Comments on: SDL Animation http://www.sdltutorials.com/sdl-animation/ SDL Tutorials - Game Tutorials - Programming Tutorials Tue, 09 Mar 2010 12:44:16 +0000 http://wordpress.org/?v=2.9.1 hourly 1 By: Corolido http://www.sdltutorials.com/sdl-animation/comment-page-7/#comment-6795 Corolido Sun, 21 Feb 2010 21:27:23 +0000 http://devhub.lostfish.org/sdl-animation/#comment-6795 Why to use "Oscillate" when you can just set it to 0 and start over again? I can't notice why would it be useful. Why to use “Oscillate” when you can just set it to 0 and start over again? I can’t notice why would it be useful.

]]> By: Erik http://www.sdltutorials.com/sdl-animation/comment-page-7/#comment-6422 Erik Fri, 05 Feb 2010 04:34:33 +0000 http://devhub.lostfish.org/sdl-animation/#comment-6422 Great tutorial Tim, it's making this very easy! Just wanted to add that the animation sequence for the Yoshi's seem to work better 0->7, 0->7 repeated rather then 0->7->0. Just under If (FrameInc > 0) if (CurrentFrame >= MaxFrames-1) simply just take out the FrameInc=-FrameInc; and put CurrentFrame = 0; hope this is makes sense. Thanks again Tim Awesome tutorial! Great tutorial Tim, it’s making this very easy!
Just wanted to add that the animation sequence for the Yoshi’s seem to work better 0->7, 0->7 repeated rather then 0->7->0.
Just under If (FrameInc > 0) if (CurrentFrame >= MaxFrames-1)
simply just take out the FrameInc=-FrameInc; and put CurrentFrame = 0; hope this is makes sense. Thanks again Tim Awesome tutorial!

]]> By: Tim Jones http://www.sdltutorials.com/sdl-animation/comment-page-7/#comment-6213 Tim Jones Fri, 08 Jan 2010 12:35:38 +0000 http://devhub.lostfish.org/sdl-animation/#comment-6213 Jordan, What sort of problems are you having? All you should have to do is change the framerate with SetFrameRate(). Jordan,
What sort of problems are you having? All you should have to do is change the framerate with SetFrameRate().

]]> By: Jordan http://www.sdltutorials.com/sdl-animation/comment-page-7/#comment-6212 Jordan Fri, 08 Jan 2010 08:07:01 +0000 http://devhub.lostfish.org/sdl-animation/#comment-6212 Hey Tim, was wondering if you could go over how to animate at a different frame rate, e.g, an attack animation. I've been trying to get it work for the past few days, but haven't been able to make any progress. Hey Tim, was wondering if you could go over how to animate at a different frame rate, e.g, an attack animation. I’ve been trying to get it work for the past few days, but haven’t been able to make any progress.

]]> By: Tim Jones http://www.sdltutorials.com/sdl-animation/comment-page-7/#comment-6208 Tim Jones Thu, 07 Jan 2010 18:02:34 +0000 http://devhub.lostfish.org/sdl-animation/#comment-6208 Callum, The problem is that C++ only has one way to inherit another class, so yes, it can seem as if we are saying "CApp is a CEvent." Other languages have fixed this problem by introducing abstract classes, and interfaces. So, keeping this in mind, CApp is really inheriting "characteristics" of an Event listener, in other words, CApp can be an object that can listen. It's not that CApp "is" a CEvent, rather, CApp "behaves" like CEvent. If you want to be a purist with your code, then what you do is a create a CAppListener class (which inherits CEvent), and then create a CAppListener object in your CApp. You can then check the listener in your CApp for events. Update: I want to further clarify by stating that CEvent behaves much more like an interface than anything else, it simply lays out the methods. It does contain one method though with code, which would disqualify it from being a true interface. (Which you could always make a static method somewhere like CEventManager::OnEvent(CEvent* Instance) ). In that sense, the "Class is a SuperClass" would no longer apply. For example, the String class in Java extends "Object", and implements "Serializable", "Comparable", and "CharSequence." Would this apply: "String is a Serializable?" No, but "String behaves like Serializable" or "String can be Serializable" makes sense. Callum,
The problem is that C++ only has one way to inherit another class, so yes, it can seem as if we are saying “CApp is a CEvent.” Other languages have fixed this problem by introducing abstract classes, and interfaces. So, keeping this in mind, CApp is really inheriting “characteristics” of an Event listener, in other words, CApp can be an object that can listen. It’s not that CApp “is” a CEvent, rather, CApp “behaves” like CEvent. If you want to be a purist with your code, then what you do is a create a CAppListener class (which inherits CEvent), and then create a CAppListener object in your CApp. You can then check the listener in your CApp for events.

