Method Clear

src/SFGUI/Canvas.cpp:352–392

}

void Canvas::Clear( const sf::Color& color, bool depth ) {
	auto allocation = GetAllocation();

	if( !m_render_texture ) {
		// Make sure there is a non-internal/shared context active.
		// After 8 hours of debugging, I found out that if you deactivate the
		// currently active context and construct a sf::RenderTexture, it leads
		// to the sf::RenderTexture's internal OpenGL texture being created
		// in a "corrupted" context leading to OpenGL possibly generating the
		// same texture IDs that it already previously generated and are still in
		// use. Since 2 textures share the same ID, when you draw to the
		// sf::RenderTexture it actually overwrites whatever was in the other
		// normally created texture. This leads to very exotic looking sf::Sprites,
		// not for the end-user. SFML context management strikes again.
		sf::Context context;

		m_render_texture = std::make_shared<sf::RenderTexture>();

		if( !m_render_texture->resize( { static_cast<unsigned int>( std::floor( allocation.size.x + .5f ) ), static_cast<unsigned int>( std::floor( allocation.size.y + .5f ) ) }, sf::ContextSettings{ m_depth } ) ) {
#if defined( SFGUI_DEBUG )
			std::cerr << "SFGUI warning: Canvas failed to create internal SFML RenderTexture.\n";
#endif
		}
	}
	else if( m_resize ) {
		if( !m_render_texture->resize( { static_cast<unsigned int>( std::floor( allocation.size.x + .5f ) ), static_cast<unsigned int>( std::floor( allocation.size.y + .5f ) ) }, sf::ContextSettings{ m_depth } ) ) {
#if defined( SFGUI_DEBUG )
			std::cerr << "SFGUI warning: Canvas failed to create internal SFML RenderTexture.\n";
#endif
		}
	}

	m_resize = false;

	(void)m_render_texture->setActive( true );

	WipeStateCache( *m_render_texture );

	CheckGLError( glClearColor( color.r / 255.f, color.g / 255.f, color.b / 255.f, color.a / 255.f ) );
	CheckGLError( glClear( GL_COLOR_BUFFER_BIT | ( depth ? GL_DEPTH_BUFFER_BIT : 0 ) ) );
}

void Canvas::Display() const {
	if( !m_render_texture ) {