http://blog.gmane.org/gmane.games.devel.algorithms hourly 1 1901-01-01T00:00+00:00 http://gmane.org/img/gmane-25t.png http://gmane.org http://comments.gmane.org/gmane.games.devel.algorithms/22084 <pre>Hi. Sorry for this OT, but I need to know from the experts. Do you know which software generates backgrounds like in Bejeweled? Thanks. Jose------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/_______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list</pre> Jose Marin 2012-04-28T10:36:57 http://comments.gmane.org/gmane.games.devel.algorithms/22083 <pre> CALL FOR PAPERS - INTERNATIONAL JOURNAL OF ARTIFICIAL INTELLIGENCE AND EXPERT SYSTEMS (IJAE) ISSN: 2180-124X Volume 3, Issue 3 Info. at http://www.cscjournals.org/csc/journals/IJAE/journal_cfp.php?JCode=IJAE Computer Science Journals (CSC Journals) invites researchers, editors, scientists &amp; scholars to publish their scientific research papers in an International Journal of Artificial Intelligence and Expert Systems (IJAE) Volume 3, Issue 3. The main aim of the International Journal of Artificial Intelligence and Expert Systems (IJAE) is to provide a platform to AI &amp; Expert Systems (ES) scientists and professionals to share their research and report new advances in the field of AI and ES. IJAE is a refereed journal producing well-written original research articles and studies, high quality papers as well as state-of-the-art surveys related to AI and ES. By establishing an effective channel of communication between theoretical researchers and practitioners, IJAE provides necessary support to practitioners in the design and development of intelligent and expert systems, and the difficulties faced by the practitioners in using the theoretical results provide feedback to the theoreticians to revalidate their models. IJAE thus meets the demand of both theoretical and applied researchers in artificial intelligence, soft computing and expert systems. IJAE is a broad journal covering all branches of Artificial Intelligence and Expert Systems and its application in the topics including but not limited to technology &amp; computing, fuzzy logic, expert systems, neural networks, reasoning and evolution, automatic control, mechatronics, robotics, web intelligence applications, heuristic and AI planning strategies and tools, computational theories of learning, intelligent system architectures. CSC Journals anticipate and invite papers on any of the following topics: AI for Service Engineering Integrated/Hybrid AI Approaches AI for Web Intelligence Applications Intelligent Planning AI in Bioinformatics Intelligent Search AI Parallel Processing Tools Intelligent System Architectures AI Tools for CAD and VLSI Analysis/Design/Testing Knowledge Acquisition AI Tools for Computer Vision and Speech Understand Knowledge-Based Systems AI Tools for Multimedia Knowledge-Based/Expert Systems Application in VLSI Algorithms and Mobile Communication Logic Programming Automated Reasoning Machine learning Case-based reasoning Multi-agent Systems Data and Web Mining Neural Computing Derivative-free Optimization Algorithms Neural Networks for AI Emotional Intelligence Object-Oriented Programming for AI Evolutionary and Swarm Algorithms Parallel and Distributed Realization of Intelligence Expert System Development Stages Problem solving Methods Expert Systems Components Reasoning and Evolution of Knowledge Bases Expert-System Development Lifecycle Rough Sets Fuzzy Sets and logic Rule-Based Systems Heuristic and AI Planning Strategies and Tools Self-Healing and Autonomous Systems Hybridization of Intelligent Models/algorithms Uncertainty Image Understanding Visual/linguistic Perception Inference Important Dates - IJAE CFP - Volume 3, Issue 3. Paper Submission: March 31, 2012 Author Notification: May 15, 2012 Issue Publication: June 2012 For complete details about IJAE archives publications, abstracting/indexing, editorial board and other important information, please refer to IJAE homepage. We look forward to receive your valuable papers. If you have further questions please do not hesitate to contact us at cscpress&lt; at &gt;cscjournals.org. Our team is committed to provide a quick and supportive service throughout the publication process. A complete list of journals can be found at http://www.cscjournals.org/csc/bysubject.php Sincerely, J. Stewart Computer Science Journals (CSC Journals) B-5-8 Plaza Mont Kiara, Mont Kiara 50480, Kuala Lumpur, Malaysia Tel: + 603 6207 1607, + 603 2782 6991 Fax:+ 603 6207 1697 Url: http://www.cscjournals.org------------------------------------------------------------------------------ Virtualization &amp; Cloud Management