Error while capturing resized window?

[Billy2600]

I'm trying to capture the window in order to do a sort of transition effect, but when I capture a resized window it seems to only capture a portion of the screen or display it incorrectly. There are other ways to do the effect I'm looking for, but I'm hoping to get this method working. I am currently developing on Win10 with VS2015. See the following webms:

Default window size: https://webmshare.com/play/Zro60

Resized window: https://webmshare.com/play/jzxXa

This is the code I'm using to capture the window:

txTrans.create( game->window.getSize().x, game->window.getSize().y );
txTrans.update( game->window );
sprTrans.setTexture( txTrans );
 

[Laurent]

Try

sprTrans.setTexture( txTrans, true );

[Billy2600]

Thank you for your reply, but that didn't seem to solve the problem, even after rebuilding.

[dabbertorres]

Do you have any transformations applied to the sprite?

Might just be the video, but it looks to me like there *might* be some scaling going on.

[Billy2600]

Nope. The only things I'm calling from the sprite are setTexture, move, and getGlobalBounds.

[eXpl0it3r]

So does it display okay and just captures wrong?
What capturing software do you use?

[Billy2600]

It displays incorrectly whether being captured by external software or not. By "capture", I meant the built-in function to apply the window's contents to a texture.

[eXpl0it3r]

Can you provide a MCVE?

[Billy2600]

Okay, hopefully this will show you what you need to know. Anything you don't see defined is a member variable or a #define (defines are all caps). Both of these functions run every frame.

void StateGameplay::ScreenTransition( const float dt )
{
        if( !captured )
        {
                // Capture the screen
                txTrans.create( game->window.getSize().x, game->window.getSize().y );
                txTrans.update( game->window );
                sprTrans.setTexture( txTrans, true );
                captured = true;
        }
        else
        {
                sf::Vector2f move;
                switch( lastMove )
                {
                case Directions::N:
                        move = sf::Vector2f( 0, -TRANS_SPEED );
                        break;
                case Directions::E:
                        move = sf::Vector2f( TRANS_SPEED, 0 );
                        break;
                case Directions::S:
                        move = sf::Vector2f( 0, TRANS_SPEED );
                        break;
                case Directions::W:
                        move = sf::Vector2f( -TRANS_SPEED, 0 );
                        break;
                }

                sprTrans.move( move * dt );

                // State gets switched here
}

void StateGameplay::Draw() const
{
        if( transition && captured )
        {
                game->window.draw( sprTrans );
                return; // Don't draw anything else
        }
       
        // etc
}
 

[Rosme]

This is not a MCVE. The concept of a MCVE is that I can take the code and compile it to reproduce the problem. It is minimal and complete. By producing one, it might also show you where the problem reside as you cut more and more of the complexity of your code. At some point, the problem might stop occuring and you can figure out what you cut that actually produces the problem.

[Billy2600]

Sorry for the delay, here's a proper MCVE that's exhibiting the same issue.

#include <SFML/Graphics.hpp>
#include <cstdlib>

#define WIN_WIDTH 640
#define WIN_HEIGHT 480
#define NUM_SHAPES 5
#define MOVE_SPEED 0.05f
#define TRANS_SPEED 0.05f
#define TRANS_DELAY 2000

sf::RenderWindow window( sf::VideoMode( WIN_WIDTH, WIN_HEIGHT ), "SFML Capture MCVE" );
sf::RectangleShape shapes[NUM_SHAPES];
sf::RectangleShape player;
bool transition = false;
bool captured = false;
sf::Int8 lastMove = 0;
sf::Texture txTrans;
sf::Sprite sprTrans;
sf::Clock clkTrans;

void ScreenTransition( const sf::Int8 lastMove ) // 0 = N, 1 = E, 2 = S, 3 = W
{
        if ( !captured )
        {
                // Capture the screen
                txTrans.create( window.getSize().x, window.getSize().y );
                txTrans.update( window );
                sprTrans.setTexture( txTrans, true );
                captured = true;
                clkTrans.restart();
        }
        else
        {
                sf::Vector2f move;
                switch ( lastMove )
                {
                case 0:
                        move = sf::Vector2f( 0, -TRANS_SPEED );
                        break;
                case 1:
                        move = sf::Vector2f( TRANS_SPEED, 0 );
                        break;
                case 2:
                        move = sf::Vector2f( 0, TRANS_SPEED );
                        break;
                case 3:
                        move = sf::Vector2f( -TRANS_SPEED, 0 );
                        break;
                }

                sprTrans.move( move );

