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  • Why can't a blendShader sample anything but the current coordinate of the background image?

    - by Triynko
    In Flash, you can set a DisplayObject's blendShader property to a pixel shader (flash.shaders.Shader class). The mechanism is nice, because Flash automatically provides your Shader with two input images, including the background surface and the foreground display object's bitmap. The problem is that at runtime, the shader doesn't allow you to sample the background anywhere but under the current output coordinate. If you try to sample other coordinates, it just returns the color of the current coordinate instead, ignoring the coordinates you specified. This seems to occur only at runtime, because it works properly in the Pixel Bender toolkit. This limitation makes it impossible to simulate, for example, the Aero Glass effect in Windows Vista/7, because you cannot sample the background properly for blurring. I must mention that it is possible to create the effect in Flash through manual composition techniques, but it's hard to determine when it actually needs updated, because Flash does not provide information about when a particular area of the screen or a particular display object needs re-rendered. For example, you may have a fixed glass surface with objects moving underneath it that don't dispatch events when they move. The only alternative is to re-render the glass bar every frame, which is inefficient, which is why I am trying to do it through a blendShader so Flash determines when it needs rendered automatically. Is there a technical reason for this limitation, or is it an oversight of some sort? Does anyone know of a workaround, or a way I could provide my manual composition implementation with information about when it needs re-rendered? The limitation is mentioned with no explanation in the last note in this page: http://help.adobe.com/en_US/as3/dev/WSB19E965E-CCD2-4174-8077-8E5D0141A4A8.html It says: "Note: When a Pixel Bender shader program is run as a blend in Flash Player or AIR, the sampling and outCoord() functions behave differently than in other contexts.In a blend, a sampling function will always return the current pixel being evaluated by the shader. You cannot, for example, use add an offset to outCoord() in order to sample a neighboring pixel. Likewise, if you use the outCoord() function outside a sampling function, its coordinates always evaluate to 0. You cannot, for example, use the position of a pixel to influence how the blended images are combined."

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  • Collision detection with entities/AI

    - by James Williams
    I'm making my first game in Java, a top down 2D RPG. I've handled basic collision detection, rendering and have added an NPC, but I'm stuck on how to handle interaction between the player and the NPC. Currently I'm drawing out my level and then drawing characters, NPCs and animated tiles on top of this. The problem is keeping track of the NPCs so that my Character class can interact with methods in the NPC classes on collision. I'm not sure my method of drawing the level and drawing everything else on top is a good one - can anyone shed any light on this topic?

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  • Floodfill algorithm for GO

    - by user1048606
    The floodfill algorithm is used in the bucket tool in MS paint and photoshop, but it can also be used for GO and minesweeper. http://en.wikipedia.org/wiki/Flood_fill In go you can capture groups of stones, this website portrays it with two stones. http://www.connectedglobe.com/mindy/cap6.html This is my floodfill method in Java, it is not capturing a group of stones and I have no idea why because to me it makes sense. public void floodfill(int turn, int col, int row){ for(int a = col; a<19; a++){ for(int b = row; b<19; b++){ if(turn == black){ if(stones[col][row] == white){ stones[col][row] = 0; floodfill(black, col-1, row); floodfill(black, col+1, row); floodfill(black, col, row-1); floodfill(black, col, row+1); } } } } } It searches up, down, left, right for all the stones on the board. If the stones are white it captures them by making them 0, which represents empty.

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  • OpenGL ES rotate texture

    - by 0xSina
    I just got started with OpenGL ES... I have a fragment: const char * sFragment = _STRINGIFY( varying highp vec2 coordinate; precision mediump float; uniform vec4 maskC; uniform float threshold; uniform sampler2D videoframe; uniform sampler2D videosprite; uniform vec4 mask; uniform vec4 maskB; uniform int recording; vec3 normalize(vec3 color, float meanr) { return color*vec3(0.75 + meanr, 1., 1. - meanr); } void main() { float d; float dB; float dC; float meanr; float meanrB; float meanrC; float minD; vec4 pixelColor; vec4 spriteColor; pixelColor = texture2D(videoframe, coordinate); spriteColor = texture2D(videosprite, coordinate); meanr = (pixelColor.r + mask.r)/8.; meanrB = (pixelColor.r + maskB.r)/8.; meanrC = (pixelColor.r + maskC.r)/8.; d = distance(normalize(pixelColor.rgb, meanr), normalize(mask.rgb, meanr)); dB = distance(normalize(pixelColor.rgb, meanrB), normalize(maskB.rgb, meanrB)); dC = distance(normalize(pixelColor.rgb, meanrC), normalize(maskC.rgb, meanrC)); minD = min(d, dB); minD = min(minD, dC); gl_FragColor = spriteColor; if (minD > threshold) { gl_FragColor = pixelColor; } } Now, depending on wether recording is 0 or 1, I want to rotate uniform sampler2D videosprite 180 degrees (reflection in x-axis, flip vertically). How can I do that? I found the function glRotatef(), but how do i specify that I want to rotate video sprite and not videoframe? Thanks

