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      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.


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  1.     http://www.gamedev.net/topic/204055-calculating-reflection-vector-i-have-no-math-book-here/ Cheers, that's a lot simpler than reading this (at the bottom): http://www.gamasutra.com/view/feature/131424/pool_hall_lessons_fast_accurate_.php?page=3
  2. 1. If I subtract the last position from the current position position, would that vector be its current velocity?   2. If I used some trig to calculate the angle between the last and current position, would that satisfy the Alpha and Gamma?       1.1 Negating deformation, if the ball hits a surface with a CoR of say 0.9 and the ball has a CoR of say 0.92, will I use an average of the two, e.g. 0.91 * the velocity from 1?   2.1 Negating spin, if I have the approach angle relative to the normal of the surface, will the exiting angle be a reflection of this angle of incidence? (or was that just a drunken night playing pool and seeing double?)... and how to do using two vectors?
  3. So what is Gamma, Alpha and the velocity at any given time? I believe you've only rewritten the first part...   TBH, i've rewritten it in Lua so no vector3's...
  4. Hi, I've got an example from a book working, however the formulas are so densely packed i'm having trouble really understanding it. What i'm after is extracting the relevant information to extend the example and implementing a bounce. The book is here, and the sample code can be found on the right, i'm using the Cannon 2 example: http://shop.oreilly.com/product/9780596000066.do   Here's the DoSimulation function (it includes the preliminaries in each step for clarity) double cosX; double cosY; double cosZ; double xe, ze; double b, Lx, Ly, Lz; double tx1, tx2, ty1, ty2, tz1, tz2; // new local variablels: double sx1, vx1; double sy1, vy1; double sz1, vz1; // step to the next time in the simulation time+=tInc; // First calculate the direction cosines for the cannon orientation. // In a real game you would not want to put this calculation in this // function since it is a waste of CPU time to calculate these values // at each time step as they never change during the sim. I only put them here in // this case so you can see all the calculation steps in a single function. b = L * cos((90-Alpha) *3.14/180); // projection of barrel onto x-z plane Lx = b * cos(Gamma * 3.14/180); // x-component of barrel length Ly = L * cos(Alpha * 3.14/180); // y-component of barrel length Lz = b * sin(Gamma * 3.14/180); // z-component of barrel length cosX = Lx/L; cosY = Ly/L; cosZ = Lz/L; // These are the x and z coordinates of the very end of the cannon barrel // we'll use these as the initial x and z displacements xe = L * cos((90-Alpha) *3.14/180) * cos(Gamma * 3.14/180); ze = L * cos((90-Alpha) *3.14/180) * sin(Gamma * 3.14/180); // Now we can calculate the position vector at this time // Old position vector commented out: //s.i = Vm * cosX * time + xe; //s.j = (Yb + L * cos(Alpha*3.14/180)) + (Vm * cosY * time) - (0.5 * g * time * time); //s.k = Vm * cosZ * time + ze; // New position vector calc.: sx1 = xe; vx1 = Vm * cosX; sy1 = Yb + L * cos(Alpha * 3.14/180); vy1 = Vm * cosY; sz1 = ze; vz1 = Vm * cosZ; s.i = ( (m/Cd) * exp(-(Cd * time)/m) * ((-Cw * Vw * cos(GammaW * 3.14/180))/Cd - vx1) - (Cw * Vw * cos(GammaW * 3.14/180) * time) / Cd ) - ( (m/Cd) * ((-Cw * Vw * cos(GammaW * 3.14/180))/Cd - vx1) ) + sx1; s.j = sy1 + ( -(vy1 + (m * g)/Cd) * (m/Cd) * exp(-(Cd*time)/m) - (m * g * time) / Cd ) + ( (m/Cd) * (vy1 + (m * g)/Cd) ); s.k = ( (m/Cd) * exp(-(Cd * time)/m) * ((-Cw * Vw * sin(GammaW * 3.14/180))/Cd - vz1) - (Cw * Vw * sin(GammaW * 3.14/180) * time) / Cd ) - ( (m/Cd) * ((-Cw * Vw * sin(GammaW * 3.14/180))/Cd - vz1) ) + sz1; Idealy if someone could "name" descriptively sx1, sv1, ... sz1, sv1, (even though I have a good idea that these are the initial translation and initial velocity.)   These are the initial variables: Vm = 50; // m/s Alpha = 25; // degrees Gamma = 0; // along x-axis L = 12; // m Yb = 10; // on x-z plane tInc = 0.05; // seconds g = 9.8; // m/(s*s) // Initialize the new variables: m = 100; // kgs Vw = 10; // m/s GammaW = 90; // degrees Cw = 10; Cd = 30; I believe i'm after knowing Vm, Alpha and Gamma at the end (or probably at each step), and then how to use Alpha and Gamma to calculate the initial trajectory after the collision (say the collision plane is horizontal with its normal pointing straight up) (any CoR info would be useful too).   Many many thanks for any help ;)