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  • JMonkeyEngine display a spatial in a Nifty GUI interface

    - by Yanick Rochon
    I want to display a spatial (or the rendering of a spatial/scene) in my HUD interface. I'm really not sure how to go with this. I have search the documentation, but all the queries I search yields no result, and all I could find about images is that one can specify one with the setBackgroundImage method in the builder and setImage from the ImageRenderer class. The latter takes a String or a NiftyImage, but I'm not sure how to create one without loading an image file. Any help to understand this (if even possible) is appreciated. Thanks!

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  • Writing to a D3DFMT_R32F render target clamps to 1

    - by Mike
    I'm currently implementing a picking system. I render some objects in a frame buffer, which has a render target, which has the D3DFMT_R32F format. For each mesh, I set an integer constant evaluator, which is its material index. My shader is simple: I output the position of each vertex, and for each pixel, I cast the material index in float, and assign this value to the Red channel: int ObjectIndex; float4x4 WvpXf : WorldViewProjection< string UIWidget = "None"; >; struct VS_INPUT { float3 Position : POSITION; }; struct VS_OUTPUT { float4 Position : POSITION; }; struct PS_OUTPUT { float4 Color : COLOR0; }; VS_OUTPUT VSMain( const VS_INPUT input ) { VS_OUTPUT output = (VS_OUTPUT)0; output.Position = mul( float4(input.Position, 1), WvpXf ); return output; } PS_OUTPUT PSMain( const VS_OUTPUT input, in float2 vpos : VPOS ) { PS_OUTPUT output = (PS_OUTPUT)0; output.Color.r = float( ObjectIndex ); output.Color.gba = 0.0f; return output; } technique Default { pass P0 { VertexShader = compile vs_3_0 VSMain(); PixelShader = compile ps_3_0 PSMain(); } } The problem I have, is that somehow, the values written in the render target are clamped between 0.0f and 1.0f. I've tried to change the rendertarget format, but I always get clamped values... I don't know what the root of the problem is. For information, I have a depth render target attached to the frame buffer. I disabled the blend in the render state the stencil is disabled Any ideas?

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  • How do I draw a single Triangle with XNA and fill it with a Texture?

    - by Deukalion
    I'm trying to wrap my head around: http://msdn.microsoft.com/en-us/library/bb196409.aspx I'm trying to create a method in XNA that renders a single Triangle, then later make a method that takes a list of Triangles and renders them also. But it isn't working. I'm not understanding what all the things does and there's not enough information. My methods: // Triangle is a struct with A, B, C (didn't include) A, B, C = Vector3 public static void Render(GraphicsDevice device, List<Triangle> triangles, Texture2D texture) { foreach (Triangle triangle in triangles) { Render(device, triangle, texture); } } public static void Render(GraphicsDevice device, Triangle triangle, Texture2D texture) { BasicEffect _effect = new BasicEffect(device); _effect.Texture = texture; _effect.VertexColorEnabled = true; VertexPositionColor[] _vertices = new VertexPositionColor[3]; _vertices[0].Position = triangle.A; _vertices[1].Position = triangle.B; _vertices[2].Position = triangle.B; foreach (var pass in _effect.CurrentTechnique.Passes) { pass.Apply(); device.DrawUserIndexedPrimitives<VertexPositionColor> ( PrimitiveType.TriangleList, _vertices, 0, _vertices.Length, new int[] { 0, 1, 2 }, // example has something similiar, no idea what this is 0, 3 // 3 = gives me an error, 1 = works but no results ); } }

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  • How can I cull non-visible isometric tiles?

    - by james
    I have a problem which I am struggling to solve. I have a large map of around 100x100 tiles which form an isometric map. The user is able to move the map around by dragging the mouse. I am trying to optimize my game only to draw the visible tiles. So far my code is like this. It appears to be ok in the x direction, but as soon as one tile goes completely above the top of the screen, the entire column disappears. I am not sure how to detect that all of the tiles in a particular column are outside the visible region. double maxTilesX = widthOfScreen/ halfTileWidth + 4; double maxTilesY = heightOfScreen/ halfTileHeight + 4; int rowStart = Math.max(0,( -xOffset / halfTileWidth)) ; int colStart = Math.max(0,( -yOffset / halfTileHeight)); rowEnd = (int) Math.min(mapSize, rowStart + maxTilesX); colEnd = (int) Math.min(mapSize, colStart + maxTilesY); EDIT - I think I have solved my problem, but perhaps not in a very efficient way. I have taken the center of the screen coordinates, determined which tile this corresponds to by converting the coordinates into cartesian format. I then update the entire box around the screen.