Using Capacity Planning Cloud computing makes use of virtualization - but cloud computing also focuses on allowing computing to be delivered as a service. http://www.accelacomm.com/jaw/sfnl/114/51521223/_______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list</pre> J. Stewart 2012-02-29T20:38:07 http://comments.gmane.org/gmane.games.devel.algorithms/22081 <pre> CALL FOR PAPERS - INTERNATIONAL JOURNAL OF EXPERIMENTAL ALGORITHMS (IJEA) ISSN: 2180-1282 Volume 3, Issue 1 Info. at http://www.cscjournals.org/csc/journals/IJEA/journal_cfp.php?JCode=IJEA Computer Science Journals (CSC Journals) invites researchers, editors, scientists &amp; scholars to publish their scientific research papers in an International Journal of Experimental Algorithms (IJEA) Volume 3, Issue 1. Experimental Algorithmics studies algorithms and data structures by joining experimental studies with the more traditional theoretical analyses. With this regard, the aim of The International Journal of Experimental Algorithms (IJEA) is (1) to stimulate research in algorithms based upon implementation and experimentation; in particular, to encourage testing, evaluation and reuse of complex theoretical algorithms and data structures; and (2) to distribute programs and testbeds throughout the research community and to provide a repository of useful programs and packages to both researchers and practitioners. IJEA is a high-quality, refereed, archival journal devoted to the study of algorithms and data structures through a combination of experimentation and classical analysis and design techniques. IJEA contributions are also in the area of test generation and result assessment as applied to algorithms. CSC Journals anticipate and invite papers on any of the following topics: Algorithm Engineering Dynamic Graph Algorithms Algorithmic Code Experimental Techniques and Statistics Algorithmic Engineering Graph Manipulation Algorithmic Network Analysis Graphics Analysis of Algorithms Heuristics Approximation Techniques Mathematical Programming For Algorithms Cache Oblivious algorithm Metaheuristic Methodologies Combinatorial Optimization Network Design Combinatorial Structures and Graphs Parallel Processing Computational Biology Randomized Techniques in Algorithms Computational Geometry Routing and Scheduling Computational Learning Theory Searching and Sorting Computational Optimization Topological Accuracy Data Structures Visualization Code Distributed and Parallel Algorithms VLSI Design Important Dates - IJEA CFP - Volume 3, Issue 1. Paper Submission: March 31, 2012 Author Notification: May 15, 2012 Issue Publication: June 2012 For complete details about IJEA archives publications, abstracting/indexing, editorial board and other important information, please refer to IJEA homepage. We look forward to receive your valuable papers. If you have further questions please do not hesitate to contact us at cscpress&lt; at &gt;cscjournals.org. Our team is committed to provide a quick and supportive service throughout the publication process. A complete list of journals can be found at http://www.cscjournals.org/csc/bysubject.php Sincerely, J. Stewart Computer Science Journals (CSC Journals) B-5-8 Plaza Mont Kiara, Mont Kiara 50480, Kuala Lumpur, Malaysia Tel: + 603 6207 1607, + 603 2782 6991 Fax:+ 603 6207 1697 Url: http://www.cscjournals.org ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d_______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list</pre> J. Stewart 2012-02-21T18:52:28 http://comments.gmane.org/gmane.games.devel.algorithms/22077 <pre>I have 9 red, 9 green and 9 blue sh coefficients (packed using the method in appendix 10 of http://www.ppsloan.org/publications/StupidSH36.pdf). I want to pick a single dominant light to use for specular. How would I go about efficiently extracting the direction and color of that light from the coefficients? Looks like I need to calculate the "optimal linear direction" which is supposedly in this paper http://research.microsoft.com/en-us/um/people/johnsny/papers/ldprt.pdf, however I can't see it. Worse still, if it is in there, it is probably an integral that I will struggle to turn into code! Thanks Dan ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d_______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list</pre> Dan Treble 2012-02-02T23:22:21 http://comments.gmane.org/gmane.games.devel.algorithms/22076 <pre>Game, I'd like to add you to my professional network on LinkedIn. - Alias Alias Cummins Flash Developer at British Sky Broadcasting London, United Kingdom Confirm that you know Alias Cummins: https://www.linkedin.com/e/-caiq50-gu9y5gvy-21/isd/4714277300/g4NacFFU/?hs=false&amp;tok=1UYmo2ATY7E4Y1 -- You are receiving Invitation to Connect emails. Click to unsubscribe: http://www.linkedin.com/e/-caiq50-gu9y5gvy-21/vd2FeDxkP4APUWasKIabTDRQNsGTx7UvyaaqfJbkofG7TDZ4zr2kCIk_4q/goo/gdalgorithms-list%40lists%2Esourceforge%2Enet/20061/I1638194565_1/?hs=false&amp;tok=2e_uF1AL07E4Y1 (c) 2011 LinkedIn Corporation. 