In Java, Creating application that supports different resolutions/display modes

Question

I am a beginner who is learning to write games in JAVA.

In the game I am writing, I am trying to get it to support multiple displayModes. First let me tell you a little about how I'm setting the display setting in the first place.

In the beginning of the code, I have an list of display modes I wish to support

//List of supported display modes
private static DisplayMode modes[] = {
    new DisplayMode(640, 480, 32, 0),
    new DisplayMode(1024, 768, 32, 0),
}; 

I then get a list of supported display Modes from the Video Card, comparing the list and use the first matching display mode.

/////////////////////////////////////////////
////Variable Declaration
/////////////////////////////////////////////
private GraphicsDevice vc;

/////////////////////////////////////////////   
//Give Video Card Access to Monitor Screen
/////////////////////////////////////////////
public ScreenManager(){
    GraphicsEnvironment e = GraphicsEnvironment.getLocalGraphicsEnvironment();
    vc = e.getDefaultScreenDevice();
}
/////////////////////////////////////////////
//Find Compatible display mode
/////////////////////////////////////////////
//Compare Display mode supported by the application and display modes supported by the video card
//Use the first matching display mode;
public DisplayMode findFirstCompatibleMode(DisplayMode modes[]){
    DisplayMode goodModes[] = vc.getDisplayModes();
    for(int x=0; x<modes.length; x++){
        for(int y=0; y<goodModes.length; y++){
            if (displayModesMatch(modes[x], goodModes[y])){
                return modes[x];
            }
        }
    }
    return null;
}

/////////////////////////////////////////////   
//Checks if two Display Modes match each other
/////////////////////////////////////////////
public boolean displayModesMatch(DisplayMode m1, DisplayMode m2){

    //Test Resolution
    if (m1.getWidth() != m2.getWidth() || m1.getHeight() != m2.getHeight()){
        return false;
    }

    //Test BitDepth
    if (m1.getBitDepth() != DisplayMode.BIT_DEPTH_MULTI && m2.getBitDepth() != DisplayMode.BIT_DEPTH_MULTI
            && m1.getBitDepth() != m2.getBitDepth()){
        return false;
    }

    //Test Refresh Rate
    if (m1.getRefreshRate() != DisplayMode.REFRESH_RATE_UNKNOWN &&
            m2.getRefreshRate() != DisplayMode.REFRESH_RATE_UNKNOWN &&
            m1.getRefreshRate() != m2.getRefreshRate()){
        return false;
    }

    return true;
}

Currently, I am only supporting two resolutions, 640x480 and 1024x768.

In order to have every element of my game available in both resolutions, first I find how much the screen is resized and store this value in a variable called resizeRatio

private void getResizeRatio(){
    resizeRatio = (double)1024/(double)s.getWidth();
    //s.getWidth() returns the current width of the screen.
}

And with every image I import, i would divide the image height and width by this resizeRatio.

/////////////////////////////////////////////
//Scale the image to the right proportion for the resolution
/////////////////////////////////////////////
protected Image scaleImage(Image in){
    Image out = in.getScaledInstance((int)(in.getWidth(null)/resizeRatio), (int)(in.getHeight(null)/resizeRatio), Image.SCALE_SMOOTH);
    return out;
}

This is all fine and good, until my application grew bigger and bigger. Soon I realize I forgot to resize some of the icons, and they are all at the wrong place when resolution is 640x480.

Additionally, I realize I must scale, not just the size of all my images, but all the movement speed, and all the positions as well, since having my character move at 5px per refresh makes him move significantly faster when displayed at 640x480 than when displayed at 1024x768

So my question is, instead of individually scaling every image, every icon, and every movement, is there a way to scale everything all at once? Or rather, there must be another way of doing this so could someone please tell me?

Thank you for reading and any help would be much appreciated.

Answer 1

In the paintComponent(Graphics g) or paint method you can do with Graphics2D.scale:

private double scale = 0.75;

@override
public void paintComponent(Graphics g) {
    Graphics2D g2 = (Graphics2D)g; // The newer more ellaborate child class.
    g2.scale(scale, scale);
    ...
    g2.scale(1/scale, 1/scale);
}