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  • Novice prototyping a massive multiplayer webpage based gaming system

    - by Sean Hendlin
    I'm trying to build a website based game in which various pages of the site act as different areas of the game. I am wondering what you would recommended as a design structure. Which languages would be best if building what will hopefully becomes a massive system able to scale to massive amounts of users. I am wondering if and how various elements from differing languages could be meshed to interact with each other. For example could I use html5, javascript, and PHP? What about asp.net how might that factor in? I'm a newbie programmer but I've been working on this idea for years and I want to build it to reality. Your comments and suggestions are appreciated. P.S.: The game is not all graphics and animation (though flash like appearance and some animation would be nice). What I am thinking of is essentially a heavily gamified system of forms. And LOTS of data in many different categories cross referencing each-other. I'm not sure how to go about structuring the collection of data. Also while I know javascript can be used to process some functions, I'm wondering what sort of base system I would need to handle the server side processing of what I am expecting to be some pretty significant algorithm processing. That is to say I expect to have many many many functions and I'm not sure how to mange this using javascript. I feel like they would be forgotten, mixed up, disorganizes as they essentially only exist where they are coded. I guess I need to learn something of libraries? OK, Thank you! Is enough from me for now.

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  • Is there any simple game that involves psychological factors?

    - by Roman
    I need to find a simple game in which several people need to interact with each other. The game should be simple for an analysis (it should be simple to describe what happens in the game, what players did). Because of the last reason, the video games are not appropriate for my purposes. I am thinking of a simple, schematic, strategic game where people can make a limited set of simple moves. Moreover, the moves of the game should be conditioned not only by a pure logic (like in chess or go). The behavior in the game should depend on psychological factors, on relations between people. In more details, I think it should be a cooperation game where people make their decisions based on mutual trust. It would be nice if players can express punishment and forgiveness in the game. Does anybody knows a game that is close to what I have described above? ADDED I need to add that I need a game where actions of players are simple and easy to formalize. Because of that I cannot use verbal games (where communication between players is important). By simple actions I understand, for example, moves on the board from one position to another one, or passing chips from one player to another one and so on.

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  • Using copyrighted sprites

    - by Zertalx
    I was thinking about making a pacman clone, I know there is a similar question here Using Copyrighted Images , but I know i can't use the original art from the game because it belongs to Namco, so if I design a character that has the shape of the slice circle it will look exactly like pacman, maybe if I use green instead of yellow? Also if the game plays like the original pacman, it is wrong? I just want to make the game as a personal project and and publish it in my site without getting in trouble

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  • Group Matchmaking

    - by Simon Kérouack
    Consider different groups(1 or more players) queuing together, we want to make 2 opposing teams containing each the same amount of players while keeping the groups together. At the same time we want to make both teams' average ranking as close as possible. Now also consider we have as a working set the subset of groups currently queuing within a given ranking range. For an example, let's say we have the following groups, ordered by queuing time: Id, playerCount, totalRank, avgRank 0, 3, 126, 42 1, 2, 60, 30 2, 1, 25, 25 3, 2, 80, 40 4, 1, 40, 40 5, 1, 20, 20 6, 3, 150, 50 for this specific subset, the expected output should ideally be: team1: 0, 1 (total: 186) team2: 2, 5, 6 (total: 195) up to now the solution I have been using is to balance out each team by making each team pick the group with highest ranking within the subset turn by turn. The team who picks is the one with the currently lowest average rank unless one is already full. If one team is already full the other team tries to complete itself with groups that would make the rank gap as small as possible. This solution turns out to have issues with frequent edge cases and I'm looking for a better solution, or some fine-tuning that could be made. In most cases, players seems to want teams of 5 people and queue in group of 2. Our average subset when 2 teams of 5 are chosen is made of about 14 players if that may be of any help.