Update:
I want to further clarify by stating that CEvent behaves much more like an interface than anything else, it simply lays out the methods. It does contain one method though with code, which would disqualify it from being a true interface. (Which you could always make a static method somewhere like CEventManager::OnEvent(CEvent* Instance) ). In that sense, the “Class is a SuperClass” would no longer apply. For example, the String class in Java extends “Object”, and implements “Serializable”, “Comparable”, and “CharSequence.” Would this apply: “String is a Serializable?” No, but “String behaves like Serializable” or “String can be Serializable” makes sense.

]]> By: Callum http://www.sdltutorials.com/sdl-animation/comment-page-7/#comment-6207 Callum Thu, 07 Jan 2010 17:47:48 +0000 http://devhub.lostfish.org/sdl-animation/#comment-6207 Heya Tim, another fantastic tutorial. I was wondering about the basic structure of the program so far...and I can't get my head around why CApp must inherit CEvent? At college we have the words "Inheritance means IS A" tattoo'd into our brains. To me this doesn't seem the case? CApp is a CEvent? If I were to re-write it so CApp has a CEvent member, could I get similar results? My main problem would be with the pure virtual functions...I can't over write them if I dont use inheritance? What do you think? Any feedback would be fab. Thanks again for the tutorials! Heya Tim, another fantastic tutorial.

I was wondering about the basic structure of the program so far…and I can’t get my head around why CApp must inherit CEvent? At college we have the words “Inheritance means IS A” tattoo’d into our brains. To me this doesn’t seem the case? CApp is a CEvent?

If I were to re-write it so CApp has a CEvent member, could I get similar results? My main problem would be with the pure virtual functions…I can’t over write them if I dont use inheritance?

What do you think? Any feedback would be fab.

Thanks again for the tutorials!

]]> By: Tim Jones http://www.sdltutorials.com/sdl-animation/comment-page-6/#comment-6188 Tim Jones Mon, 04 Jan 2010 12:40:16 +0000 http://devhub.lostfish.org/sdl-animation/#comment-6188 Gadd, Thanks, I'll fix that. Andrew & Michael, First, sorry that I missed the question such a long time ago. The primary reason is flexibility - meaning, every entity from the start has the ability to animate independently from everything else. You could do it the way Andrew outlined, and that would be fine. The best alternative would probably be to have a global Animation/Timer object, which you could then pass to all your entities (i.e., Entity->SetAnimationObject() ). This would still leave the flexibility to set the framerate for one particulate entity separately. Gadd,
Thanks, I’ll fix that.

Andrew & Michael,
First, sorry that I missed the question such a long time ago. The primary reason is flexibility – meaning, every entity from the start has the ability to animate independently from everything else. You could do it the way Andrew outlined, and that would be fine. The best alternative would probably be to have a global Animation/Timer object, which you could then pass to all your entities (i.e., Entity->SetAnimationObject() ). This would still leave the flexibility to set the framerate for one particulate entity separately.

]]> By: Michael http://www.sdltutorials.com/sdl-animation/comment-page-6/#comment-6182 Michael Sun, 03 Jan 2010 01:17:47 +0000 http://devhub.lostfish.org/sdl-animation/#comment-6182 As Andrew mentioned above, why did you decide to do the frame rate calculation at the sprite animation level and once in the app's OnRender method? As Andrew mentioned above, why did you decide to do the frame rate calculation at the sprite animation level and once in the app’s OnRender method?

]]> By: Kumar http://www.sdltutorials.com/sdl-animation/comment-page-6/#comment-6082 Kumar Wed, 30 Dec 2009 17:41:02 +0000 http://devhub.lostfish.org/sdl-animation/#comment-6082 Thanks a lot for the tutorial. One of the best SDL tutorial series that i found in the net. Thanks a lot for the tutorial. One of the best SDL tutorial series that i found in the net.

]]> By: Gadd http://www.sdltutorials.com/sdl-animation/comment-page-6/#comment-5684 Gadd Thu, 03 Dec 2009 14:51:01 +0000 http://devhub.lostfish.org/sdl-animation/#comment-5684 Both win32 links are broken btw! (Sorry about the double-post) Both win32 links are broken btw!

(Sorry about the double-post)

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