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Game Developers Conference Europe Wrap, New Women’S Group Forms, Licensed to Steal Super Genre Break Out, and More
>> PRODUCT REVIEWS SPEEDTREE RT 1.7 * SPACEPILOT OCTOBER 2005 THE LEADING GAME INDUSTRY MAGAZINE >>POSTMORTEM >>WALKING THE PLANK >>INNER PRODUCT ART & ARTIFICE IN DANIEL JAMES ON DEBUG? RELEASE? RESIDENT EVIL 4 CASUAL MMO GOLD LET’S DEVELOP! Thanks to our publishers for helping us create a new world of video games. GameTapTM and many of the video game industry’s leading publishers have joined together to create a new world where you can play hundreds of the greatest games right from your broadband-connected PC. It’s gaming freedom like never before. START PLAYING AT GAMETAP.COM TM & © 2005 Turner Broadcasting System, Inc. A Time Warner Company. Patent Pending. All Rights Reserved. GTP1-05-116-104_mstrA_v2.indd 1 9/7/05 10:58:02 PM []CONTENTS OCTOBER 2005 VOLUME 12, NUMBER 9 FEATURES 11 TOP 20 PUBLISHERS Who’s the top dog on the publishing block? Ranked by their revenues, the quality of the games they release, developer ratings, and other factors pertinent to serious professionals, our annual Top 20 list calls attention to the definitive movers and shakers in the publishing world. 11 By Tristan Donovan 21 INTERVIEW: A PIRATE’S LIFE What do pirates, cowboys, and massively multiplayer online games have in common? They all have Daniel James on their side. CEO of Three Rings, James’ mission has been to create an addictive MMO (or two) that has the pick-up-put- down rhythm of a casual game. In this interview, James discusses the barriers to distributing and charging for such 21 games, the beauty of the web, and the trouble with executables. -
GAME DEVELOPERS a One-Of-A-Kind Game Concept, an Instantly Recognizable Character, a Clever Phrase— These Are All a Game Developer’S Most Valuable Assets
HOLLYWOOD >> REVIEWS ALIAS MAYA 6 * RTZEN RT/SHADER ISSUE AUGUST 2004 THE LEADING GAME INDUSTRY MAGAZINE >>SIGGRAPH 2004 >>DEVELOPER DEFENSE >>FAST RADIOSITY SNEAK PEEK: LEGAL TOOLS TO SPEEDING UP LIGHTMAPS DISCREET 3DS MAX 7 PROTECT YOUR I.P. WITH PIXEL SHADERS POSTMORTEM: THE CINEMATIC EFFECT OF ZOMBIE STUDIOS’ SHADOW OPS: RED MERCURY []CONTENTS AUGUST 2004 VOLUME 11, NUMBER 7 FEATURES 14 COPYRIGHT: THE BIG GUN FOR GAME DEVELOPERS A one-of-a-kind game concept, an instantly recognizable character, a clever phrase— these are all a game developer’s most valuable assets. To protect such intangible properties from pirates, you’ll need to bring out the big gun—copyright. Here’s some free advice from a lawyer. By S. Gregory Boyd 20 FAST RADIOSITY: USING PIXEL SHADERS 14 With the latest advances in hardware, GPU, 34 and graphics technology, it’s time to take another look at lightmapping, the divine art of illuminating a digital environment. By Brian Ramage 20 POSTMORTEM 30 FROM BUNGIE TO WIDELOAD, SEROPIAN’S BEAT GOES ON 34 THE CINEMATIC EFFECT OF ZOMBIE STUDIOS’ A decade ago, Alexander Seropian founded a SHADOW OPS: RED MERCURY one-man company called Bungie, the studio that would eventually give us MYTH, ONI, and How do you give a player that vicarious presence in an imaginary HALO. Now, after his departure from Bungie, environment—that “you-are-there” feeling that a good movie often gives? he’s trying to repeat history by starting a new Zombie’s answer was to adopt many of the standard movie production studio: Wideload Games. -
Steve Marschner CS5625 Spring 2019 Predicting Reflectance Functions from Complex Surfaces
08 Detail mapping Steve Marschner CS5625 Spring 2019 Predicting Reflectance Functions from Complex Surfaces Stephen H. Westin James R. Arvo Kenneth E. Torrance Program of Computer Graphics Cornell University Ithaca, New York 14853 Hierarchy of scales Abstract 1000 macroscopic Geometry We describe a physically-based Monte Carlo technique for ap- proximating bidirectional reflectance distribution functions Object scale (BRDFs) for a large class of geometriesmesoscopic by directly simulating 100 optical scattering. The technique is more general than pre- vious analytical models: it removesmicroscopic most restrictions on sur- Texture, face microgeometry. Three main points are described: a new bump maps 