I'm working on a small paint like program which for now only can make circles. I am working on a feature, which show what the circle will look like before it's placed. You can move the mouse to shrink or expand the circle preview if you haven't released the right mouse button. It seems to be working, but I have 2 problems:
1. The shape is not dynamicly updating when moving the mouse
2.I need to find a way to calculate the radius of the circle depending on how many pixels the mouse has moved. Is the size measured in pixels?
main.cpp
#include <SFML/Graphics.hpp>
#include <SFML/Window.hpp>
#include <SFML/System.hpp>
#include "Shapes.h"
#include <iostream>
#include <string>
#include <vector>
#include <cstdlib>
constexpr float pi = 3.14;
sf::CircleShape sizeSelection(sf::Vector2f mousePosition, int shapeSize)
{
sf::CircleShape circle;
circle.setFillColor(sf::Color(136, 167, 216));
circle.setPosition(mousePosition);
circle.setRadius(shapeSize);
return circle;
}
int main()
{
std::string versionString = "1.2.2";
std::string title = "Little Painter " + versionString;
//window related stuff
sf::VideoMode screenSize = sf::VideoMode::getDesktopMode();
sf::RenderWindow window(sf::VideoMode(screenSize.width / 2, screenSize.height / 2), title);
sf::View defaultView(sf::FloatRect(0.f, 0.f, screenSize.width, screenSize.height));
window.setView(defaultView);
window.setFramerateLimit(60);
sf::Event event;
//gui elements
sf::RectangleShape brushTypeGUI(sf::Vector2f(200, 30)), dotColorGUI(sf::Vector2f(200, 30)), canvas(sf::Vector2f(1020, 800)), clearCanvasGUI(sf::Vector2f(200, 30)), changeBrushGUI(sf::Vector2f(200, 30));
//gui setters
brushTypeGUI.setPosition(0, 0);
dotColorGUI.setPosition(202, 0);
clearCanvasGUI.setPosition(404, 0);
canvas.setPosition(120 ,112);
//text elements
sf::Text brushTypeText, dotColorText, clearCanvasText;
sf::Font font;
//text setters
brushTypeText.setString("Change Brush");
brushTypeText.setCharacterSize(24);
brushTypeText.setFillColor(sf::Color::White);
brushTypeText.setFont(font);
brushTypeText.setPosition(25, 0);
dotColorText.setString("Dot Color");
dotColorText.setCharacterSize(24);
dotColorText.setFillColor(sf::Color::White);
dotColorText.setFont(font);
dotColorText.setPosition(252, 1);
clearCanvasText.setString("Clear Canvas");
clearCanvasText.setCharacterSize(24);
clearCanvasText.setFillColor(sf::Color::White);
clearCanvasText.setFont(font);
clearCanvasText.setPosition(433, 1);
font.loadFromFile("expressway rg.ttf");
//time
sf::Time sleepTime = sf::milliseconds(10);
//ranodom stuff
std::vector<sf::CircleShape> circles;
std::vector<sf::RectangleShape> rectangles;
sf::VertexArray lines(sf::LinesStrip, 4);
int defaultSize = 15, r = 0, g = 100, b = 0;
bool selectingSize = false;
sf::Vector2i oldPosition = sf::Mouse::getPosition(window);
Shapes brush;
brush.setBrushType("circle");
while(window.isOpen() == true)
{
while(window.pollEvent(event))
{
//gui setters
brushTypeGUI.setFillColor(sf::Color(33, 33, 33));
dotColorGUI.setFillColor(sf::Color(33, 33, 33));
clearCanvasGUI.setFillColor(sf::Color(33, 33, 33));
//mouse position
sf::Vector2i mousePosition = sf::Mouse::getPosition(window);
sf::Vector2f mouseCoords = window.mapPixelToCoords(mousePosition);
//setting bounds of gui elements
sf::FloatRect dotColorGUIBounds = dotColorGUI.getGlobalBounds();
sf::FloatRect clearCanvasGUIBounds = clearCanvasGUI.getGlobalBounds();
sf::FloatRect canvasBounds = canvas.getGlobalBounds();
int r;
if(event.type == sf::Event::Closed)
{
window.close();
}
