65 lines
1.9 KiB
C++
65 lines
1.9 KiB
C++
|
#include "VectorField.hpp"
|
||
|
|
|
||
|
|
#include <SDL.h>
|
||
|
|
|
||
|
|
VectorField::VectorField() :
|
||
|
|
width(0), height(0), biggestMagnitude(1.0)
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
VectorField::VectorField(int width, int height) :
|
||
|
|
width(width), height(height)
|
||
|
|
{
|
||
|
|
horizontal = std::vector<double>(width * height, 0.0);
|
||
|
|
vertical = std::vector<double>(width * height, 0.0);
|
||
|
|
|
||
|
|
biggestMagnitude = 1.0f;
|
||
|
|
}
|
||
|
|
|
||
|
|
VectorField::VectorField(int width, int height, const std::vector<double>& hori, const std::vector<double>& vert) :
|
||
|
|
width(width), height(height)
|
||
|
|
{
|
||
|
|
horizontal = hori;
|
||
|
|
vertical = vert;
|
||
|
|
|
||
|
|
for (double u : horizontal)
|
||
|
|
{
|
||
|
|
for (double v : vertical)
|
||
|
|
{
|
||
|
|
biggestMagnitude = std::max(biggestMagnitude, u * u + v * v);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if (biggestMagnitude == 0.0) // should use an epsilon probably
|
||
|
|
biggestMagnitude = 1.0;
|
||
|
|
|
||
|
|
biggestMagnitude = sqrt(biggestMagnitude);
|
||
|
|
}
|
||
|
|
|
||
|
|
void VectorField::Draw(SDL_Renderer* renderer, const SDL_Rect& targetRect)
|
||
|
|
{
|
||
|
|
double cellWidth = (double)(targetRect.w - targetRect.x) / (double)width;
|
||
|
|
double cellHeight = (double)(targetRect.h - targetRect.y) / (double)height;
|
||
|
|
|
||
|
|
SDL_FRect vectorCenterSquare;
|
||
|
|
vectorCenterSquare.w = cellWidth / 5.0;
|
||
|
|
vectorCenterSquare.h = cellHeight / 5.0;
|
||
|
|
|
||
|
|
SDL_SetRenderDrawColor(renderer, 200, 20, 20, 255);
|
||
|
|
for (int y = 0; y < height; y++)
|
||
|
|
{
|
||
|
|
for (int x = 0; x < width; x++)
|
||
|
|
{
|
||
|
|
vectorCenterSquare.x = (double)targetRect.x + cellWidth * (x + 0.4); // cellWidth * x + cellWidth / 2 - cellWidth / 10
|
||
|
|
vectorCenterSquare.y = (double)targetRect.y + cellHeight * (y + 0.4);
|
||
|
|
SDL_RenderFillRectF(renderer, &vectorCenterSquare);
|
||
|
|
SDL_RenderDrawLineF(renderer,
|
||
|
|
(double)targetRect.x + cellWidth * (x + 0.5),
|
||
|
|
(double)targetRect.y + cellHeight * (y + 0.5),
|
||
|
|
(double)targetRect.x + cellWidth * (x + 0.5) + horizontal[y * width + x] / biggestMagnitude * cellWidth,
|
||
|
|
(double)targetRect.y + cellHeight * (y + 0.5) + vertical[y * width + x] / biggestMagnitude * cellHeight
|
||
|
|
);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|