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  • New to CG shader programming, what program should I use to write and test them?

    - by Notbad
    I have started witting some shaders. First ones were fairly easy to write in notepad but now I need something with a bit more meat. I have checked rendermonnkey that seems to support CG but it is really old and don't know if it is a good option. On the other hand there exist this FX Composer 2.0 but it seems somthing that could really distract me from learning shaders because it seems a pretty deep program. Are there any other possibilities? There's a really nice alternative to write shaders named ShaderToy but just supports GLSL. Any information will be really welcomed. Thanks in advance.

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  • Procedural terrains in 3D: what has been done ? Are there common algo and/or theories about it ?

    - by jokoon
    Besides programming, modeling an environment takes a great deal of time. I don't know about the work time involved, for example, in a WoW dungeon level, or other beautiful city-like, future environment, jungles, fantasy, etc, but this kind of work is made from scratch by artists. What are the techniques involved in the TorchLight level randomizer, and does other titles have similarities with this ? Is there a family name for such techniques ?

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  • Unity3D Android : Game Over/Retry

    - by user3666251
    Im making a simple 2D game for android using the Unity3D game engine.I created all the levels and everything but Im stuck at making the game over/retry menu.So far I've been using new scenes as a game over menu.I used this simple script : pragma strict var level = Application.LoadLevel; function OnCollisionEnter(Collision : Collision) { if(Collision.collider.tag == "Player") { Application.LoadLevel("GameOver"); } } And this as a 'menu' : #pragma strict var myGUISkin : GUISkin; var btnTexture : Texture; function OnGUI() { GUI.skin = myGUISkin; if (GUI.Button(Rect(Screen.width/2-60,Screen.height/2+30,100,40),"Retry")) Application.LoadLevel("Easy1"); if (GUI.Button(Rect(Screen.width/2-90,Screen.height/2+100,170,40),"Main Menu")) Application.LoadLevel("MainMenu"); } The problem stands at the part where I have to create over 200 game over scenes,obscales(the objects that kill the player) and recreate the same script over 200 times for each level. Is there any other way to make this faster and less painful? I've been searching the web but didn't find anything useful according to my issue. Thank you.

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  • Dynamic Quad/Oct Trees

    - by KKlouzal
    I've recently discovered the power of Quadtrees and Octrees and their role in culling/LOD applications, however I've been pondering on the implementations for a Dynamic Quad/Oct Tree. Such tree would not require a complete rebuild when some of the underlying data changes (Vertex Data). Would it be possible to create such a tree? What would that look like? Could someone point me in the correct direction to get started? The application here would, in my scenario, be used for a dynamically changing spherical landscape with over 10,000,000 verticies. The use of Quad/Oct Trees is obvious for Culling & LOD as well as the benefits from not having to completely recompute the tree when the underlying data changes.

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  • Using Behavior Trees and Events together

    - by weichsem
    I am beginning to work with behavior trees and am unsure how events should be handled within the tree. Lets say we have a space game where the player is dogfighting with a handful of other ships, some friendly some not. The player destroys a ship and the rest of the hostile ships should then start to retreat. How was should the shipWasDestroyed event effect the other ship's behavior trees so that they start running the retreat behavior? One way I could think of doing this is have all the conditions I care about be high level nodes that effectively state change the ship. This would mean I'd have to check all of these state change conditions on every frame the behavior tree was run, even if they are very rare occurrences. I'd prefer not doing this for performance and complexity reasons. From looking at the Halo papers on behavior trees it seems that they handled this by dynamically placing nodes into the tree when the event occurred. It seems like calculating where the new node should go could be problematic depending on the current state of the running behavior. How is this normally handled?

