• Announcements

    • khawk

      Download the Game Design and Indie Game Marketing Freebook   07/19/17

      GameDev.net and CRC Press have teamed up to bring a free ebook of content curated from top titles published by CRC Press. The freebook, Practices of Game Design & Indie Game Marketing, includes chapters from The Art of Game Design: A Book of Lenses, A Practical Guide to Indie Game Marketing, and An Architectural Approach to Level Design. The GameDev.net FreeBook is relevant to game designers, developers, and those interested in learning more about the challenges in game development. We know game development can be a tough discipline and business, so we picked several chapters from CRC Press titles that we thought would be of interest to you, the GameDev.net audience, in your journey to design, develop, and market your next game. The free ebook is available through CRC Press by clicking here. The Curated Books The Art of Game Design: A Book of Lenses, Second Edition, by Jesse Schell Presents 100+ sets of questions, or different lenses, for viewing a game’s design, encompassing diverse fields such as psychology, architecture, music, film, software engineering, theme park design, mathematics, anthropology, and more. Written by one of the world's top game designers, this book describes the deepest and most fundamental principles of game design, demonstrating how tactics used in board, card, and athletic games also work in video games. It provides practical instruction on creating world-class games that will be played again and again. View it here. A Practical Guide to Indie Game Marketing, by Joel Dreskin Marketing is an essential but too frequently overlooked or minimized component of the release plan for indie games. A Practical Guide to Indie Game Marketing provides you with the tools needed to build visibility and sell your indie games. With special focus on those developers with small budgets and limited staff and resources, this book is packed with tangible recommendations and techniques that you can put to use immediately. As a seasoned professional of the indie game arena, author Joel Dreskin gives you insight into practical, real-world experiences of marketing numerous successful games and also provides stories of the failures. View it here. An Architectural Approach to Level Design This is one of the first books to integrate architectural and spatial design theory with the field of level design. The book presents architectural techniques and theories for level designers to use in their own work. It connects architecture and level design in different ways that address the practical elements of how designers construct space and the experiential elements of how and why humans interact with this space. Throughout the text, readers learn skills for spatial layout, evoking emotion through gamespaces, and creating better levels through architectural theory. View it here. Learn more and download the ebook by clicking here. Did you know? GameDev.net and CRC Press also recently teamed up to bring GDNet+ Members up to a 20% discount on all CRC Press books. Learn more about this and other benefits here.
Sign in to follow this  
Followers 0
  • entries
  • comments
  • views

misc: added more features for BTIC1C...

Sign in to follow this  
Followers 0


well, the BTIC3A effort also kind of stalled out, mostly as the format turns out to be overly complex to implement (particularly on the encoder). I may revive the effort later, or maybe try again with a simpler design (leaving blocks in raster order and probably designing it to be easier to encode with a multi-stage encoder).

so, I ended up for now just going and doing something lazier:
gluing a few more things onto my existing BTIC1C format.

these are:
predicted / differential colors (saves bits by storing many colors as an approximate delta value);
support for 2x2 pixel blocks (as a compromise between flat-color blocks and 4x4 pixel blocks, a 2x2 pixel block needs 8 bits rather than 32 bits);
simplistic motion compensation (blocks from prior frames may be translated into the new frame).

all were pretty lazy, most worked ok.

the differential colors are a bit problematic though as they are prone to mess up resulting in graphical glitches (blocks which seem to overflow/underflow the color values, or result in miscolored splotches);

basically, it uses a Paeth filter (like in PNG), and tries to predict the block colors from adjacent blocks, which allows (in premise), the use of 7-bit color deltas (as a 5x5x5 cube) instead of full RGB555 colors in many cases.

I suspect there is a divergence though between the encoder-side blocks and decoder-side blocks though, to account for the colors screwing up (the blocks as they come out of the quantizer look fine though, implying that the deltas and quantization are not themselves at fault).

the 2x2 blocks and motion compensation were each a little more effective. while not pixel-accurate, the motion compensation can at least sort of deal with general movement and seems better than having nothing at all.

I suspect in general it is doing "ok" with size/quality in that I can have a 2 minute video in 50MB at 512x512 and not have it look entirely awful.

decided to run a few benchmarks, partly to verify some of my new features didn't kill decode performance.

non-Deflated version:
decode speed to RGBA: ~ 140 Mpix/sec;
decode speed to DXT5: ~ 670 Mpix/sec.

Deflated version:
decode speed to RGBA: ~ 118 Mpix/sec;
decode speed to DXT5: ~ 389 Mpix/sec.

then started wondering what would be the results of trying a multi-threaded decoder (with 4 decoder threads):
420 Mpix/sec to RGBA;
2100 Mpix/sec DXT5 (IOW: approx 2.1 gigapixels per second).

this is for a non-Deflated version, as for the Deflated version, performance kind of goes to crap as the threads end up all ramming into a mutex protecting the inflater (not currently thread safe).

or such...

BTIC1C spec (working draft):

BTIC3A partial spec (idea spec):
(doesn't seem like much, but the issues are more subtle).

well, it looks like 3A may not be entirely dead, there are a few parts I am considering trying to "generalize out", so it may not all be loss. for example, the bitstream code was originally generalized somewhat (mostly as I was like "you know what, copy-pasting a lot of this is getting stupid", as well as it still shares some structures with BTIC2C).

likewise, I may generalize out the use of 256-bit meta-blocks on the encoder end (rather than a 128-bit block format), partly as the format needs to deal both with representing pixel data, and also some amount of internal metadata (mostly related to the block quantizer), and 256-bits provides a little more room to work with.

don't know yet if this could lead to a (probably less ambitious) 3B effort, or what exactly this would look like (several possibilities exist). partly tempted by thoughts of maybe using a PNG-like or DWT-based transform for the block colors.

Sign in to follow this  
Followers 0


There are no comments to display.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now