require 'Qt'

class CannonField < Qt::Widget
    signals 'angleChanged(int)'
    slots 'setAngle(int)'
    
    def initialize(parent = nil)
        super
        @currentAngle = 45
        setPalette( Qt::Palette.new( Qt::Color.new( 250, 250, 200) ) )
	setAutoFillBackground(true)
    end

    def setAngle( degrees )
        if degrees < 5
            degrees = 5
        elsif degrees > 70
            degrees = 70
        end
        if @currentAngle == degrees
            return
        end
        @currentAngle = degrees
        repaint()
        emit angleChanged( @currentAngle )
    end

    def paintEvent( event )
        painter = Qt::Painter.new( self )

        painter.setPen( Qt::NoPen )
        painter.setBrush( Qt::Brush.new(Qt::blue) )

        painter.translate( 0, rect().bottom() )
        painter.drawPie( Qt::Rect.new(-35, -35, 70, 70), 0, 90*16 )
        painter.rotate( - @currentAngle )
        painter.drawRect( Qt::Rect.new(33, -4, 15, 8) )
        painter.end()
    end


    def sizePolicy()
        return Qt::SizePolicy.new( Qt::SizePolicy::Expanding, Qt::SizePolicy::Expanding )
    end
end