4kb Rotating Cube Demo

[mankrip]

My two cents:

Raw data isn't knowledge. Reverse engineering tells us what happens, but not why it was made to happen. It's up to us to connect the results so we can deduce the reasons why the creators of the system wanted it to be the way it is. Nobody is going to tell us that.

So, when one is reversing engineering something, he is learning to think like the original creator. This is what make him worthy of using the knowledge acquired through that — because it was him who produced that knowledge, even though it may be identical to the knowledge of the original creator.

One doesn't need to think like the original creator in order to read a document. One doesn't need to have any talent to follow direct instructions.

When making games, we don't need to think only about how well developed the game will be, but also about how well developed we will be.

[chao2]

can the sega documentation do more than the kos ?

[dreso741]

KOS provides utility of hardware most common to programmers but, there are a few interesting hardware function that are not usable through KOS right now.

[chao2]

what are some of the interesting hardware function provided?

[dreso741]

So far support for Bump Mapping, and I think Shadows and built-in light isn't supported by KOS. There are also a few more built in features that would be useful for playing video formats.

Also certain supported features are only partially supported. I think fog has extra settings. I'm not going to make a big list of these features because KOS is a pretty big project and looking for everything would take hours.

[bogglez]

Bump mapping, shadows and fog are supported.

[BlueCrab]

So far support for Bump Mapping, and I think Shadows and built-in light isn't supported by KOS. There are also a few more built in features that would be useful for playing video formats.

Also certain supported features are only partially supported. I think fog has extra settings. I'm not going to make a big list of these features because KOS is a pretty big project and looking for everything would take hours.

Gee thanks for that wonderful list of things that are partially missing. At least you could be a bit more specific with your complaints, since you've obviously done at least a bit of research (despite how much you say you despise KOS because of what it is).

That said, there is definitely code out there using KOS for bump mapping, cheap shadows, and the YUV converter (the part about video formats). KOS may not have nice neatly wrapped functions for all of that, but it is entirely possible to do relatively easily. Should KOS have code built-in to handle some of these neatly? Perhaps. However, bump mapping is really the only one (other than cheap shadows which were -- for all intents and purposes -- fully supported already, minus one small function that is a one-liner to set a register) that I think there's much demand for.

Oh, and I guess a bit of thanks are in order for reminding me to finish with the code for cheap shadow support.

[dreso741]

You're acting like a boy. I never stated I despise KOS because of what it is. I explicitly stated twice I respect KOS for what it is.

I'm glad to see a more feature rich support for shadows, but bump maps have a second mode.(also just setting a register) I also feel there should be math functions to manipulate bump maps. YUV conversion probably shouldn't be in KOS because they are almost never used.

[BlueCrab]

You're acting like a boy. I never stated I despise KOS because of what it is. I explicitly stated twice I respect KOS for what it is.

I'm sorry, but I still don't see some of your earlier attacks as anything other than that: attacks. I have only responded in the way that seems fit from my point of view. Each of your posts (from my point of view) simply seems to scream that "KOS Sucks", which as the maintainer and a long-time developer of KOS, I personally feel is an attack on everyone that has contributed to it. There's being constructive with criticism and working to improve the status quo, and then there's what I see from your posts -- which isn't constructive at all. Perhaps the way I've responded is childish, but the way you've presented your arguments here is even moreso, from both my point of view and that of others that have mentioned it to me.

[dreso741]

The only argument that I posted that I see as being childish was the one where I quote snippet's from KOS. But then when I was called out on that I accepted full responsibility for that, and explained that these colloquialisms are considered common speech.

IDK if you saw it. It wasn't directed at you at the time.

It looks like you're offended. I think there has been a miscommunication. This is my fault. The internet is a global platform and, I am used to using a regional slang. I think I should explain myself more clearly. I don't mean everything is shit. If this is what you truly inferred I apologize. Shit is a vulgar word in english but, is also used to mean "a thing" with no negative connotation whatsoever. Real and being real is cultural thing. Many people are fake so, being real or truthful is respected.

I'm not trying to attack KOS. However, at the end of the day we both know there are some really hard to fix bugs in KOS. In actuality I was working on hooking my lib into the PVR functions of KOS (which I still plan todo), that's how my lib started. Despite what I stated multiple times about not wanting to contribute to KOS.

