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[neuro.sys]

Hello, I am trying to use the cube example in the sdk as a base to create a viewer on the PSP. I eventually want to export out models from 3dsmax to the PSP. First, I am trying to get a basic understanding of what is happening in the sample:

I am assuming the cube is constructed with this:

struct Vertex __attribute__((aligned(16))) vertices[12*3] =
{
{0, 0, 0xff7f0000,-1,-1, 1}, // 0
{1, 0, 0xff7f0000,-1, 1, 1}, // 4
{1, 1, 0xff7f0000, 1, 1, 1}, // 5

{0, 0, 0xff7f0000,-1,-1, 1}, // 0
{1, 1, 0xff7f0000, 1, 1, 1}, // 5
{0, 1, 0xff7f0000, 1,-1, 1}, // 1

{0, 0, 0xff7f0000,-1,-1,-1}, // 3
{1, 0, 0xff7f0000, 1,-1,-1}, // 2
{1, 1, 0xff7f0000, 1, 1,-1}, // 6

{0, 0, 0xff7f0000,-1,-1,-1}, // 3
{1, 1, 0xff7f0000, 1, 1,-1}, // 6
{0, 1, 0xff7f0000,-1, 1,-1}, // 7

{0, 0, 0xff007f00, 1,-1,-1}, // 0
{1, 0, 0xff007f00, 1,-1, 1}, // 3
{1, 1, 0xff007f00, 1, 1, 1}, // 7

{0, 0, 0xff007f00, 1,-1,-1}, // 0
{1, 1, 0xff007f00, 1, 1, 1}, // 7
{0, 1, 0xff007f00, 1, 1,-1}, // 4

{0, 0, 0xff007f00,-1,-1,-1}, // 0
{1, 0, 0xff007f00,-1, 1,-1}, // 3
{1, 1, 0xff007f00,-1, 1, 1}, // 7

{0, 0, 0xff007f00,-1,-1,-1}, // 0
{1, 1, 0xff007f00,-1, 1, 1}, // 7
{0, 1, 0xff007f00,-1,-1, 1}, // 4

{0, 0, 0xff00007f,-1, 1,-1}, // 0
{1, 0, 0xff00007f, 1, 1,-1}, // 1
{1, 1, 0xff00007f, 1, 1, 1}, // 2

{0, 0, 0xff00007f,-1, 1,-1}, // 0
{1, 1, 0xff00007f, 1, 1, 1}, // 2
{0, 1, 0xff00007f,-1, 1, 1}, // 3

{0, 0, 0xff00007f,-1,-1,-1}, // 4
{1, 0, 0xff00007f,-1,-1, 1}, // 7
{1, 1, 0xff00007f, 1,-1, 1}, // 6

{0, 0, 0xff00007f,-1,-1,-1}, // 4
{1, 1, 0xff00007f, 1,-1, 1}, // 6
{0, 1, 0xff00007f, 1,-1,-1}, // 5
};

Since there are twelve faces in a cube, and I am guessing that each block of three lines is setting up the 3 verts for each face. My first question is what does each block mean? Are they x,y,x coordinates or some kind of matrix?

Also, I am not sure what the first line is doing, exactly. Is 16 the number of unique verts and 12 the number of faces? Why multiply them?

Thanks for any help!

[holger]

see the "struct Vertex" declaration some lines above the array. The libgu include file could also be helpful to understand the layout.

The array defines 12 triangle faces, each containing 3 vertices.

[Kro]

Just a wild guess, but...
Box has 6 square shaped faces. You have 12 triangles defined (2 for each square)

[neuro.sys]

I am amazind you guys respond so quickly. Thanks! I have a lot of experience with creating 3d content, and am in the process of learning 3d programming. I figure asking questions on an open forum is a good way to learn 3d programming, but if you know of a book especially applicable to this task I, shoot me the ISBN.

[Kro]

If you want to get some basic info on OpenGL programming, take a look at NeHe tutorials.

Assuming you're using Windows, get WinAPI documentation as well (Windows API documentation link at the bottom). Starting with 3D programming on Windows/Linux would make it easier (it's better documented, lots of examples, bigger communities). When you know what and how (very important!) you want to do - go back to homebrew creation. :)

[neuro.sys]

So, I wrote a script in 3DS Max that gives me all the vert info off my own model. I kept the vert number the same to make the test simple. Copied the new vert info over the old in the sample file, compiled and popped onto the PSP and it works. So, my pipeline (even though rough) works. I can get a 12 face model from 3DS Max onto the PSP. So, now the question is, how do I make this general? Can I make an exteral file that has all my vert info on it and read in that data? What are the first steps to lead me to be able to do that?

Thanks!