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  • Generating grammatically correct MUD-style attack descriptions

    - by Extrakun
    I am currently working on a text based game, where the outcome of a combat round goes something like this %attacker% inflicts a serious wound (12 points damage) on %defender% Right now, I just swap %attacker% with the name of the attacker, and %defender% for the name of the defender. However, the description works, but don't read correctly. Since the game is just all text, I don't want to resort to generic descriptions (Such as "You use Attack on Goblin for 5 damage", which arguably solve the problem) How do I generate correct descriptions for cases where %attacker% refers to "You", the player? "You inflicts..." is wrong "Bees", or other plural? I need somehow to know I should prefix the name with a "The " If %attacker% is a generic noun, such as "Goblin", it will read weird as opposed to %attacker% being a name. Compare "Goblin inflicts..." vs. "Aldraic Swordbringer inflicts...." How does text-based games usually resolve such issues?

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  • Changing balls direction in Pong

    - by hustlerinc
    I'm making a Pong game to get started with game-developement but I've run into a problem that i can't figure out. When trying to change the balls direction it doesn't change. This is the relevant code: function moveBall(){ this.speed = 2.5; this.direction = 2; if(this.direction == 1){ ball.X +=this.speed; } else if(this.direction == 2){ ball.X -=this.speed; } } function collision(){ if(ball.X == 500){ moveBall.direction = 2; } if(ball.X == 300){ moveBall.direction = 1; } } Why doesn't it work? I've tried many different ways, and none of them seem to work. The moveBall.direction changes though, since it alerts the new direction once it reaches the defined ball.X position. If someone could help me I would deeply appreciate it. I've included a JSFiddle link. http://jsfiddle.net/hustlerinc/y4wp3/

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  • Velocity collision detection (2D)

    - by ultifinitus
    Alright, so I have made a simple game engine (see youtube) And my current implementation of collision resolution has a slight problem, involving the velocity of a platform. Basically I run through all of the objects necessary to detect collisions on and resolve those collisions as I find them. Part of that resolution is setting the player's velocity = the platform's velocity. Which works great! Unless I have a row of platforms moving at different velocities or a platform between a stack of tiles.... (current system) bool player::handle_collisions() { collisions tcol; bool did_handle = false; bool thisObjectHandle = false; for (int temp = 0; temp < collideQueue.size(); temp++) { thisObjectHandle = false; tcol = get_collision(prevPos.x,y,get_img()->get_width(),get_img()->get_height(), collideQueue[temp]->get_position().x,collideQueue[temp]->get_position().y, collideQueue[temp]->get_img()->get_width(),collideQueue[temp]->get_img()->get_height()); if (prevPos.y >= collideQueue[temp]->get_prev_pos().y + collideQueue[temp]->get_img()->get_height()) if (tcol.top > 0) { add_pos(0,tcol.top); set_vel(get_vel().x,collideQueue[temp]->get_vel().y); thisObjectHandle = did_handle = true; } if (prevPos.y + get_img()->get_height() <= collideQueue[temp]->get_prev_pos().y) if (tcol.bottom > 0) { add_pos(collideQueue[temp]->get_vel().x,-tcol.bottom); set_vel(get_vel().x/*collideQueue[temp]->get_vel().x*/,collideQueue[temp]->get_vel().y); ableToJump = true; jumpTimes = maxjumpable; thisObjectHandle = did_handle = true; } /// /// ADD CODE FROM NEXT CODE BLOCK HERE (on forum, not in code) /// } for (int temp = 0; temp < collideQueue.size(); temp++) { thisObjectHandle = false; tcol = get_collision(x,y,get_img()->get_width(),get_img()->get_height(), collideQueue[temp]->get_position().x,collideQueue[temp]->get_position().y, collideQueue[temp]->get_img()->get_width(),collideQueue[temp]->get_img()->get_height()); if (prevPos.x + get_img()->get_width() <= collideQueue[temp]->get_prev_pos().x) if (tcol.left > 0) { add_pos(-tcol.left,0); set_vel(collideQueue[temp]->get_vel().x,get_vel().y); thisObjectHandle = did_handle = true; } if (prevPos.x >= collideQueue[temp]->get_prev_pos().x + collideQueue[temp]->get_img()->get_width()) if (tcol.right > 0) { add_pos(tcol.right,0); set_vel(collideQueue[temp]->get_vel().x,get_vel().y); thisObjectHandle = did_handle = true; } } return did_handle; } (if I add the following code {where the comment to do so is}, which is glitchy, the above problem doesn't happen, though it brings others) if (!thisObjectHandle) { if (tcol.bottom > tcol.top) { add_pos(collideQueue[temp]->get_vel().x,-tcol.bottom); set_vel(get_vel().x,collideQueue[temp]->get_vel().y); } else if (tcol.top > tcol.bottom) { add_pos(0,tcol.top); set_vel(get_vel().x,collideQueue[temp]->get_vel().y); } } How would you change my system to prevent this?