10 representation of the BRDF, a Monte Carlo technique to esti- mate the coefficients of the representation, and the means of creating a milliscale BRDF from microscale scattering events. Milliscale These allow the prediction of scattering from essentially ar- (Mesoscale) 1 mm Texels bitrary roughness geometries. The BRDF is concisely repre- sented by a matrix of spherical harmonic coefficients; the ma- 0.1 trix is directly estimated from a geometric optics simulation, BRDF enforcing exact reciprocity. The method applies to rough- ness scales that are large with respect to the wavelength of Microscale light and small with respect to the spatial density at which 0.01 the BRDF is sampled across the surface; examples include brushed metal and textiles. The method is validated by com- paring with an existing scattering model and sample images are generated with a physically-based global illumination al- Figure 1: Applicability of Techniques gorithm. CR Categories and Subject Descriptors: I.3.7 [Computer model many surfaces, such as those with anisotropic rough- Graphics]: Three-Dimensional Graphics and Realism. -
9.Texture Mapping
OpenGL_PG.book Page 359 Thursday, October 23, 2003 3:23 PM Chapter 9 9.Texture Mapping Chapter Objectives After reading this chapter, you’ll be able to do the following: • Understand what texture mapping can add to your scene • Specify texture images in compressed and uncompressed formats • Control how a texture image is filtered as it’s applied to a fragment • Create and manage texture images in texture objects and, if available, control a high-performance working set of those texture objects • Specify how the color values in the image combine with those of the fragment to which it’s being applied • Supply texture coordinates to indicate how the texture image should be aligned with the objects in your scene • Generate texture coordinates automatically to produce effects such as contour maps and environment maps • Perform complex texture operations in a single pass with multitexturing (sequential texture units) • Use texture combiner functions to mathematically operate on texture, fragment, and constant color values • After texturing, process fragments with secondary colors • Perform transformations on texture coordinates using the texture matrix • Render shadowed objects, using depth textures 359 OpenGL_PG.book Page 360 Thursday, October 23, 2003 3:23 PM So far, every geometric primitive has been drawn as either a solid color or smoothly shaded between the colors at its vertices—that is, they’ve been drawn without texture mapping. If you want to draw a large brick wall without texture mapping, for example, each brick must be drawn as a separate polygon. Without texturing, a large flat wall—which is really a single rectangle—might require thousands of individual bricks, and even then the bricks may appear too smooth and regular to be realistic. -
Programming Guide: Revision 1.4 June 14, 1999 Ccopyright 1998 3Dfxo Interactive,N Inc
Voodoo3 High-Performance Graphics Engine for 3D Game Acceleration June 14, 1999 al Voodoo3ti HIGH-PERFORMANCEopy en GdRAPHICS E NGINEC FOR fi ot 3D GAME ACCELERATION on Programming Guide: Revision 1.4 June 14, 1999 CCopyright 1998 3Dfxo Interactive,N Inc. All Rights Reserved D 3Dfx Interactive, Inc. 4435 Fortran Drive San Jose CA 95134 Phone: (408) 935-4400 Fax: (408) 935-4424 Copyright 1998 3Dfx Interactive, Inc. Revision 1.4 Proprietary and Preliminary 1 June 14, 1999 Confidential Voodoo3 High-Performance Graphics Engine for 3D Game Acceleration Notice: 3Dfx Interactive, Inc. has made best efforts to ensure that the information contained in this document is accurate and reliable. The information is subject to change without notice. No responsibility is assumed by 3Dfx Interactive, Inc. for the use of this information, nor for infringements of patents or the rights of third parties. This document is the property of 3Dfx Interactive, Inc. and implies no license under patents, copyrights, or trade secrets. Trademarks: All trademarks are the property of their respective owners. Copyright Notice: No part of this publication may be copied, reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photographic, or otherwise, or used as the basis for manufacture or sale of any items without the prior written consent of 3Dfx Interactive, Inc. If this document is downloaded from the 3Dfx Interactive, Inc. world wide web site, the user may view or print it, but may not transmit copies to any other party and may not post it on any other site or location. -
