Files
Upsilon/apps/graph/graph/graph_controller_helper.cpp
2019-09-02 16:55:40 +02:00

49 lines
2.3 KiB
C++

#include "graph_controller_helper.h"
#include "../../shared/function_banner_delegate.h"
#include "../app.h"
#include "../../shared/poincare_helpers.h"
#include <poincare/preferences.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) {
ExpiringPointer<CartesianFunction> function = App::app()->functionStore()->modelForRecord(record);
double tCursorPosition = cursor->t();
double t = tCursorPosition;
double tMin = function->tMin();
double tMax = function->tMax();
double dir = (direction > 0 ? 1.0 : -1.0);
CartesianFunction::PlotType type = function->plotType();
if (type == CartesianFunction::PlotType::Cartesian) {
t+= dir * range->xGridUnit()/numberOfStepsInGradUnit;
} else {
assert(type == CartesianFunction::PlotType::Polar || type == CartesianFunction::PlotType::Parametric);
t += dir * (tMax-tMin)/k_definitionDomainDivisor;
}
Coordinate2D<double> xy = function->evaluateXYAtParameter(t, App::app()->localContext());
cursor->moveTo(t, xy.x1(), xy.x2());
return true;
}
void GraphControllerHelper::reloadDerivativeInBannerViewForCursorOnFunction(Shared::CurveViewCursor * cursor, Ion::Storage::Record record) {
ExpiringPointer<CartesianFunction> function = App::app()->functionStore()->modelForRecord(record);
constexpr size_t bufferSize = FunctionBannerDelegate::k_maxNumberOfCharacters+PrintFloat::bufferSizeForFloatsWithPrecision(Preferences::LargeNumberOfSignificantDigits);
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);
double y = function->approximateDerivative(cursor->x(), App::app()->localContext());
numberOfChar += PoincareHelpers::ConvertFloatToText<double>(y, buffer + numberOfChar, bufferSize-numberOfChar, Preferences::ShortNumberOfSignificantDigits);
assert(numberOfChar <= bufferSize);
strlcpy(buffer+numberOfChar, space, bufferSize-numberOfChar);
bannerView()->derivativeView()->setText(buffer);
bannerView()->reload();
}
}