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  • how to transform child elements position into a world position

    - by MrGreg
    So Im making a 2d space game and I have a bunch of spaceships that have turrets. Objects have a position and orientation, the ships being in world coordinates while the turrets are children and coordinates are relative to their parents. How do I efficiently calculate the position of a turret in world coordinates (i.e. when it fires and I need to know where to place a bullet in the world)? Calculating the turrets orientation is trivial - I just add the turrets relative angle to its parents. For position though, I guess I could do a bunch of trigonometry but this MUST be a common problem with a good/fast general solution? Should I be relearning how to do matrix math again? :) btw - Im creating the game in javascript+canvas but its the math/algorithm im interested in here Cheers, Greg

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  • Actor and Sprite, who should own these properties?

    - by Gerardo Marset
    I'm writing sort of a 2D game engine for making the process of creating games easier. It has two classes, Actor and Sprite. Actor is used for interactive elements (the player, enemies, bullets, a menu, an invisible instance that controls score, etc) and Sprite is used for animated (or not) images with transparency (or not). The actor may have an assigned sprite that represents it on the screen, which may change during the game. E.g. in a top-down action game you may have an actor with a sprite of a little guy that changes when attacking, walking, and facing different directions, etc. Currently the actor has x and y properties (its coordinates in the screen), while the sprite has an index property (the number of the frame currently being shown by the sprite). Since the sprite doesn't know which actor it belongs to (or if it belongs to an actor at all), the actor must pass its x and y coordinates when drawing the sprite. Also, since a actors may reset its sprite each frame (and usually do), the sprite's index property must be passed from the old to the new sprite like so (pseudocode): function change_sprite(new_sprite) old_index = my.sprite.index my.sprite = new_sprite() my.sprite.index = old_index % my.sprite.frames end I always thought this was kind of cumbersome, but it never was a big problem. Now I decided to add support for more properties. Namely a property to draw the sprite rotated, a property to draw it flipped, it a property draw it stretched, etc. These should probably belong to the sprite and not the actor, but if they do, the actor would have to pass them from the old to the new sprite each time it changes... On the other hand, if they belonged to the actor, the actor would have to pass each property to the sprite when drawing it (since the sprite doesn't know which actor it belongs to, and it shouldn't, since sprites aren't just meant to be used by actors, really). Another option I thought of would be having an extra class that owns all these properties (plus index, x and y) and links an actor with a sprite, but that doesn't come without drawbacks. So, what should I do with all these properties? Thanks!

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  • Why does my model render differently than its preview?

    - by Raven Dreamer
    I've been importing .fbx files that I made with 3DS Max 2012 into Unity, and it's quite neat to see my models running around in game. However, I can't help but notice that the models, as they're rendered in game, vary substantially from what they look like in the preview (and also what they looked like in 3DS Max). Observe: In-Game Unity Preview 3DS Max My gut tells me that I'm not setting up Unity's lighting system properly. What, then, do I need to do, to either my scene or my model, in order to get the left-most picture to look like the middle one?

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  • backface culling error (in world space)

    - by acrilige
    I write simple software renderer. In my pipeline i have stage of backface culling. But looks like it has some error (see picture). I perform culling right after world transformation (is it correct?). (i can't insert picture in post coz i don't have enough points, so i just upload it (cube model): http://imageshack.us/photo/my-images/705/bcerror.png/) Vector3F view_dir(0.0f, 0.0f, 1.0f); std::vector<Triangle> to_remove; for (Triangle &t : m_triangles) { Vector4F e1 = t.v2 - t.v1; Vector4F e2 = t.v3 - t.v1; Vector3F normal( e1.y * e2.z - e1.z * e2.y, e1.z * e2.x - e1.x * e2.z, e1.x * e2.y - e1.y * e2.x ); normal.Normalize(); float dot = Dot(view_dir, normal); if (dot <= 0) to_remove.push_back(t); } for (Triangle& t : to_remove) m_triangles.erase(std::remove(m_triangles.begin(), m_triangles.end(), t), m_triangles.end()); Camera sits in origin and points in screen (RH). What is the reason? For better explanation i upload picture with cube rotation screenshots: http://imageshack.us/photo/my-images/842/bcmove.png/ UPDATED: The error occurs only when triangle has non-zero offset from origin UPDATED 2: If i process backface culling in clip space (after transforming all vertices with view and projection matrix), and just check z coordinate of triangle normal - it works perfect... Can i perform culing RIGHT BEFORE view/proj transforms? In this case looks like culling will not depends of projection and it's not right?.. UPDATED 3: I found answer and will post it in two hours - again coz of reputation lack.

