Files
Upsilon/apps/graph/graph/graph_controller_helper.cpp

37 lines
1.9 KiB
C++

#include "graph_controller_helper.h"
#include "../../shared/function_banner_delegate.h"
#include "../app.h"
#include "../../constant.h"
#include "../../shared/poincare_helpers.h"
using namespace Shared;
using namespace Poincare;
namespace Graph {
bool GraphControllerHelper::privateMoveCursorHorizontally(Shared::CurveViewCursor * cursor, int direction, Shared::InteractiveCurveViewRange * range, int numberOfStepsInGradUnit, Ion::Storage::Record record, App * app) {
ExpiringPointer<CartesianFunction> function = app->functionStore()->modelForRecord(record);
double xCursorPosition = cursor->x();
double x = direction > 0 ? xCursorPosition + range->xGridUnit()/numberOfStepsInGradUnit : xCursorPosition - range->xGridUnit()/numberOfStepsInGradUnit;
double y = function->evaluateAtAbscissa(x, app->localContext());
cursor->moveTo(x, y);
return true;
}
void GraphControllerHelper::reloadDerivativeInBannerViewForCursorOnFunction(Shared::CurveViewCursor * cursor, Ion::Storage::Record record, App * app) {
ExpiringPointer<CartesianFunction> function = app->functionStore()->modelForRecord(record);
constexpr size_t bufferSize = FunctionBannerDelegate::k_maxNumberOfCharacters+PrintFloat::bufferSizeForFloatsWithPrecision(Constant::LargeNumberOfSignificantDigits);
char buffer[bufferSize];
const char * space = " ";
int numberOfChar = function->derivativeNameWithArgument(buffer, bufferSize, CartesianFunction::Symbol());
const char * legend = "=";
numberOfChar += strlcpy(buffer+numberOfChar, legend, bufferSize-numberOfChar);
double y = function->approximateDerivative(cursor->x(), app->localContext());
numberOfChar += PoincareHelpers::ConvertFloatToText<double>(y, buffer + numberOfChar, bufferSize-numberOfChar, Constant::ShortNumberOfSignificantDigits);
strlcpy(buffer+numberOfChar, space, bufferSize-numberOfChar);
bannerView()->derivativeView()->setText(buffer);
bannerView()->reload();
}
}