Antialiasing
Antialiasing CSE 781 Han-Wei Shen What is alias? Alias - A false signal in telecommunication links from beats between signal frequency and sampling frequency (from dictionary.com) Not just telecommunication, alias is everywhere in computer graphics because rendering is essentially a sampling process Examples: Jagged edges False texture patterns Alias caused by under-sampling 1D signal sampling example Actual signal Sampled signal Alias caused by under-sampling 2D texture display example Minor aliasing worse aliasing How often is enough? What is the right sampling frequency? Sampling theorem (or Nyquist limit) - the sampling frequency has to be at least twice the maximum frequency of the signal to be sampled Need two samples in this cycle Reconstruction After the (ideal) sampling is done, we need to reconstruct back the original continuous signal The reconstruction is done by reconstruction filter Reconstruction Filters Common reconstruction filters: Box filter Tent filter Sinc filter = sin(πx)/πx Anti-aliased texture mapping Two problems to address – Magnification Minification Re-sampling Minification and Magnification – resample the signal to a different resolution Minification Magnification (note the minification is done badly here) Magnification Simpler to handle, just resample the reconstructed signal Reconstructed signal Resample the reconstructed signal Magnification Common methods: nearest neighbor (box filter) or linear interpolation (tent filter) Nearest neighbor bilinear interpolation Minification Harder to handle The signal’s frequency is too high to avoid aliasing A possible solution: Increase the low pass filter width of the ideal sinc filter – this effectively blur the image Blur the image first (using any method), and then sample it Minification Several texels cover one pixel (under sampling happens) Solution: Either increase sampling rate or reduce the texture Frequency one pixel We will discuss: Under sample artifact 1. -
Power Optimizations for Graphics Processors
POWER OPTIMIZATIONS FOR GRAPHICS PROCESSORS B.V.N.SILPA DEPARTMENT OF COMPUTER SCIENCE & ENGINEERING INDIAN INSTITUTE OF TECHNOLOGY DELHI March 2011 POWER OPTIMAZTIONS FOR GRAPHICS PROCESSORS by B.V.N.SILPA Department of Computer Science and Engineering Submitted in fulfillment of the requirements of the degree of Doctor of Philosophy to the Indian Institute of Technology Delhi March 2011 Certificate This is to certify that the thesis titled Power optimizations for graphics pro- cessors being submitted by B V N Silpa for the award of Doctor of Philosophy in Computer Science & Engg. is a record of bona fide work carried out by her under my guidance and supervision at the Deptartment of Computer Science & Engineer- ing, Indian Institute of Technology Delhi. The work presented in this thesis has not been submitted elsewhere, either in part or full, for the award of any other degree or diploma. Preeti Ranjan Panda Professor Dept. of Computer Science & Engg. Indian Institute of Technology Delhi Acknowledgment It is with immense gratitude that I acknowledge the support and help of my Professor Preeti Ranjan Panda in guiding me through this thesis. I would like to thank Professors M. Balakrishnan, Anshul Kumar, G.S. Visweswaran and Kolin Paul for their valuable feedback, suggestions and help in all respects. I am indebted to my dear friend G Kr- ishnaiah for being my constant support and an impartial critique. I would like to thank Neeraj Goel, Anant Vishnoi and Aryabartta Sahu for their technical and moral support. I would also like to thank the staff of Philips, FPGA, Intel laboratories and IIT Delhi for their help. -
Texture Filtering Jim Van Verth Some Definitions
