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      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.
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thedodgeruk

early return from GPU does not speed up process ?

2 posts in this topic

i am doing shader work  in the geometry shader  a particle system and thought that doing a check at the beginning and doing an early return  then it would speed up the whole  project .

i found that no speed improvement was made.

 

i even tryed doing  a modular test so it would return every time apart from the 1000 particle , it still made no difference 

 

what can i do  for early return so that it will speed up the process ?

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Threads run in SIMD lock-step, meaning that every thread needs to execute the exact same instruction at the same time. Obviously we have if statements where half the threads will go one way and the other half will go another. What the GPU does is insert a nop (no operation) for failed cases and execute BOTH branches. If half the threads are false and go to the else then they will execute nops while the other half does the code in the if block, then they will switch roles and the first half will perform the else operations while the other half performs nops.

 

Now imagine you have 999 threads that exit early and 1 that does not. All 1000 threads will have to execute the longest path!

 

NVIDIA GPUs break the problem into threadgroups which execute together. If you can get the early terminators to be in the same threadgroup then the computation will actually speed up. If you can't then there is no performance increase.

Edited by menohack
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