[PH3NOM]

Great work BlueCrab!
When I get a chance I will play around with that "cheap-shadow" demo of yours!

dreso741-
I like your enthusiasm, but from my perspective, you seem to misunderstand the entirety of what we do here.
KOS is a community project.
We work collectively to understand how to make things work, and we contribute our work to benefit the community, in a manner that is possible to release commercial software without worrying about infringing upon intellectual property.

Not just that, but as I have hinted at in the other thread and BlueCrab has mentioned here, nothing you have mentioned is impossible to implement using KOS.

And you have not mentioned some of the really interesting things that KOS can not currently do, such as using the PVR's multi-pass rendering that was discussed in another thread here.

Also, I don't understand what you mean when you say KOS does not have built-in lights.
Lighting is not a feature of the DC's GPU, or CPU, per se.
If you are talking about the use of the PVR's Modifier Volumes to create a "spot light" effect, there is nothing that explicitly stops you from doing that through KOS.
Otherwise, lighting is performed per-vertex on the CPU, obviously you'll want to use the DC's fast (approximate) vector math functions.
Yes, the PVR supports "specular highlights" per-vertex, I guess we could add the ability to enable this in KOS.
There are draw-backs of using the specular in my mind, as you need to clip(float x 4) and clamp(int x 4) an extra set of colors(a r g b) on the CPU, that is why I do not currently use this feature in the GL API.

[dreso741]

I think there is this idea that I'm trying to replace KOS so let me touch on that.

KOS provides an operating system programming environment. So it's good for portability, memory management, debugging, etc. My lib provides an embedded programming experience. So it's good for interfacing the hardware and being stable. I will never allow memory management, debugging, etc. in my code base because it goes against my spec and we have KOS for that. My lib supports multi pass rendering. You can do whatever you want with my lib. You can look at the region array, look at the frame buffer, look at the OPBs, etc.


As far as lighting is concerned I guess you're right. I don't see any documentation for built in lighting. But it was supposed to be feature of the chip. IDK it might still be in there somewhere or maybe they removed it when they put it on the ASIC.


Y'all perspective on legality is baffling to me. Using the architecture documentation is illegal but, using the hitachi manual (which explicitly says you can't use it) is lawful? Also in the thread where you discuss multipass rendering you reference the architecture documentation. All this legal talk seems like self-righteous sassafras.

However, digging deeper, looking at the *document again today, I am beginning to think that the sort mode might actually be ignored in this register,
due to the settings of the FPU_PARAM_CFG, or PVR_UNK_007C.

viewtopic.php?f=29&t=102994&start=20#p1043868




OK. Now I have a story. This is a new level of jackassery. I went to Sega HQ 3 times. It's a 15 min walk from 16th st bart station. Each time I went the President was not there. I talked to some of the senior staff and they told me they didn't have time and went back to watching videos on Youtube. These people don't give a fuck about anything.

On my 3rd visit one person told me that Sega USA has all the legal rights to the Dreamcast but, the licensing agreements of all the dev tools had expired and, that the developer who bought the tools can do whatever they want with them at this point. I have no idea what his job title was so, he could be full of shit.

I also asked when Shenmue 3 would come out and they all ignored me. I also asked when Dreamcast 2 would come out and they all ignored me. They did give me and my friend a t-shirt the 2nd time I came.

tl;dr I went to Sega and all I got was this lousy t-shirt.

[Chilly Willy]

The Hitachi manual is copyrighted by Hitachi, but was released to the public BY HITACHI for free so that programmers could use their processors more easily. Public release is NOT the same thing as public domain. Now the PVR manual has NEVER been released to the public in any form at all - it's still covered under trade secrets. Using a leaked PVR manual is legally iffy where using the Hitachi manuals is perfectly legal... as Hitachi intended. One manufacturer WANTS people to use their manuals (Hitachi), while the other doesn't (NEC).

[Ayla]

The Hitachi manual is copyrighted by Hitachi, but was released to the public BY HITACHI for free so that programmers could use their processors more easily.

Yes. And that's because copyright and license are two different things.

For instance, all the code of KOS is copyrighted but the license allows you to use the code freely in open-source, closed-source and commercial applications.
The Katana code from SEGA is copyrighted, but with a commercial license that does not allow us to use it.

And about the manuals, the Hitashi manual is copyrighted but in public domain so that anybody can use it. The SEGA manuals are copyrighted but not redistribuable.

