Topics

1

General / dealing with massive frame time

« on: September 21, 2019, 01:14:07 pm »

When I move/resize window without pausing game, game messes up like Goomba instakills Mario beyond obstacles, because Clock is still progressing while window is completely frozen.
First I fixed it by this:

if(frameTime > 1 / 60.f) frameTime = 1 / 60.f;

But this looks unsmart. This may cause lags when fps drops below 60.
Is there any good way? thx.

2

Graphics / Drawing one time is slower than 100 times.

« on: August 05, 2019, 04:41:03 pm »

Hello, I'm new to SFML and also to C++.
This question is similar to previous one but I also stuck with this problem.

#include <SFML\Graphics.hpp>
#include <iostream>

class Block
{
public:
        Block();
        ~Block();
        void Allocate(sf::Vector2f position, sf::Vector2f size);
        sf::VertexArray GetShape() { return shape; }
        bool CheckAlive() { return alive; }
private:
        sf::VertexArray shape;
        bool alive;
};

Block::Block()
{
}

Block::~Block()
{
}

void Block::Allocate(sf::Vector2f position, sf::Vector2f size)
{
        shape = sf::VertexArray(sf::Quads, 4);
        shape[0].position = position;
        shape[1].position = { position.x + size.x, position.y };
        shape[2].position = { position.x + size.x, position.y + size.y };
        shape[3].position = { position.x, position.y  + size.y};
        shape[0].color = sf::Color::Red;
        shape[1].color = sf::Color::Blue;
        shape[2].color = sf::Color::Green;
        shape[3].color = sf::Color::Yellow;
        alive = true;
}

int main()
{
        sf::RenderWindow window(sf::VideoMode(400, 400), "TEST");
        Block block[100];
        for (int i = 0; i < 10; i++)
                for (int j = 0; j < 10; j++)
                        block[j + 10 * i].Allocate(sf::Vector2f(40.f * j, 40.f * i), sf::Vector2f(40.f, 40.f));
        sf::VertexArray bunchOfShapes(sf::Quads, 0);
        sf::Clock clock;
        float frameTime = 0.f;
        float timer = 0.f;
        int fps = 0;
        while (window.isOpen())
        {
                frameTime = clock.restart().asSeconds();
                sf::Event e;
                while (window.pollEvent(e))
                {
                        if (e.type == sf::Event::Closed)
                                window.close();
                }
                timer += frameTime;
                fps++;
                if (timer >= 1.f)
                {
                        std::cout << fps << std::endl;
                        fps = 0;
                        timer = 0.f;
                }

                window.clear();
                // draw every shapes 100 times.
                for (int i = 0; i < 100; i++)
                        if (block[i].CheckAlive())
                                window.draw(block[i].GetShape());
                // draw one big shape.
                /*for (int i = 0; i < 100; i++)                                                                                
                        if (block[i].CheckAlive())
                                for (int j = 0; j < block[i].GetShape().getVertexCount(); j++)
                                        bunchOfShapes.append(block[i].GetShape()[j]);
                window.draw(bunchOfShapes);*/

                window.display();
        }
}

 

I expected drawing one time is faster but turned to be much worse. Each of those blocks has a state and it is to be changed frequently in game, so this one big shape has to be updated in every frame. This code is definitely wrong but I can't figure out.