                // Fake resetting state
                if ( clkTrans.getElapsedTime().asMilliseconds() > TRANS_DELAY )
                {
                        transition = false;
                        captured = false;
                        player.setPosition( 10, 10 );
                        sprTrans.setPosition( 0, 0 );
                }
        }
}

int main()
{
        for ( int i = 0; i < NUM_SHAPES; i++ )
        {
                shapes[i].setFillColor( sf::Color::Blue );
                shapes[i].setPosition( rand() % WIN_WIDTH, rand() % WIN_HEIGHT );
                shapes[i].setSize( sf::Vector2f( rand() % 1 + 100, rand() % 1 + 100 ) );
        }
        player.setSize( sf::Vector2f( 50, 50 ) );
        player.setPosition( sf::Vector2f( 10, 10 ) );
        player.setFillColor( sf::Color::Red );
        sprTrans.setPosition( sf::Vector2f( 0, 0 ) );

        while ( window.isOpen() )
        {
                sf::Event event;
                while ( window.pollEvent( event ) )
                {
                        if ( event.type == sf::Event::Closed )
                                window.close();
                }

                if ( sf::Keyboard::isKeyPressed( sf::Keyboard::Key::D ) )
                        player.move( MOVE_SPEED, 0 );
                else if ( sf::Keyboard::isKeyPressed( sf::Keyboard::Key::A ) )
                        player.move( -MOVE_SPEED, 0 );
                else if ( sf::Keyboard::isKeyPressed( sf::Keyboard::Key::W ) )
                        player.move( 0, -MOVE_SPEED );
                else if ( sf::Keyboard::isKeyPressed( sf::Keyboard::Key::S ) )
                        player.move( 0, MOVE_SPEED );

                if ( player.getPosition().x < 0 )
                {
                        transition = true;
                        lastMove = 3;
                }
                else if ( player.getPosition().x + 50 > WIN_WIDTH )
                {
                        transition = true;
                        lastMove = 1;
                }
                else if ( player.getPosition().y < 0 )
                {
                        transition = true;
                        lastMove = 0;
                }
                else if ( player.getPosition().y + 50 > WIN_HEIGHT )
                {
                        transition = true;
                        lastMove = 2;
                }

                if ( transition )
                {
                        ScreenTransition( lastMove );
                }

                window.clear();
                if ( transition && captured )
                {
                        window.draw( sprTrans );
                }
                else
                {
                        for ( int i = 0; i < NUM_SHAPES; i++ )
                        {
                                window.draw( shapes[i] );
                        }
                        window.draw( player );
                }
               
                window.display();
        }

        return 0;
}
 

[eXpl0it3r]

So by "resize" you mean, you made the window slightly bigger?
Do you adjust the view?
You'll have to use the same view on the render texture as on the window.

[Billy2600]

Sorry, I thought "resize" would be self-explanatory. I did experiment with the MCVE, but you definitely pointed me toward the solution:

txTrans.create( window.getSize().x, window.getSize().y );
sf::View view;
view = window.getDefaultView();
view.setSize( window.getSize().x, window.getSize().y );
view.setCenter( window.getSize().x / 2, window.getSize().y / 2 );
window.setView( view );
txTrans.update( window );
sprTrans.setTexture( txTrans, true );
 

And then after the transition is done, reset the view (because my intention is to keep the image stretched, not increase the viewport):

window.setView( window.getDefaultView() );
 

I'm sure there's optimizations I can do. Regardless, thank you all for your input.