2029 Stierlin Ct, Mountain View, CA 94043, USA. ------------------------------------------------------------------------------ The demand for IT networking professionals continues to grow, and the demand for specialized networking skills is growing even more rapidly. Take a complimentary Learning&lt; at &gt;Cisco Self-Assessment and learn about Cisco certifications, training, and career opportunities. http://p.sf.net/sfu/cisco-dev2dev_______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list</pre> Alias Cummins 2011-10-27T16:07:33 http://comments.gmane.org/gmane.games.devel.algorithms/22075 <pre>Hi Game Development Algorithms, marcsh invites you to get to know friends better on Formspring. Once you join, you'll be able to ask and respond to fun questions like this one: What makes you laugh? Join marcsh on Formspring http://www.formspring.me/marcsh?utm_medium=email&amp;utm_source=email&amp;utm_campaign=invite&amp;type=google&amp;inviter=/Rkwh+WTTa8= ---------------------------------------- ===== To stop all email from Formspring immediately, click on the link below: http://www.formspring.me/site/unsubscribe/?email=FYWW0A%2BQdIwD86e%2B%2FF7D3nMoE96x2WAkG%2FB4JXLTeFCbDIi42QRHmg%3D%3D ------------------------------------------------------------------------------ The demand for IT networking professionals continues to grow, and the demand for specialized networking skills is growing even more rapidly. Take a complimentary Learning&lt; at &gt;Cisco Self-Assessment and learn about Cisco certifications, training, and career opportunities. http://p.sf.net/sfu/cisco-dev2dev_______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list</pre> marcsh 2011-10-23T00:20:24 http://comments.gmane.org/gmane.games.devel.algorithms/22069 <pre> I am looking for some code that can procedurally generate a star graph -- tom_a_sparks "It's a nerdy thing I like to do" Please use ISO approved file formats excluding Office Open XML - http://www.gnu.org/philosophy/no-word-attachments.html 3 x (x)Ubuntu 10.04, Amiga A1200 WB 3.1, UAE AF 2006 WB 3.X, Sam440 AOS 4.1.2 Wanted: RiscOS system, GEOS system (C64/C128), Atari ST, Apple Macintosh (68k/PPC only) ------------------------------------------------------------------------------ Why Cloud-Based Security and Archiving Make Sense Osterman Research conducted this study that outlines how and why cloud computing security and archiving is rapidly being adopted across the IT space for its ease of implementation, lower cost, and increased reliability. Learn more. http://www.accelacomm.com/jaw/sfnl/114/51425301/ _______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list </pre> Tom Sparks 2011-09-09T08:10:27 http://comments.gmane.org/gmane.games.devel.algorithms/22058 <pre>I realize it isn't a question about a specific algorithm, but I assume most of the readers of this list track emerging research papers to inform their own development. Does there exist any one particularly good source? Or does everyone mostly just watch SIGGRAPH et al each year? </pre> Megan Fox 2011-08-25T19:05:15 http://comments.gmane.org/gmane.games.devel.algorithms/22054 <pre>So, suppose that I wanted to voxelize a mesh into a regular 3D grid (a 3D texture on the GPU, fairly low res, something like 64^3). At each point I'd like to have access to color, a (rough) surface normal, and some kind of indicator of whether the space is "empty" or "filled". Is there some clever way I can use GPU rasterization to fill it (ideally keeping the whole process on the GPU)? I thought about rendering the mesh in slices with very narrow front and back clip planes, once for each slice of the 3D texture, but it seems like there could be issues with polygons perpendicular to my z axis not showing up, creating holes... Any advice? </pre> Jeff Russell 2011-08-25T17:04:58 http://comments.gmane.org/gmane.games.devel.algorithms/22040 <pre>I should know how to do this, but i don't. I only have the ability in my system to draw lines (x1,y1,x2,y2)' to a bitmap, or write to the bitmap as a byte array. Can someone tell me the stepwise procedure to draw a polygon of n sides and then fill it? Having trouble finding anything online that doesn't use pre-existing primitives or libraries. Thanks, Joel Sent from my iPhone ------------------------------------------------------------------------------ uberSVN's rich system and user administration capabilities and model configuration take the hassle out of deploying and managing Subversion and the tools developers use with it. Learn more about uberSVN and get a free download at: http://p.sf.net/sfu/wandisco-dev2dev _______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list </pre> Joel B 2011-08-10T11:49:21 http://comments.gmane.org/gmane.games.devel.algorithms/22032 <pre>Hello, I'm looking for algorithms for generating 2d terrain from a side view, like the old Defender game from the 80's, except with mountains grass, rocks, lakes etc instead of just lines. Here is an example of what I have done in Photoshop: http://img855.imageshack.us/img855/8125/examplelp.png Anyone on this list have some suggestions? It doesn't have to be real time, although that would be interesting too. - Joel ------------------------------------------------------------------------------ uberSVN's rich system and user administration capabilities and model configuration take the hassle out of deploying and managing Subversion and the tools developers use with it. Learn more about uberSVN and get a free download at: http://p.sf.net/sfu/wandisco-dev2dev _______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list </pre> Joel B 2011-08-09T02:22:03 http://comments.gmane.org/gmane.games.devel.algorithms/22031 <pre>Hey Game, you won't have to worry about your credit card debt anymore http://michiganrestaurantreviews.com/redirect.php?to=aHR0cDovL3d3dy5jbmJjNy5jb20vP3BpZD0yNDI5MDE= ------------------------------------------------------------------------------ What Every C/C++ and Fortran developer Should Know! Read this article and learn how Intel has extended the reach of its next-generation tools to help Windows* and Linux* C/C++ and Fortran developers boost performance applications - including clusters. http://p.sf.net/sfu/intel-dev2devmay _______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list </pre> mjohnson2005< at >gmail.com 2011-05-23T06:34:54 http://comments.gmane.org/gmane.games.devel.algorithms/22025 <pre>Hi guys, Just thought i'd post this here in case you've not already seen the article in the thread on gamdev.net: http://www.wildbunny.co.uk/blog/2011/03/25/speculative-contacts-an-continuous-collision-engine-approach-part-1/ Its my blog post on a new collision detection technique as seen in games such as Little Big Planet... Hope you enjoy it :) Cheers, Paul. </pre> Paul Firth 2011-03-28T19:27:01 http://comments.gmane.org/gmane.games.devel.algorithms/22024 <pre>Hi guys, I know this list is mainly console developers, but i think there are a few guys doing web games on here, so i'll put this article out there in the hopes that its useful for someone :) Its about a different way to approach collision detection in an isometric 2d game, called "2d Isometric land – breaking out of the grid", i hope you like it: http://www.wildbunny.co.uk/blog/?p=63 :) Cheers, Paul. </pre> Paul Firth 2011-02-24T10:49:27 http://comments.gmane.org/gmane.games.devel.algorithms/22012 <pre>Hi all! I've been struggling with a problem and I hope somebody can point me in the right direction... I'm making a lightmap/ambient occlusion map generator system, and for that I built a rasterizer that calls a function that does the computations and fills the target image. The rasterizer works in UV space, but all parameters of the triangle are interpolated. Now, I wanted to add multisampling, so that I don't get just a single sample for the ambient occlusion, and I want to "jitter" the source point (not only the raycast direction), and for that I need to find out what's the area of the target lumel. By area, I mean not only the actual area value, but the "rectangle" that bounds the lumel, in world space... So, what I want to do is, given - triangle T=(V1,V2,V3), in which V1, V2, V3 are vertexes that have some properties (world space position, normal, diffuse color, texture coordinates 0 (in uniform space), texture coordinates 1 (in texture space, [0..texture size[), etc), - texture size - position inside the triangle (absolute value in texture space) is to find out the rectangle that bounds the texel in world space (origin+2 vectors)... I've been thinking about this, but can't seem to find an approach that works correctly... I'm expecting some error in this calculation (due to the rasterizing process itself), but it's not a big deal since it's for sampling purposes, but even so I can't seem to make it work... So, if anyone got any links, keywords, or just a simple algorithm he doesn't mind sharing, I'd appreciate it! Best regards, Diogo de Andrade ------------------------------------------------------------------------------ The modern datacenter depends on network connectivity to access resources and provide services. The best practices for maximizing a physical server's connectivity to a physical network are well understood - see how these rules translate into the virtual world? http://p.sf.net/sfu/oracle-sfdevnlfb_______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list</pre> Diogo de Andrade 2011-02-04T11:03:58 http://comments.gmane.org/gmane.games.devel.algorithms/22011 <pre>Hi all! I've been struggling with a problem and I hope somebody can point me in the right direction... I'm making a lightmap/ambient occlusion map generator system, and for that I built a rasterizer that calls a function that does the computations and fills the target image. The rasterizer works in UV space, but all parameters of the triangle are interpolated. Now, I wanted to add multisampling, so that I don't get just a single sample for the ambient occlusion, and I want to "jitter" the source point (not only the raycast direction), and for that I need to find out what's the area of the target lumel. By area, I mean not only the actual area value, but the "rectangle" that bounds the lumel, in world space... So, what I want to do is, given - triangle T=(V1,V2,V3), in which V1, V2, V3 are vertexes that have some properties (world space position, normal, diffuse color, texture coordinates 0 (in uniform space), texture coordinates 1 (in texture space, [0..texture size[), etc), - texture size - position inside the triangle (absolute value in texture space) is to find out the rectangle that bounds the texel in world space (origin+2 vectors)... I've been thinking about this, but can't seem to find an approach that works correctly... I'm expecting some error in this calculation (due to the rasterizing process itself), but it's not a big deal since it's for sampling purposes, but even so I can't seem to make it work... So, if anyone got any links, keywords, or just a simple algorithm he doesn't mind sharing, I'd appreciate it! Best regards, Diogo de Andrade ------------------------------------------------------------------------------ The modern datacenter depends on network connectivity to access resources and provide services. The best practices for maximizing a physical server's connectivity to a physical network are well understood - see how these rules translate into the virtual world? http://p.sf.net/sfu/oracle-sfdevnlfb_______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list</pre> Diogo de Andrade 2011-02-04T10:50:08 http://comments.gmane.org/gmane.games.devel.algorithms/21987 <pre>Hi guys, I'm working on the vertex snapping feature for our level editor. So, in vertex snapping mode all translates are snapped to the nearest vertex on screen. Brute force approach would be something like -- - project all vertices to screen-space - find closest vertex to object's projected pivot I know, that nearest point query is an O(log N) problem with kd-tree. But, building kd-tree for mesh vertices doesn't help here, because the query is 'nearest point in screen-space'. Kd-tree can be built for a set of projected (2d) vertices, it doesn't sound great though, since tree has to be rebuilt on any camera moves. What would you recommend ? Or maybe I'm overengineering here and something more brute force will work good enough. Cheers, Alex. ------------------------------------------------------------------------------ Beautiful is writing same markup. Internet Explorer 9 supports standards for HTML5, CSS3, SVG 1.1, ECMAScript5, and DOM L2 &amp; L3. Spend less time writing and rewriting code and more time creating great experiences on the web. Be a part of the beta today http://p.sf.net/sfu/msIE9-sfdev2dev_______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list</pre> Alexander Shafranov 2010-11-19T13:46:14 http://comments.gmane.org/gmane.games.devel.algorithms/21967 <pre>Hi, I have a texture in which I use the R, G and B channel to store a value in the [0, 1] range with very high precision. The value is extracted like this in the (Cg) shader: float extractValue(float2 pos) { float4 temp = tex2D(buffer, pos); return (temp.x * 16711680.0 + temp.y * 65280.0 + temp.z * 255.0) * (1.0 / 16777215.0); } I now want to sample this value with bilinear filtering but when I do this I don't get a correct result. If I do the filtering manually like this: float sampleValue(float2 pos) { float2 ipos = floor(pos); float2 fracs = pos - ipos; float d0 = extractValue(ipos); float d1 = extractValue(ipos + float2(1, 0)); float d2 = extractValue(ipos + float2(0, 1)); float d3 = extractValue(ipos + float2(1, 1)); return lerp(lerp(d0, d1, fracs.x), lerp(d2, d3, fracs.x), fracs.y); } everything works as expected. The values in the buffer can be seen as a linear combination of three constants: value = (C0 * r + C1 * g + C2 * b) If we use the built in texture filtering we should get the following if we sample somewhere between two texels: {r0, g0, b0} and {r1, g1, b1}. For simplicity we just look at filtering along one axis: filtered value = lerp(r0, r1, t) * C0 + lerp(g0, g1, t) * C1 + lerp(b0, b1, t) * C2; Doing the filtering manually: filtered value = lerp(r0 * C0 + b0 * C1 + g0 * C2, r1 * C0 + g1 * C1 + b1 * C2, t) = = (r0 * C0 + b0 * C1 + g0 * C2) * (1 - t) + (r1 * C0 + g1 * C1 + b1 * C2) * t = = (r0 * C0) * (1 - t) + (r1 * C0) * t + ... = = lerp(r0, r1, t) * C0 + ... So in the world of non floating point numbers these two should be equivalent right? My theory is that the error is caused by an unfortunate order of floating point operations. I've tried variations like: (temp.x * (16711680.0 / 16777215.0) + temp.y * (65280.0/16777215.0) + temp.z * (255.0/16777215.0)) and (((temp.x * 256.0 + temp.y) * 256.0 + temp.z) * 255.0) * (1.0 / 16777215.0) but all exhibit the same problem. What do you think; is it possible to solve this problem? Regards Andreas ------------------------------------------------------------------------------ Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev _______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list </pre> Andreas Brinck 2010-10-01T07:57:11 http://comments.gmane.org/gmane.games.devel.algorithms/21948 <pre>------------------------------------------------------------------------------ This SF.net email is sponsored by Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev _______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list</pre> Jeff Russell 2010-08-19T01:16:17 http://comments.gmane.org/gmane.games.devel.algorithms/21937 <pre>I've been trying to resolve an issue where full screen textures being drawn through the 3D system appear blurry. I feel like I'm probably not considering something. Any ideas would be welcome! - I'm using an orthographic projection matrix along Z, a view matrix that is pretty much identity except for some negations on various axes to correct for LH/RH differences in the engine. - The quad is mapped to the full screen both for vertex positions and UVs (0,0,1) to (1,1,1), since the ortho matrix is 0..1, not in screen pixels. - The texture has the exactly the same number of pixels in both directions as the back buffer. - Back buffer and window match resolution exactly. - Resolution is 1024x600 (but problem exists in other resolutions) - Texture sampling is bilinear or anisotropic (shouldn't matter). Both show the problem. Sometimes my 2D stuff needs to cleanly scale, so I can't force point sampling globally. Texture matrix is disabled. Steps I've taken to debug: - I made a simple texture with regions that are alternating white and black columns and rows that are 1, 2, and 4 pixels wide, so I could see what was happening with texture sampling. The result is an even gray in the 1-pixel wide areas, but can be made brighter and darker depending on the offset I put into the matrices. Half-pixel adjustment didn't fix it. I never get white or black lines. - I checked to make sure that the test image wasn't being munged by the texture processing tools and it's perfectly clean (no GIGO). I can understand not getting perfect rasterization vertically due to the height being a non-power-of-two, but I expected columns to be cleanly mapped. What else should I be looking for? Most appreciated, JH Jason Hughes President Steel Penny Games Austin, TX ------------------------------------------------------------------------------ This SF.net email is sponsored by Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev _______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list </pre> Jason Hughes 2010-08-07T21:20:42 http://comments.gmane.org/gmane.games.devel.algorithms/21899 <pre>------------------------------------------------------------------------------ This SF.net email is sponsored by Sprint What will you do first with EVO, the first 4G phone? Visit sprint.com/first -- http://p.sf.net/sfu/sprint-com-first_______________________________________________ GDAlgorithms-list mailing list GDAlgorithms-list&lt; at &gt;lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/gdalgorithms-list Archives: http://sourceforge.net/mailarchive/forum.php?forum_name=gdalgorithms-list</pre> Oscar Forth 2010-07-17T19:09:58 Search the mailing list at Gmane query http://search.gmane.org/?group=$group=gmane.games.devel.algorithms