[ashleydb]

How did you get the new data to copy/paste in the first place? You just use that to write out a text file with that data in it. Just make a .h file and write out the text so it looks just like the cube data in that example, then include that file in your project. Simple.
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[neuro.sys]

My MaxScript spits out data from 3DS Max, then in Dev-C++ I overwrote the original data in the cube.c sample file with my own data. That was just for a test. Now, I want to make the program read in another file so I can eventually have a menu offering choices as to which model to view.


This is the sample cube code that I pasted my own data into:

[ashleydb]

Can't you do fileIO from MaxScript? That would make things more general.
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[neuro.sys]

What I am trying to do is make a general viewer program that runs on the PSP, and anyone can then use my maxscript exporter to create a file. They would then copy the file to their psp and the model viewer would see that new file and load it up. So, I need to understand code that will see files in a psp folder, and then do a read file on the data.

I hope that makes sense...

[Kro]

Play with kernel/fileio sample application. You can use it to read your own file format (if needed). Modify MAX script so it saves it in easier to read format, e.g.:

[ashleydb]

OK. I thought your problem was saving out the file from Max in the first place. PSP FileIO is documented here: http://psp.jim.sh/pspsdk-doc/group__FileIO.html

Searching on the forum brings some interesting discussions too.
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[neuro.sys]

Thanks Kro and Ashley, I will take a look at your suggestions. I really appreciate it. Currently, I can paste in an arbitary numer of polys into the code and get it to display with uvs on the PSP, so this next step will get me even closer to final!

[neuro.sys]

[Tim]

There's a bunch of 3DS loaders floating around the net. In fact, I'm pretty sure I even saw one for QBasic once. A quick google search reveals there's plenty of information on loading the format, though it may not be the ideal format for storing on the psp.

~Tim

[ashleydb]

You are better off saving out indexed vertex arrays into a binary file ready to read into your PSP app. Thats what I've been doing with a Maya plugin I wrote to export models for games.
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[holger]

while you're on it... simply convert on-thy-fly all textures into a PSP native format (power-of-two width, ABGR or BGR component ordering, 5650, 5551, 4444 or 8888 component depth). Then you can pass the loaded textures and vertex data directly to the GE without doing any expensive conversion on the PSP.

[neuro.sys]

Okay, so I am stuck on the file i/o part. All the reference you guys supplied is great, but I need a stupid simple example to really undertand how it works. But, since I was stuck in that part, I want ahead and added button interaction. So, now you can rotate the model with the direction pad, and reset it with the x button.

[cheriff]

first, add in your current code something like this:

[neuro.sys]

Thanks for the feedback Cheriff.

I guess I need a little remedial programming help. Lets say to make things simple, I want to read from an asci file I wrote out of 3DSmax. Do I need to include any special .h files for file IO? I am getting a syntax error here:

[cheriff]

like most systems (that i've ever seen) the FILE struct is defined in <stdio.h>
The screenshot code could be an example for simple file access (it only writes, but man fwrite or fread on a *nix system/online man pages and you'll see they are kinda similar)
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[neuro.sys]

So, that fixed one error, but now I am getting "initializer element is not constant" I googled the problem and got a lot of hits, but none made sense in a file io specific way. Any ideas?

[cheriff]

you dont have that line outside a function (at topmost level) do you? If you need file to be global:

[neuro.sys]

You nailed it. And yes, my c knowledge is lacking, I will admit. I am really a 3D artist who scripts and I am trying to branch out into coding. And, thanks to your help, I can now read in data from a text file! Yea! Next, I have to make a simple menu to allow users to pick a model from a list. Thanks again for the help.

[bumpmann]

i made this prog from the cube sample too, but i have some wrong triangles:


(two are wrong but it's not always the sames)

my msh format has no problem (checked with some tech) , nor texture loading and drawing.

here my code:

[holger]

flush data cache after loading textures and vertices into your arrays, or use uncached pointers to access your arrays.
(can we start some DMA-caching FAQ elaborating somewhere? -- this question becomes quite frequently asked...)

[bumpmann]

can you explain me how to flush this caches or use uncached pointers? i never used caches. (today it is the first time that i'm using the alignement)

[Ratty]

To flush the cache use this

[neuro.sys]

Yeah, the 3ds format is open, but I was referring to a .max file. 3DS is a pretty old format, and has limits on texture names at 8 chars. The exporter I am working on will be more robust that the 3ds format, but you need max to use it...

Also, someone mentioned earlier about using a png or other file format as texture for a model. Right now I just know how to use a raw file. are there any docs on how to load in another texture type?

Thanks again...

Oh, and one last question, bumpman, what psp screen cap software did you use?

[bumpmann]

WAAAAAAAW it work =) thx thx thx to Holger and Ratty !!

i don't understand what is the cache but it work =)


neuro> webcam :D
about the other formats, i think we should search for docs about the format and translate the file to a raw... or use libs as pnglib ?

> about the 3ds format: i won't use this format, because i want put others info into my files ^^. and yes i think it is a bit old now.