Shared::TextFieldDelegateApp * myApp = textFieldDelegateApp();
   assert(function->plotType() == Shared::ContinuousFunction::PlotType::Cartesian);
   y = -y*m_cursor->x()+function->evaluate2DAtParameter(m_cursor->x(), myApp->localContext()).x2();

apps/shared/function_banner_delegate.cpp

@@ -27,7 +27,7 @@ void FunctionBannerDelegate::reloadBannerViewForCursorOnFunction(CurveViewCursor
 
   numberOfChar = function->nameWithArgument(buffer, bufferSize);
   assert(numberOfChar <= bufferSize);
-  numberOfChar += strlcpy(buffer+numberOfChar, "=", bufferSize-numberOfChar);
+  numberOfChar += UTF8Decoder::CodePointToChars(UCodePointAlmostEqualTo, buffer+numberOfChar, bufferSize-numberOfChar);
   numberOfChar += function->printValue(cursor->t(), cursor->x(),cursor->y(), buffer+numberOfChar, bufferSize-numberOfChar, precision, context);
   assert(numberOfChar <= bufferSize);
   strlcpy(buffer+numberOfChar, space, bufferSize-numberOfChar);

ion/include/ion/unicode/code_point.h

@@ -39,6 +39,7 @@ static constexpr CodePoint UCodePointRightwardsArrow          = 0x2192;  // →
 static constexpr CodePoint UCodePointNArySummation            = 0x2211;  // ∑
 static constexpr CodePoint UCodePointSquareRoot               = 0x221a;  // √
 static constexpr CodePoint UCodePointIntegral                 = 0x222b;  // ∫
+static constexpr CodePoint UCodePointAlmostEqualTo            = 0x2248;  // ≈
 static constexpr CodePoint UCodePointMathematicalBoldSmallI   = 0x1d422; // 𝐢
 
 #endif