Rachel's Dev-Blog

Do you mind if I call you Mumbly-chan? Okay Mumbly-chan, here's my suggestion: Lower the scope of your project. Let's just get something done, no matter how humble.

 

I won't actually be able to incorporate RPG gameplay until Leadwerks 3 so for now the scope of my project is less than it was before. Now my goal is just to have a character run around and interact with the environment and to basically collision test whack a monster into oblivion. No inventory, no save system, no cut scenes. All extremely simple stuff.

 

Because that's what I'm capable of right now even when I try my best!

I'm no math genius, but i was able to google you an example code

 

http://www.euclideanspace.com/maths/algebra/matrix/functions/inverse/fourD/index.htm

 

You will need the picture in the upper right corner here, to rename the variables in the right way.

 

Will take some time renaming all the variables

The 16 members of a 4x4 matrix are usually numbered in mathematics like Y and X coordinate (the university teachers speak of columns and rows, which is kinda stupid, since even I think in Excel with x and y coordinates (much easier to make VB scripts that way)).

 

So when they say m11,m12,m13,m14 (or m00,m01,m02,m03, if they start with 0 instead of 1, which is unusual since when talking about columns and rows you start with 1, so basically mathematicians have no clue about consistency, only C++ programmers do), they actually mean: cell at coordinate 1,1; 2,1; 3,1; 4,1. So in LE you have TVec16 which calls them A0,A1,A2,A3. For y==2, it's called B0,B1,B2,B3, etc...

 

I could have called them like in mathematics, but then I would have needed to use y,x=x,y coordinate system, which would cause even more confusion between programmers and mathematicians. So calling them with letter+index can not be interpreted wrong, and it's also shorter to type. And yes, it is a common standard notation also, I checked several sites about it. It also unifies vector and matrix notation which is kinda cool.

 

And since it's a Vec16, and not a Mat4 (which are the same thing though), you don't use x and y coordinates in Vecs. If I would have used Mat4, it would have been inconsistent again since it would be totally different that the Vec2,3,4,6 structs, which I wanted to avoid, since it's basically the same thing: just a container for an n-amount of floats.

 

However, in addition to TVec16, there could be also TMat4 in the C headers, which would be the same as TVec16, but only using different member names. How useful that would be, I don't know.

I didn't have any issues with the A0 through D3 element numbering, I figured that bit out. My point was that a Vec16 didn't have an invert operation. At the time, I thought this was some proprietary code of Josh's that just didn't exist anywhere else.

 

 

...But it looks like DaDonik has solved that bit for me. The code on the highlighted site doesn't look very complicated... just long. I can live with long, so long as I know what it's trying to do.

 

What I don't know about that code is why it works... But that's not important in maths. Maths isn't about explanations, it's about blindly following rules. Things only go wrong when you don't follow the rules correctly, or follow the wrong rules.

 

In any case, when I get a bit of motivation back, I will try it out and hopefully carry on with the project.

Two things from a german -

 

one does not need to know everything but one need to know where to find the right answer.

 

Dont downgrade your reality or youll end up somewhere completely different as initially planned.

 

PS: Vector and matrix math seams to be the only game programming related math i continuously find in the interwebs.

After a bit of reading, I can now invert a 3x3 matrix. Apparently inverting a 4x4 is jst a matter of breaking it down into four 3x3s? Or something like that...

 

Maths just seems to be one of those things that if you don't learn in school/college, it becomes so much harder to learn it yourself later. If i'd learned it at college, it would probably be really easy for me to do...

Don't worry, I've learned everything in university, but never understood linear algebra which talked about m*n matrices and their operations.

That's why you buy a entity oriented game engine like LE, so you don't have to use maths ever in your life again.

All you need is PositionEntity, TurnEntity, PointEntity, and other of those simple, logical and natural commands.

Its too early in the morning to understand what you guys talking about but it does look interessting. I'll have another look in the afternoon.

 

I do agree with pancakes on the complexity. Although you are smart enough to find it out eventually, you can save yourself a lot of time by doing things a little more simplified.

 

Good luck with your progress!

All you need is PositionEntity, TurnEntity, PointEntity, and other of those simple, logical and natural commands.

 

That works... until the commands require a graphics context.

 

I'm not ready to do dedicated servers yet. But when I am, I don't want to have make loads of changes. I think it's better to try and get it right first time.