Texture Filtering Jim Van Verth Some definitions Pixel: picture element. On screen. Texel: texture element. In image (AKA texture). Suppose we have a texture (represented here in blue). We can draw the mapping from a pixel to this space, and represent it as a red square. If our scale from pixel space to texel space is 1:1, with no translation, we just cover one texel, so rendering is easy. If we translate, the pixel can cover more than one texel, with different areas. If we rotate, then the pixel can cover even more texels, with odd shaped areas. And with scaling up the texture (which scales down the pixel area in texture space)... ...or scaling down the texture (which scales up the pixel area in texture space), we also get different types of coverage. So what are we trying to do? We often think of a texture like this -- blocks of “color” (we’ll just assume the texture is grayscale in these diagrams to keep it simple). But really, those blocks represent a sample at the texel center. So what we really have is this. Those samples are snapshots of some function, at a uniform distance apart. We don’t really know what the function is, but assuming it’s fairly smooth it could look something like this. So our goal is to reconstruct this function from the samples, so we can compute in-between values. We can draw our pixel (in 1D form) on this graph. Here the red lines represent the boundary of the pixel in texture space. -
Procedural Modeling
Procedural Modeling From Last Time • Many “Mapping” techniques – Bump Mapping – Normal Mapping – Displacement Mapping – Parallax Mapping – Environment Mapping – Parallax Occlusion – Light Mapping Mapping Bump Mapping • Use textures to alter the surface normal – Does not change the actual shape of the surface – Just shaded as if it were a different shape Sphere w/Diffuse Texture Swirly Bump Map Sphere w/Diffuse Texture & Bump Map Bump Mapping • Treat a greyscale texture as a single-valued height function • Compute the normal from the partial derivatives in the texture Another Bump Map Example Bump Map Cylinder w/Diffuse Texture Map Cylinder w/Texture Map & Bump Map Normal Mapping • Variation on Bump Mapping: Use an RGB texture to directly encode the normal http://en.wikipedia.org/wiki/File:Normal_map_example.png What's Missing? • There are no bumps on the silhouette of a bump-mapped or normal-mapped object • Bump/Normal maps don’t allow self-occlusion or self-shadowing From Last Time • Many “Mapping” techniques – Bump Mapping – Normal Mapping – Displacement Mapping – Parallax Mapping – Environment Mapping – Parallax Occlusion – Light Mapping Mapping Displacement Mapping • Use the texture map to actually move the surface point • The geometry must be displaced before visibility is determined Displacement Mapping Image from: Geometry Caching for Ray-Tracing Displacement Maps EGRW 1996 Matt Pharr and Pat Hanrahan note the detailed shadows cast by the stones Displacement Mapping Ken Musgrave a.k.a. Offset Mapping or Parallax Mapping Virtual Displacement Mapping • Displace the texture coordinates for each pixel based on view angle and value of the height map at that point • At steeper view-angles, texture coordinates are displaced more, giving illusion of depth due to parallax effects “Detailed shape representation with parallax mapping”, Kaneko et al. -
Per-Pixel Displacement Mapping with Distance Functions
108_gems2_ch08_new.qxp 2/2/2005 2:20 PM Page 123 Chapter 8 Per-Pixel Displacement Mapping with Distance Functions William Donnelly University of Waterloo In this chapter, we present distance mapping, a technique for adding small-scale dis- placement mapping to objects in a pixel shader. We treat displacement mapping as a ray-tracing problem, beginning with texture coordinates on the base surface and calcu- lating texture coordinates where the viewing ray intersects the displaced surface. For this purpose, we precompute a three-dimensional distance map, which gives a measure of the distance between points in space and the displaced surface. This distance map gives us all the information necessary to quickly intersect a ray with the surface. Our algorithm significantly increases the perceived geometric complexity of a scene while maintaining real-time performance. 