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  • How to implement a game launch counter in LibGDX

    - by Vishal Kumar
    I'm writing a game using LibGDX in which I want to save the number of launches of a game in a text file. So, In the create() of my starter class, I have the following code ..but it's not working public class MainStarter extends Game { private int count; @Override public void create() { // Set up the application AppSettings.setUp(); if(SettingsManager.isFirstLaunch()){ SettingsManager.createTextFileInLocalStorage("gamedata"); SettingsManager.writeLine("gamedata", "Launched:"+count ,FileType.LOCAL_FILE ); } else{ SettingsManager.writeLine("gamedata", "Not First launch :"+count++ ,FileType.LOCAL_FILE ); } // // Load assets before setting the screen // ##################################### Assets.loadAll(); // Set the tests screen setScreen(new MainMenuScreen(this, "Main Menu")); } } What is the proper way to do this?

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  • Checking whether a specific key was pressed in enchantJS

    - by MxyL
    I am using enchantJS and would like to use the letters and numbers as well as numpad on a keyboard to do different things (eg: hotkeys). From this page http://users.csc.calpoly.edu/~foaad/enchant/guide/playerInput.html By default, enchant.js provides input listeners for six buttons: UP, DOWN, LEFT, RIGHT, A, and B. By default, the directions are bound to the arrow keys. Any of the six buttons may also be bound to any key with an ASCII value. We’ll address that later. So enchant provides the ability to bind keys to different input such as up, down, left, right...but how can I simply check whether the D or X key was pressed, and if so, perform certain actions based on that event?

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  • Stop a rotating object at a specified angle?

    - by Krummelz
    I'm working in JavaScript with HTML5 and the canvas. I have an object which is rotating at a certain speed, and I need the object's rotation to slow down gradually and the front of the object to stop at a specified angle. (I'm using radians, not degrees.) I have a variable to keep track of the angle which the object is facing, as it rotates. How would I go about getting the object to come to rest, facing the direction I want it to?

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  • Complete Guide/Tutorials on LWJGL?

    - by user43353
    Dont get me wrong, I finished these tutorials on http://lwjgl.org/wiki/index.php?title=Main_Page. I finished The Basics section, OpenGL 3.2 and newer section, and I looked at the Example Code section. They were great tutorials, and I have looked at the external tutorials as well. I don't know where to go from here, and OpenGL is not my strong point. Some one suggested Learning Modern 3D Graphics Programming, and I didnt learn much. I looked at the port to LWJGL, but the book was on C and I couldn't really understand what the OpenGL meant. I am trying to learn 2D gaming, not 3D. Maybe later. Is there any tutorials that aren't C/C++ heavy and teach you 2D OpenGL?

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  • Moving a Cube from a GUI texture on iOS [on hold]

    - by London2423
    I really hope someone can help me in this since I am working already two days but without any result. What I' am trying to achieve in this instance is to move a GameObject when a GUI Texture is touch on a Iphone. The GameObject to be moved is named Cube. The Cube has a Script named "Left" that supposedly when is "call it " from the GUITexture the Cube should move left. I hope is clear: I want to "activated" the script in the Game Object from the Guitexture. I try to use send message but without any joy as well so I am using GetComponent. This is the script "inside" the GUITexture using Unity and C# //script inside the gameobject cube so it can move left when call it from the GUItexture void Awake() { left = Cube.GetComponent<Left>().enable = true; } void Start() { Cube = GameObject.Find ("Cube"); } void Update () { //loop through all the touches on the screeen for(int i = 0 ; i < Input.touchCount; i++) { //execute this code for current touch (i) on the screen if(this.guiTexture.HitTest(Input.GetTouch(i).position)) { //if current hits our guiTecture, run this code if(Input.GetTouch (i).phase == TouchPhase.Began) //move the cube object Cube.GetComponent<Left> (); } if(Input.GetTouch (i).phase == TouchPhase.Ended) { return; } if(Input.GetTouch(i).phase == TouchPhase.Stationary); //if current finger is stationary run this code { Cube.GetComponent<Left> (); } } } } } This is the script inside the GameObject named "Cube" that is activated from the Gui Texture and when is activated from the GUITexture should allow the cube to move left public class Left : MonoBehaviour { // Use this for initialization void Start () { } // Update is called once per frame void OnMousedown () { transform.position += Vector3.left * Time.deltaTime; } } Before write here I search all documentation, tutorial videos, forums but I still don't understand where is my mistake. May please someone help me Thanks CL

