• 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

Deferred rendering basics

2 posts in this topic

I'm trying to implement deferred rendering and I'm stuck with this problem. I do all calculations in view space, I set the light position for testing to (0,0,0) - camera position. But the problem is when I look up or down the lighting changes to brighter or darker. It sounds like I have something wrong with matrices but I checked that many times and still no luck. I'm not sure if my reconstruction from depth is right because it's a new thing to me and I may be doing something wrong here. But on the other hand lighting doesn't change when I move backward or forward and keep the angle (so I guess position is correct?). Anyway I'm posting some pictures, maybe someone can figure out where I go wrong. For now I'm trying to compute lighting with geometry normals and then move with bump maps. To me my normals look too bright, pinkish, dull etc. when I compare them to normals from Killzone paper or other tutorials. Maybe this is the case?

Thanks for watching

Edit: I consider simplest scenario for now - only diffuse lighting, no attenuation, no specular and no ambient

This is how I recreate position from depth in light pass:
float z = f1tex2D(depth_map, texCoord);
float x = texCoord.x * 2 - 1;
float y = (1 - texCoord.y) * 2 - 1;
float4 vProjectedPos = float4(x, y, z, 1.0f);
//unproject the position from clip space to view space using inv. proj. matrix
float4 vPositionVS = mul(invProj, vProjectedPos);
float3 vsPos = vPositionVS.xyz / vPositionVS.w;

I use depth buffer to get depth or I can use depth encoded as color which is:
in vertex program:
[CODE]outPosition = mul(ModelViewProj, position);
vDepthCS.xy = outPosition.zw;[/CODE]

and in fragment program I do division z/w and pack it as color but the result is the same as with depth buffer. Edited by keym

Share this post

Link to post
Share on other sites
First off, you can't display the normals without hack, because normals have negative values. Therefore you need to map them to a visible colorspace (color = normal*0.5+0.5), I guess that killzone use an other mapping(or none at all).

Your normal screenshot seems to be ok (green pointing up, red pointing right, blue tint for pointing to the camera), how does the normals change if you look up/down, maybe your inversion of the y-coord is not consistent. Edited by Ashaman73

Share this post

Link to post
Share on other sites
I solved my problem yesterday. Normals were ok (I packed and unpacked them from color with that hack you mention but I didn't mention that, that Killzone paper made me doubt...). Turned out that my reconstruction of position was wrong (like said before, it's a new thing to me and I was unsure of that bit the most). I used this [url="http://www.opengl.org/discussion_boards/showthread.php/177001-Easiest-way-to-reconstruct-eye-space-position?p=1234440&viewfull=1#post1234440"]http://www.opengl.or...l=1#post1234440[/url] code and it finally worked [img]http://public.gamedev.net//public/style_emoticons/default/smile.png[/img]. Thanks for interest though.


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