Jump to content

  • Log In with Google      Sign In   
  • Create Account


Resize Sprite Texture with Window Resize


Old topic!
Guest, the last post of this topic is over 60 days old and at this point you may not reply in this topic. If you wish to continue this conversation start a new topic.

  • You cannot reply to this topic
6 replies to this topic

#1 Devlin Welson   Members   -  Reputation: 105

Like
0Likes
Like

Posted 28 July 2013 - 07:34 PM

Hello,

 

I wrote a simple basic 2D Game Engine in C++ / Directx 9 but I have a simple problem

Can any one help me find the problem why my sprite texture does not resize with the window when I resize the window the sprite texture size or scale does not change according to the window size

I will post the full source code of my engine and the created game with the sprite so if you can test for me and tell me if you find the problem.

 

The game source is in the Game.cpp file and the Directx Code and Functions is in the frame.cpp file

Try run the game or compile it and resize the window but the sprite texture does not resize

 

By the way I compiled it with Visual Studio 2012

 

Thanks a lot

Attached Files


Edited by Devlin Welson, 28 July 2013 - 07:36 PM.


Sponsor:

#2 Norman Barrows   Crossbones+   -  Reputation: 1850

Like
0Likes
Like

Posted 29 July 2013 - 12:11 PM


Can any one help me find the problem why my sprite texture does not resize with the window when I resize the window the sprite texture size or scale does not change according to the window size

 

directx does not scale sprites to the window size for you. if your window size changes, you must draw at new positions and scales to compensate.

 

getting your sprites to scale automatically with the window size is called "resolution independent graphics".

 

to do resolution independent graphics, you use a virtual coordinate system, such as 10,000x10,000, and make all your draw calls using those. then inside your drawing routines, you convert those to screen coordinates based on the current size of the window:

 

screen_x= (screen_width-1) * virtual_x / 9999         // i think i got that right.... <g>

screen_y= (screen_height-1) * virtual_y / 9999      

 

so you say something like drawsprite(sprite_num,5000,5000,6000,6000) and it always draws the sprite with the upper left corner in the middle of the window, and the size of the sprite is always 1/10 the width and 1/10th the height of the window. 5000 to 6000 is 1000 virtual pixels, and 1000 is 1/10th of 10,000, the virtual width of the window.


Norm Barrows

Rockland Software Productions

"Building PC games since 1988"

 

rocklandsoftware.net

 


#3 Devlin Welson   Members   -  Reputation: 105

Like
0Likes
Like

Posted 29 July 2013 - 08:23 PM

Thanks for the reply, no I think it does resize, I have seen other engines that it resizes with the window. 

Here is another game with the source code and the sprite resizes with the window. I have used some of the code from this game

Attached Files



#4 Endurion   Crossbones+   -  Reputation: 3340

Like
0Likes
Like

Posted 30 July 2013 - 12:39 AM

Well, in your new engine you handle WM_SIZE and resize the back buffer accordingly. Thus the sprite sizes stay the same.

 

In the anti virus game there is no WM_SIZE handler, the back buffer size does not change. In that case Direct3d automatically scales the backbuffer to the window size (and thusly the sprite sizes change).

 

 

Actually the way of the new engine feels cleaner. I have no experience with the sprite system, but you should be able to use a ortho matrix as projection matrix to implement a virtual screen size. Set the ortho width/height to a fixed size irregardless the back buffer size. I'm not sure however if the ID3DXSprites use pretransformed vertices. If they do, you have to use the way Norman Barrows explained.


Fruny: Ftagn! Ia! Ia! std::time_put_byname! Mglui naflftagn std::codecvt eY'ha-nthlei!,char,mbstate_t>

#5 Norman Barrows   Crossbones+   -  Reputation: 1850

Like
0Likes
Like

Posted 30 July 2013 - 05:02 PM

the method i described is for when the back buffer size changes in full screen mode.

 

in windowed mode (which i don't use and am not that familiar with), i believe there's a presentation mode that will do a stretch-blit to the window's client area. this would scale everything automatically, at the cost of a stretch-blit every frame.

 

stretch-blit is one method to get resolution independent graphics in full screen mode, but due to the extra overhead of the stretch-blit every frame, some consider it poor practice.


Norm Barrows

Rockland Software Productions

"Building PC games since 1988"

 

rocklandsoftware.net

 


#6 Devlin Welson   Members   -  Reputation: 105

Like
0Likes
Like

Posted 31 July 2013 - 01:54 AM

I already made my engine to go to full screen mode without losing the directx device and going back to windowed mode this is why I am using WM_SIZE Windows Message to check if the device is lost then reset it. I will read more about it, thanks everyone.

To go fullscreen press F1 and F1 again to back to windows mode


Edited by Devlin Welson, 31 July 2013 - 01:54 AM.


#7 Endurion   Crossbones+   -  Reputation: 3340

Like
1Likes
Like

Posted 31 July 2013 - 04:28 AM

Do not use WM_SIZE to check for a lost device. There are other methods to loose a device (lock the computer, etc.).

 

Simply check the return value of PresentScene (D3DERR_DEVICELOST).

 

http://msdn.microsoft.com/en-us/library/windows/desktop/bb174714(v=vs.85).aspx nicely describes the usual issues.


Fruny: Ftagn! Ia! Ia! std::time_put_byname! Mglui naflftagn std::codecvt eY'ha-nthlei!,char,mbstate_t>




Old topic!
Guest, the last post of this topic is over 60 days old and at this point you may not reply in this topic. If you wish to continue this conversation start a new topic.



PARTNERS