The copyright is basically a seal that says that the corresponding code or manual belongs to you and nobody can claim otherwise. The license deals with distribution of the product, and the access of the source code.

[dreso741]

Hitachi neither warrants nor grants licenses of any rights of Hitachi’s or any third party’s patent, copyright, trademark, or other intellectual property rights for information contained in this document...

...

No one is permitted to reproduce or duplicate, in any form, the whole or part of this document without written approval from Hitachi.

"It's on their website. Of course you can use it. Why would it be on their website if you can't use it?" But this is what it says in black and white.

Let me explain this because it's probably seems counterintuitive. You can read their documents however, you're not supposed to use their documents to code anything. Confusing right?

Companies will often release data sheets, programming manuals, architecture guides, etc. to encourage other companies to buy their chips/ip. Once you buy the chip/ip they will usually give you the rights to use the manuals to program the chip.

[BlueCrab]

Where in the world do you get the idea that they would put out a manual describing how to program their CPU but make it illegal to use the manual to do just that? Seriously?

Let's look at the blobs of legalese in the current SH4 Software Manual...

Notice
1. All information included in this document is current as of the date this document is issued. Such information, however, is subject to change without any prior notice. Before purchasing or using any Renesas Electronics products listed herein, please confirm the latest product information with a Renesas Electronics sales office. Also, please pay regular and careful attention to additional and different information to be disclosed by Renesas Electronics such as that disclosed through our website.
2. Renesas Electronics does not assume any liability for infringement of patents, copyrights, or other intellectual property rights of third parties by or arising from the use of Renesas Electronics products or technical information described in this document. No license, express, implied or otherwise, is granted hereby under any patents, copyrights or other intellectual property rights of Renesas Electronics or others.
3. You should not alter, modify, copy, or otherwise misappropriate any Renesas Electronics product, whether in whole or in part.
4. Descriptions of circuits, software and other related information in this document are provided only to illustrate the operation of semiconductor products and application examples. You are fully responsible for the incorporation of these circuits, software, and information in the design of your equipment. Renesas Electronics assumes no responsibility for any losses incurred by you or third parties arising from the use of these circuits, software, or information.
5. When exporting the products or technology described in this document, you should comply with the applicable export control laws and regulations and follow the procedures required by such laws and regulations. You should not use Renesas Electronics products or the technology described in this document for any purpose relating to military applications or use by the military, including but not limited to the development of weapons of mass destruction. Renesas Electronics products and technology may not be used for or incorporated into any products or systems whose manufacture, use, or sale is prohibited under any applicable domestic or foreign laws or regulations.
6. Renesas Electronics has used reasonable care in preparing the information included in this document, but Renesas Electronics does not warrant that such information is error free. Renesas Electronics assumes no liability whatsoever for any damages incurred by you resulting from errors in or omissions from the information included herein.
7. Renesas Electronics products are classified according to the following three quality grades: “Standard”, “High Quality”, and “Specific”. The recommended applications for each Renesas Electronics product depends on the product’s quality grade, as indicated below. You must check the quality grade of each Renesas Electronics product before using it in a particular application. You may not use any Renesas Electronics product for any application categorized as “Specific” without the prior written consent of Renesas Electronics. Further, you may not use any Renesas Electronics product for any application for which it is not intended without the prior written consent of Renesas Electronics. Renesas Electronics shall not be in any way liable for any damages or losses incurred by you or third parties arising from the use of any Renesas Electronics product for an application categorized as “Specific” or for which the product is not intended where you have failed to obtain the prior written consent of Renesas Electronics. The quality grade of each Renesas Electronics product is “Standard” unless otherwise expressly specified in a Renesas Electronics data sheets or data books, etc.
“Standard”: Computers; office equipment; communications equipment; test and measurement equipment; audio and visual equipment; home electronic appliances; machine tools; personal electronic equipment; and industrial robots.
“High Quality”: Transportation equipment (automobiles, trains, ships, etc.); traffic control systems; anti-disaster systems; anti- crime systems; safety equipment; and medical equipment not specifically designed for life support.
“Specific”: Aircraft; aerospace equipment; submersible repeaters; nuclear reactor control systems; medical equipment or systems for life support (e.g. artificial life support devices or systems), surgical implantations, or healthcare intervention (e.g. excision, etc.), and any other applications or purposes that pose a direct threat to human life.
8. You should use the Renesas Electronics products described in this document within the range specified by Renesas Electronics, especially with respect to the maximum rating, operating supply voltage range, movement power voltage range, heat radiation characteristics, installation and other product characteristics. Renesas Electronics shall have no liability for malfunctions or damages arising out of the use of Renesas Electronics products beyond such specified ranges.
9. Although Renesas Electronics endeavors to improve the quality and reliability of its products, semiconductor products have specific characteristics such as the occurrence of failure at a certain rate and malfunctions under certain use conditions. Further, Renesas Electronics products are not subject to radiation resistance design. Please be sure to implement safety measures to guard them against the possibility of physical injury, and injury or damage caused by fire in the event of the failure of a Renesas Electronics product, such as safety design for hardware and software including but not limited to redundancy, fire control and malfunction prevention, appropriate treatment for aging degradation or any other appropriate measures. Because the evaluation of microcomputer software alone is very difficult, please evaluate the safety of the final products or system manufactured by you.
10. Please contact a Renesas Electronics sales office for details as to environmental matters such as the environmental compatibility of each Renesas Electronics product. Please use Renesas Electronics products in compliance with all applicable laws and regulations that regulate the inclusion or use of controlled substances, including without limitation, the EU RoHS Directive. Renesas Electronics assumes no liability for damages or losses occurring as a result of your noncompliance with applicable laws and regulations.
11. This document may not be reproduced or duplicated, in any form, in whole or in part, without prior written consent of Renesas Electronics.
12. Please contact a Renesas Electronics sales office if you have any questions regarding the information contained in this document or Renesas Electronics products, or if you have any other inquiries.
(Note 1) “Renesas Electronics” as used in this document means Renesas Electronics Corporation and also includes its majority- owned subsidiaries.
(Note 2) “Renesas Electronics product(s)” means any product developed or manufactured by or for Renesas Electronics.

