• 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.

Archived

This topic is now archived and is closed to further replies.

stefu

Directional light in OGL vs D3D

2 posts in this topic

Finally I got my OpenGL lighting to work somehow in my GFX wrapper (supports OGL and D3D). This is fun: In OpenGL I must set light direction to point opposite direction than in D3D. Why? I can do it so but it bothers me if I don''t know why. In D3D I do all right, there''s no question about it I think the OpenGL lighting system is a bit of mystery. The light must be set every frame after view matrix is set by camera to make light fixed in scene.
0

Share this post


Link to post
Share on other sites
The Z axis is pointing in the opposite direction in OpenGL than the D3D default. This could explain why you have set the light in the "opposite" direction.

The light position is transformed by the contents of the current top of the ModelView matrix stack when you specify the light position with a call to glLightfv(GL_LIGHT_POSITION,…). You may or may not have to set the light position each frame depending on what you want the light be fixed to.
The OpenGL FAQ has a good discussion about this
http://www.frii.com/~martz/oglfaq/lights.htm#ligh0050

As far as I know is OpenGL and D3D lights identical.
0

Share this post


Link to post
Share on other sites
This is one I never understood. They say that OGL uses right-handed and D3D left-handed coord system. For OGL it is true, but I use right-handed coord system also in D3D. So Z -axis points towards me out of the monitor in both APIs. and X goes right and y up. In D3DX there are functions for bot LH and RH and I never had to change any vertex or normal data before so I don''t think that''s the problem.

If the Z was pointing opposite direction, I think it should be enought to change z-value of direction vector. (?) But I have to multiply (x,y,z) by -1.
0

Share this post


Link to post
Share on other sites