if(event.type == sf::Event::Resized)
{
window.setView(defaultView);
}
if(event.type == sf::Event::MouseButtonPressed)
{
if(canvasBounds.contains(mouseCoords))
{
//if reset the position of lastPosition
if(oldPosition == sf::Vector2i(0, 0))
{
oldPosition = mousePosition;
}
//check if mouse has moved since the begging of the size selection
if(oldPosition != mousePosition)
{
//try to calculate the radius of a
r = ((oldPosition.x - mousePosition.x) - (oldPosition.y - mousePosition.y)) / 2;
std::cout<<r<<" "<<mousePosition.x<<" "<<mousePosition.y<<std::endl;
circles.pop_back();
//set the oldPosition to current mousePosition
oldPosition = mousePosition;
circles.push_back(sizeSelection(mouseCoords, r));
}
//if mouse hasn't moved set the size to the defaultSize
else
{
circles.push_back(sizeSelection(mouseCoords, defaultSize));
}
selectingSize = true;
}
}
if(event.type == sf::Event::MouseButtonReleased && selectingSize == true)
{
if(event.mouseButton.button == sf::Mouse::Right)
{
if(canvasBounds.contains(mouseCoords))
{
//remove the size Selection circle
circles.pop_back();
//set oldPosition to 0, 0 so it can be reset
oldPosition = (sf::Vector2i(0, 0));
//go out of selectingSize
selectingSize = false;
brush.setData(mouseCoords, defaultSize, r, g, b);
switch(brush.getBrushType())
{
case Shapes::Circle:
circles.push_back(brush.drawCircle());
break;
case Shapes::Rectangle:
rectangles.push_back(brush.drawRectangle());
break;
}
}
}
}
if(dotColorGUIBounds.contains(mouseCoords))
{
dotColorGUI.setFillColor(sf::Color(40, 50, 95));
if(event.type == sf::Event::MouseButtonPressed)
{
if(event.mouseButton.button == sf::Mouse::Left)
{
r = rand() % 255;
g = rand() % 255;
b = rand() % 255;
}
}
}
if(clearCanvasGUIBounds.contains(mouseCoords))
{
clearCanvasGUI.setFillColor(sf::Color(40, 50, 95));
if(event.type == sf::Event::MouseButtonPressed && event.key.code == sf::Mouse::Left)
{
circles.clear();
}
}
if(event.type == sf::Event::MouseWheelMoved)
{
defaultSize += (event.mouseWheel.delta + 0.8);
}
}
window.clear(sf::Color(61,61,61));
window.draw(brushTypeGUI);
window.draw(brushTypeText);
window.draw(dotColorGUI);
window.draw(dotColorText);
window.draw(clearCanvasGUI);
window.draw(clearCanvasText);
window.draw(canvas);
for(const auto it : circles)
{
window.draw(it);
}
window.draw(lines);
window.display();
}
}
Ah, I didn't realize that OP wanted the circle updated in real time. In that case just calculate position at every frame with the mouse moved event. Here's an example:
#include <SFML/Graphics.hpp>
int main()
{
sf::RenderWindow WINDOW(sf::VideoMode(800, 450), "SFML works!");
WINDOW.setFramerateLimit(60);
bool Dragging = false;
sf::Vector2f MousePosition;
sf::Vector2f OldPosition;
float Radius = 50;
sf::CircleShape Circle{ Radius };
while (WINDOW.isOpen())
{
MousePosition = static_cast<sf::Vector2f>(sf::Mouse::getPosition(WINDOW));
// -- EVENTS
sf::Event EVENT;
while (WINDOW.pollEvent(EVENT))
{
switch (EVENT.type)
{
case sf::Event::Closed: WINDOW.close(); break;
case sf::Event::MouseButtonPressed:
if (EVENT.mouseButton.button == sf::Mouse::Left)
{
Dragging = true;
OldPosition = MousePosition;
}
case sf::Event::MouseMoved:
if (Dragging)
{
sf::Vector2f Delta = OldPosition - MousePosition;
Radius = Radius + Delta.x;
OldPosition = MousePosition;
}
break;
case sf::Event::MouseButtonReleased:
if (EVENT.mouseButton.button == sf::Mouse::Button::Left) { Dragging = false; }
break;
}
}
Circle.setRadius(Radius);
WINDOW.clear();
WINDOW.draw(Circle);
WINDOW.display();
}
return 0;
}