Unless you're planning to use the product in military equipment, I don't see anything here that implies that you're not allowed to use the manual to program the chip (considering that's exactly what that manual is for).

Now, there's one more blob of legalese before the actual text of the document... So, let's look there:

Keep safety first in your circuit designs!
1. Renesas Technology Corp. puts the maximum effort into making semiconductor products better and more reliable, but there is always the possibility that trouble may occur with them. Trouble with semiconductors may lead to personal injury, fire or property damage.
Remember to give due consideration to safety when making your circuit designs, with appropriate measures such as (i) placement of substitutive, auxiliary circuits, (ii) use of nonflammable material or (iii) prevention against any malfunction or mishap.

Notes regarding these materials
1. These materials are intended as a reference to assist our customers in the selection of the Renesas Technology Corp. product best suited to the customer's application; they do not convey any license under any intellectual property rights, or any other rights, belonging to Renesas Technology Corp. or a third party.
2. Renesas Technology Corp. assumes no responsibility for any damage, or infringement of any third- party's rights, originating in the use of any product data, diagrams, charts, programs, algorithms, or circuit application examples contained in these materials.
3. All information contained in these materials, including product data, diagrams, charts, programs and algorithms represents information on products at the time of publication of these materials, and are subject to change by Renesas Technology Corp. without notice due to product improvements or other reasons. It is therefore recommended that customers contact Renesas Technology Corp. or an authorized Renesas Technology Corp. product distributor for the latest product information before purchasing a product listed herein.
The information described here may contain technical inaccuracies or typographical errors. Renesas Technology Corp. assumes no responsibility for any damage, liability, or other loss rising from these inaccuracies or errors.
Please also pay attention to information published by Renesas Technology Corp. by various means, including the Renesas Technology Corp. Semiconductor home page (http://www.renesas.com).
4. When using any or all of the information contained in these materials, including product data, diagrams, charts, programs, and algorithms, please be sure to evaluate all information as a total system before making a final decision on the applicability of the information and products. Renesas Technology Corp. assumes no responsibility for any damage, liability or other loss resulting from the information contained herein.
5. Renesas Technology Corp. semiconductors are not designed or manufactured for use in a device or system that is used under circumstances in which human life is potentially at stake. Please contact Renesas Technology Corp. or an authorized Renesas Technology Corp. product distributor when considering the use of a product contained herein for any specific purposes, such as apparatus or systems for transportation, vehicular, medical, aerospace, nuclear, or undersea repeater use.
6. The prior written approval of Renesas Technology Corp. is necessary to reprint or reproduce in whole or in part these materials.
7. If these products or technologies are subject to the Japanese export control restrictions, they must be exported under a license from the Japanese government and cannot be imported into a country other than the approved destination.
Any diversion or reexport contrary to the export control laws and regulations of Japan and/or the country of destination is prohibited.
8. Please contact Renesas Technology Corp. for further details on these materials or the products contained therein.

