[apps/probability] Create a class law curve view inheriting from curve

view

Change-Id: I3a6aacd3532c4eb9303b9970765e08f546850439

apps/probability/Makefile

@@ -4,6 +4,7 @@ app_objs += $(addprefix apps/probability/,\
   evaluate_context.o\
   law.o\
   law_controller.o\
+  law_curve_view.o\
   parameters_controller.o\
 )
 

apps/probability/law_curve_view.cpp

@@ -0,0 +1,33 @@
+#include "law_curve_view.h"
+#include <assert.h>
+
+namespace Probability {
+
+LawCurveView::LawCurveView(Law * law) :
+  CurveView(),
+  m_law(law)
+{
+}
+
+void LawCurveView::drawRect(KDContext * ctx, KDRect rect) const {
+  ctx->fillRect(bounds(), KDColorWhite);
+  drawAxes(Axis::Horizontal, ctx, rect);
+  drawExpression(m_law->expression(), KDColorRed, ctx, rect);
+}
+
+float LawCurveView::min(Axis axis) const {
+  assert(axis == Axis::Horizontal || axis == Axis::Vertical);
+  return (axis == Axis::Horizontal ? m_law->xMin() : m_law->yMin());
+}
+
+float LawCurveView::max(Axis axis) const {
+  assert(axis == Axis::Horizontal || axis == Axis::Vertical);
+  return (axis == Axis::Horizontal ? m_law->xMax() : m_law->yMax());
+}
+
+float LawCurveView::evaluateExpressionAtAbscissa(Expression * expression, float abscissa) const {
+  m_law->evaluateContext()->setOverridenValueForSymbolT(abscissa);
+  return expression->approximate(*(m_law->evaluateContext()));
+}
+
+}

apps/probability/law_curve_view.h

@@ -0,0 +1,25 @@
+#ifndef PROBABILITY_LAW_CURVE_VIEW_H
+#define PROBABILITY_LAW_CURVE_VIEW_H
+
+#include "../curve_view.h"
+#include "law.h"
+#include <escher.h>
+#include <poincare.h>
+
+namespace Probability {
+
+class LawCurveView : public CurveView {
+public:
+  LawCurveView(Law * law);
+  void drawRect(KDContext * ctx, KDRect rect) const override;
+protected:
+  float min(Axis axis) const override;
+  float max(Axis axis) const override;
+private:
+  float evaluateExpressionAtAbscissa(Expression * expression, float abscissa) const override;
+  Law * m_law;
+};
+
+}
+
+#endif