[unsolved] Re-sizing and scaling

Newbie & Debugging Questions
#1

I’ve been wondering how to make a games window resizable without just stretching the pixels over a larger screen, or using glOrtho and putting in TOO much content and everything is small.

This is the code I am using, it is called whenever Display.wasResized = true.


	public void resize(){
		glMatrixMode(GL_PROJECTION);
		glLoadIdentity();
		glOrtho(0, Display.getWidth(), Display.getHeight(), 0, 1, -1);
		glMatrixMode(GL_MODELVIEW);

		glEnable(GL_STENCIL_TEST);
		glClearColor(0, 0, 0, 0);
		glEnable(GL_BLEND);
		glBlendFunc(GL_SRC_ALPHA, GL_ONE);
	
		glViewport(0, 0, Display.getWidth(), Display.getHeight());
		glLoadIdentity();
		
		System.out.println("Resized to " + Display.getWidth() + " x " + Display.getHeight());
	}
#2

Depends on what you want.
You can stretch the scenery, cut off the borders, expand the scenery…
What you are doing is the first mentioned way.
Whats your question?

#3

Sorry I wasn’t clear. I meant I want the screen to always be 16:9, and when its resized, scale everything instead of expanding.

#4 

float x, y, width, height;
if(Display.getWidth()/resolution.width < Display.getHeight()/resolution.height)
{
	x = 		0;
	y = 	((Display.getHeight()-((Display.getWidth()/resolution.width)*resolution.height))/2f);
	width = 	Display.getWidth();
	height = 	(Display.getWidth()/resolution.width*resolution.height);
			
}
else
{
	x = 		(int)((Display.getWidth()-((Display.getHeight()/resolution.height)*resolution.width))/2f);
	y = 		0;
	width = 	(int)(Display.getHeight()/resolution.height*resolution.width);
	height = 	Display.getHeight();
}

glViewport((int) x, (int)y, (int)width, (int)height);

Not the best or cleanest way, but a vague idea and it works.

#5

It works, but what I meant is that I wanted the content to always remain in a 16:9 ratio, and when re-sized, kept that way but with a higher resolution.

EDIT: Say I want the player to be here on a 10x5p screen:

*********O

But when I re size it to 11x6, hes here:

********O

#6

This is exactly what this does.
You would have to use the way you were already using, but with these lines instead of the glViewport line.


glMatrixMode(GL_PROJECTION);
glLoadIdentity();
//the code here
glMatrixMode(GL_MODELVIEW);

glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0f, resolution.width, 0f, resolution.height, -1f, 1f);
glMatrixMode(GL_MODELVIEW);
#7

Alright, this is the re-size method now:


	public void resize(){
		glMatrixMode(GL_PROJECTION);
		glLoadIdentity();
		glOrtho(0, Display.getWidth(), Display.getHeight(), 0, 1, -1);
		glMatrixMode(GL_MODELVIEW);

		glEnable(GL_STENCIL_TEST);
		glClearColor(0, 0, 0, 0);
		glEnable(GL_BLEND);
		glBlendFunc(GL_SRC_ALPHA, GL_ONE);

		float x, y;
		if(Display.getWidth() / width < Display.getHeight() / height)
		{
		   x =       0;
		   y =    ((Display.getHeight()-((Display.getWidth() / width) * height))/2f);
		   width =    Display.getWidth();
		   height =    (Display.getWidth()/ width * height);
		         
		}
		else
		{
		   x =       (int)((Display.getWidth()-((Display.getHeight() / height) * width))/2f);
		   y =       0;
		   width =    (int)(Display.getHeight() / height * width);
		   height =    Display.getHeight();
		}

		glViewport((int) x, (int)y, (int)width, (int)height);
		
		System.out.println("Resized to " + Display.getWidth() + " x " + Display.getHeight());
	}

Before I resize it:

After I resize it:

#8

This is what it is supposed to do, yea.
Resize the window and the scene will stay the same.
But you did not use it correctly:

#9

Okay, but what I needed if for it do is to keep the aspect ratio (16:9), and just make the squares, lights and everything bigger and in a higher resolution.

#10

You cannot use Display.getWidth()/Height() for lgOrtho anymore.
This will always resize the scene. Alway use the same values there.

EDIT: You will not necessarily need to use glOrtho more than once at all. Not sure…

#11

I was expecting more along the lines of

glScalef(howMuchX, howMuchY, 0);

to resize the objects with the display.

#12

As mentioned, my method is possibly not the best and for sure not the only one.
But if it is used correctly it does what you expect.

#13

Take a look at the reply to this question. You will obviously have to alter it if you aren’t using LibGDX (and find the code for Scaling.fit.apply()), but I am using this in my game and it works very nicely.

#14

… which is still the same but for libGDX…