So, here you might be a bit closer, but it'd take a rather gross misreading of note number 1 here (or number 2 in the first block) to even come close to the idea that you're not allowed to use the document to learn how to program the CPU. Nothing in here says you can't use the manual to program the device.

Simply put, the documents are put out there to assist both those evaluating the device for purchases and to assist those who are programming the device. There's absolutely no reason to believe otherwise. Having the manuals doesn't give you any rights to other pieces of intellectual property, such as their compilers/assemblers/etc, but we don't use Renesas/Hitachi's development tools, as there are freely-redistributable alternatives available. That, and Renesas/Hitachi's development tools are based on GCC and friends anyway, IIRC.

As Ayla already said, the Renesas/Hitachi manual is put out there by a company looking to have people use and make use of its products. The Dreamcast Architecture document was an internal company document that was never intended to be released to anyone outside of Sega (hint: It did not come with the dev kits, so it wasn't even meant for 3rd party developers to see). The Renesas/Hitachi manuals are distributed by the company on their website. The architecture document was never distributed by Sega in an authorized fashion to the outside world. The Renesas/Hitachi manual is legal to use to develop software for the hardware. The architecture document is not. That's the reason why I'm all too happy to use the Renesas/Hitachi documents but I won't use the architecture document for my programming.

As has been implied, I'm sure at this point Sega wouldn't care, but what happens if one day they decide they do? Would I want that cloud of doubt hanging over KOS? No. Would I want to set people up to be sued for using KOS? No. That's why I won't use the document (and why I won't allow other things in the repository, such as support for FAT32 filesystems -- at least until the patents covering long filenames expire).

Now, do I care if your goal is to replace KOS? Not really. That's kinda part of the beauty of open-source software. Projects come and go. Projects replace other projects. The world continues turning. Would I potentially be disappointed if one day everyone just mysteriously stopped using KOS in favor of something else? Sure, any developer of an open-source tool would be sad to see all of his users disappear one day, but guess what, that'd just drive me to improve my offering even more.

[dreso741]

...assist our customers in the selection of the Renesas Technology Corp. product best suited to the customer's application; they do not convey any license under any intellectual property rights, or any other rights, belonging to Renesas Technology Corp. or a third party.

The manual says exactly what I stated. We haven't bought the chip/ip. We aren't customers. We have no rights to use these manuals.


You obviously really care about KOS and it's goals and, I find that commendable. However, all the evidence that these document's are legal to use is purely anecdotal or hearsay. This is just how the EE world works. I know it's confusing.

[Jae686]

So Dreso741, when will we be able to try out your lib ?

Best Regards.

[BlueCrab]

...assist our customers in the selection of the Renesas Technology Corp. product best suited to the customer's application; they do not convey any license under any intellectual property rights, or any other rights, belonging to Renesas Technology Corp. or a third party.

The manual says exactly what I stated. We haven't bought the chip/ip. We aren't customers. We have no rights to use these manuals.

That is not what that means. I'm sorry, but your understanding of the legalese is just plain wrong.

Why don't you try sending Renesas an email asking them if it is legal to use the manuals from their site to develop software for their CPUs, if you're so concerned that it isn't? I'm going to guess that they'll probably kindly send you an email back stating that yes, it is indeed legal to use their manuals to develop software for their CPUs, otherwise why would they release the manuals? Developing software without the aid of any of Renesas' copyrighted software is perfectly legal and nothing in that legalese says otherwise. As I said before, it would take a gross misreading of the terms to get that idea. The terms basically say that having the manual doesn't give you the right to use their proprietary compilers/software. We're not using any of that, and never have.

Obviously nobody else shares your opinion on the legality of using the Renesas manual, just like most of us don't seem to share your opinion on the legality of using the Sega architecture document.

[dreso741]

So Dreso741, when will we be able to try out your lib ?

Best Regards.

I hope to go into an open testing phase of the graphics module by christmas, but I could always use help with testing, documentation, etc. If you're interested in that PM me and I'll get back to you.