• 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
Funkymunky

unbind VBO, draw vertex array, rebind VBO?

3 posts in this topic

If I'm drawing a whole bunch of data from a VBO, is it terrible practice to unbind the VBO, render some stuff with a standard vertex array, then rebind the VBO and continue drawing from it?  Or is it better to just switch to a different VBO for that middle render?

0

Share this post


Link to post
Share on other sites

In the modern API, you are required to use VBO for all vertex arrays, so if you can use VBO then there's no reason why you should use VBO for only some of your vertex arrays. Get in line with the new API and use VBO for all your vertex arrays.

0

Share this post


Link to post
Share on other sites
In the modern API, you are required to use VBO for all vertex arrays, so if you can use VBO then there's no reason why you should use VBO for only some of your vertex arrays. Get in line with the new API and use VBO for all your vertex arrays.

 

The core profile for OpenGL 4.3 says no such thing. Certainly the old fixed function pointer methods have been removed (e.g. glVertexPointer), but glVertexAttribPointer can be used to specify system memory based vertex arrays. Even glVertexAttrib3f() is still part of the core spec. There is what seems to be a typo in the online GL docs, where is says the INVALID_OPERATION will be generated if no ARRAY_BUFFER is bound, and the pointer is not NULL (which makes no sense, since that would mean using 0 for the array buffer, and null for the pointer would be valid). I'm guessing that's where the confusion has arisen from.

0

Share this post


Link to post
Share on other sites
In the modern API, you are required to use VBO for all vertex arrays, so if you can use VBO then there's no reason why you should use VBO for only some of your vertex arrays. Get in line with the new API and use VBO for all your vertex arrays.

 

The core profile for OpenGL 4.3 says no such thing. Certainly the old fixed function pointer methods have been removed (e.g. glVertexPointer), but glVertexAttribPointer can be used to specify system memory based vertex arrays.

Version 4.3 core specification, section 10.8.3, page 304; last sentence says "If any enabled array’s buffer binding is zero when DrawArrays or one of the
other drawing commands defined in section 10.5 is called, the result is undefined
." Thus, it is an error to draw with the zero-buffer bound; an array must therefore have a non-zero buffer binding.

 

There is what seems to be a typo in the online GL docs, where is says the INVALID_OPERATION will be generated if no ARRAY_BUFFER is bound, and the pointer is not NULL (which makes no sense, since that would mean using 0 for the array buffer, and null for the pointer would be valid). I'm guessing that's where the confusion has arisen from.

Even the specification itself says that: page 299 in the definition of glVertexAttribArray.
 

Even glVertexAttrib3f() is still part of the core spec.

glVertexAttrib*() is used to set the default attribute value for attributes that doesn't have an enabled buffer attached to it. I don't see what it has to do with my comment you questioned though.

0

Share this post


Link to post
Share on other sites

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
Sign in to follow this  
Followers 0