8.1 Introduction Cook (1984) introduced displacement mapping as a method for adding small-scale detail to surfaces. Unlike bump mapping, which affects only the shading of surfaces, displacement mapping adjusts the positions of surface elements. This leads to effects not possible with bump mapping, such as surface features that occlude each other and nonpolygonal silhouettes. Figure 8-1 shows a rendering of a stone surface in which occlusion between features contributes to the illusion of depth. The usual implementation of displacement mapping iteratively tessellates a base sur- face, pushing vertices out along the normal of the base surface, and continuing until 8.1 Introduction 123 Copyright 2005 by NVIDIA Corporation 108_gems2_ch08_new.qxp 2/2/2005 2:20 PM Page 124 Figure 8-1. A Displaced Stone Surface Displacement mapping (top) gives an illusion of depth not possible with bump mapping alone (bottom). -
Voodoo Graphics Specification
SST-1(a.k.a. Voodoo Graphics™) HIGH PERFORMANCE GRAPHICS ENGINE FOR 3D GAME ACCELERATION Revision 1.61 December 1, 1999 Copyright ã 1995 3Dfx Interactive, Inc. All Rights Reserved 3dfx Interactive, Inc. 4435 Fortran Drive San Jose, CA 95134 Phone: (408) 935-4400 Fax: (408) 262-8602 www.3dfx.com Proprietary Information SST-1 Graphics Engine for 3D Game Acceleration Copyright Notice: [English translations from legalese in brackets] ©1996-1999, 3Dfx Interactive, Inc. All rights reserved This document may be reproduced in written, electronic or any other form of expression only in its entirety. [If you want to give someone a copy, you are hereby bound to give him or her a complete copy.] This document may not be reproduced in any manner whatsoever for profit. [If you want to copy this document, you must not charge for the copies other than a modest amount sufficient to cover the cost of the copy.] No Warranty THESE SPECIFICATIONS ARE PROVIDED BY 3DFX "AS IS" WITHOUT ANY REPRESENTATION OR WARRANTY, EXPRESS OR IMPLIED, INCLUDING ANY WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NONINFRINGEMENT OF THIRD-PARTY INTELLECTUAL PROPERTY RIGHTS, OR ARISING FROM THE COURSE OF DEALING BETWEEN THE PARTIES OR USAGE OF TRADE. IN NO EVENT SHALL 3DFX BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING, WITHOUT LIMITATION, DIRECT OR INDIRECT DAMAGES, DAMAGES FOR LOSS OF PROFITS, BUSINESS INTERRUPTION, OR LOSS OF INFORMATION) ARISING OUT OF THE USE OF OR INABILITY TO USE THE SPECIFICATIONS, EVEN IF 3DFX HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. [You're getting it for free. -
Analytic Displacement Mapping Using Hardware Tessellation
Analytic Displacement Mapping using Hardware Tessellation Matthias Nießner University of Erlangen-Nuremberg and Charles Loop Microsoft Research Displacement mapping is ideal for modern GPUs since it enables high- 1. INTRODUCTION frequency geometric surface detail on models with low memory I/O. How- ever, problems such as texture seams, normal re-computation, and under- Displacement mapping has been used as a means of efficiently rep- sampling artifacts have limited its adoption. We provide a comprehensive resenting and animating 3D objects with high frequency surface solution to these problems by introducing a smooth analytic displacement detail. Where texture mapping assigns color to surface points at function. Coefficients are stored in a GPU-friendly tile based texture format, u; v parameter values, displacement mapping assigns vector off- and a multi-resolution mip hierarchy of this function is formed. We propose sets. The advantages of this approach are two-fold. First, only the a novel level-of-detail scheme by computing per vertex adaptive tessellation vertices of a coarse (low frequency) base mesh need to be updated factors and select the appropriate pre-filtered mip levels of the displace- each frame to animate the model. Second, since the only connec- ment function. Our method obviates the need for a pre-computed normal tivity data needed is for the coarse base mesh, significantly less map since normals are directly derived from the displacements. Thus, we space is needed to store the equivalent highly detailed mesh. Fur- are able to perform authoring and rendering simultaneously without typical ther space reductions are realized by storing scalar, rather than vec- displacement map extraction from a dense triangle mesh.