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  • How do I stop stretching during window re-size in XNA?

    - by Bradley Uffner
    In my windowed mode XNA game when the user resizes the window the game stops updating the window and the last frame drawn is stretched and distorted until the user releases the mouse and the resize completes. Is there any way to have the game continue to run "normally", updating frames and redrawing the screen, during the resize event? I realize that keeping the render loop going while resizing may not be possible or recommended due do hardware managed resources getting continually created and destroyed, but is there any way to stop the ugly stretching? Ideally by leaving the existing frame unscaled in the top left, or with a black screen if that isn't possible.

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  • Physics-based dynamic audio generation in games

    - by alexc
    I wonder if it is possible to generate audio dynamically without any (!) audio assets, using pure mathematics/physics and some input values like material properties and spatial distribution of content in scene space. What I have in mind is something like a scene, with concrete floor, wooden table and glass on it. Now let's assume force pushes the glass towards the edge of table and then the glass falls onto the floor and shatters. The near-realistic glass destruction itself would be possible using voxels and good physics engine, but what about the sound the glass makes while shattering? I believe there is a way to generate that sound, because physics of sound is fairly known these days, but how computationaly costy that would be? Consumer hardware or supercomputers? Do any of you know some good resources/videos of such an experiment?

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  • (Abstract) Game engine design

    - by lukeluke
    I am writing a simple 2D game (for mobile platforms) for the first time. From an abstract point of view, i have the main player controlled by the human, the enemies, elments that will interact with the main player, other living elements that will be controlled by a simple AI (both enemies and non-enemies). The human player will be totally controlled by the player, the other actors will be controlled by AI. So i have a class CActor and a class CActorLogic to start with. I would define a CActor subclass CHero (the main player controlled with some input device). This class will probably implement some type of listener, in order to capture input events. The other players controlled by the AI will be probably a specific subclass of CActor (a subclass per-type, obviously). This seems to be reasonable. The CActor class should have a reference to a method of CActorLogic, that we will call something like CActorLogic::Advance() or similar. Actors should have a visual representation. I would introduce a CActorRepresentation class, with a method like Render() that will draw the actor (that is, the right frame of the right animation). Where to change the animation? Well, the actor logic method Advance() should take care of checking collisions and other things. I would like to discuss the design of a game engine (actors, entities, objects, messages, input handling, visualization of object states (that is, rendering, sound output and so on)) but not from a low level point of view, but from an high level point of view, like i have described above. My question is: is there any book/on line resource that will help me organize things (using an object oriented approach)? Thanks

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  • Adding tolerance to a point in polygon test

    - by David Gouveia
    I've been using this method which was taken from Game Coding Complete to detect whether a point is inside of a polygon. It works in almost every case, but is failing on a few edge cases, and I can't figure out the reason. For example, given a polygon with vertices at (0,0) (0,100) and (100,100), the algorithm is returning: True for any point strictly inside the polygon False for any of the vertices False for (0, 50) which lies on one of the edges of the polygon True (?) for (50,50) which is also on one of the edges of the polygon I'd actually like to relax the algorithm so that it returns true in all of these cases. In other words, it should return true for points that are strictly inside, for the vertices themselves, and for points on the edges of the polygon. If possible I'd also like to give it enough tolerance so that it always tend towards "true" in face of floating point fluctuations. For example, I have another method, that given a line segment and a point, returns the closest location on the line segment to the given point. Currently, given any point outside the polygon and one of its edges, there are cases where the result is categorized as being inside by the method above, while other points are considered outside. I'd like to give it enough tolerance so that it always returns true in this situation. The way I've currently solved the problem is an hack, which consists of using an external library to inflate the polygon by a few pixels, and performing the tests on the inflated polygon, but I'd really like to replace this with a proper solution.

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