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  • How to visually "connect" skybox edges with terrain model

    - by David
    I'm working on a simple airplane game where I use skybox cube rendered using disabled depth test. Very close to the bottom side of the skybox is my terrain model. What bothers me is that the terrain is not connected to the skybox bottom. This is not visible while the plane flies low, but as it gets some altitude, the terrain looks smaller because of the perspective. Since the skybox center is always same as the camera position, the skybox moves with the plane, but the terrain goes into the distance. Ok, I think you understand the problem. My question is how to fix it. It's an airplane game so limiting max altitude is not possible. I thought about some way to stretch terrain to always cover whole bottom side of the skybox cube, but that doesn't feel right and I don't even know how would I calculate new terrain dimensions every frame. Here are some screenshot of games where you can clearly see the problem: (oops, I cannot post images yet) darker brown is the skybox bottom here: http://i.stack.imgur.com/iMsAf.png untextured brown is the skybox bottom here: http://i.stack.imgur.com/9oZr7.png

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  • Deformation of Sphere using Transformations

    - by Mert Toka
    I have a graphic related question. I need to have a transformation matrix that I have no idea about what it is. The problem is to create right image from the right sphere. I created those images in Maya, but I need some matrices for the graphics course. Here is the image: Our professor told us to use some sine and cosine in our transformations, but I have no idea what he meant. I thought of intersecting a plane from the grid(that is xz plane) and sphere, and then scaling down the resulting circle. Would that work? I also checked this paper, however it looks like a bit advanced for me. Another thing is I guess that paper is not about the same type of information I was looking for. It would be great if you could help me.

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  • How do I implement smooth movement in a Box2D platform game?

    - by Romeo
    I have implemented a character in JBox2D which moves with the help of a wheel rotating at the bottom of it. The movement is the best result I've had 'till now but it's a little glitchy when the character stands on the edge. So I am thinking should I use five smaller wheels instead of a big wheel. The wheel/wheels will not be visible in the finished product, now they are drawn for debugging. Here is a video. Is there a better way to do this using JBox2D?

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  • How to Make Objects Fall Faster in a Physics Simulation

    - by David Dimalanta
    I used the collision physics (i.e. Box2d, Physics Body Editor) and implemented onto the java code. I'm trying to make the fall speed higher according to the examples: It falls slower if light object (i.e. feather). It falls faster depending on the object (i.e. pebble, rock, car). I decided to double its falling speed for more excitement. I tried adding the mass but the speed of falling is constant instead of gaining more speed. check my code that something I put under input processor's touchUp() return method under same roof of the class that implements InputProcessor and Screen: @Override public boolean touchUp(int screenX, int screenY, int pointer, int button) { // TODO Touch Up Event if(is_Next_Fruit_Touched) { BodyEditorLoader Fruit_Loader = new BodyEditorLoader(Gdx.files.internal("Shape_Physics/Fruity Physics.json")); Fruit_BD.type = BodyType.DynamicBody; Fruit_BD.position.set(x, y); FixtureDef Fruit_FD = new FixtureDef(); // --> Allows you to make the object's physics. Fruit_FD.density = 1.0f; Fruit_FD.friction = 0.7f; Fruit_FD.restitution = 0.2f; MassData mass = new MassData(); mass.mass = 5f; Fruit_Body[n] = world.createBody(Fruit_BD); Fruit_Body[n].setActive(true); // --> Let your dragon fall. Fruit_Body[n].setMassData(mass); Fruit_Body[n].setGravityScale(1.0f); System.out.println("Eggs... " + n); Fruit_Loader.attachFixture(Fruit_Body[n], Body, Fruit_FD, Fruit_IMG.getWidth()); Fruit_Origin = Fruit_Loader.getOrigin(Body, Fruit_IMG.getWidth()).cpy(); is_Next_Fruit_Touched = false; up = y; Gdx.app.log("Initial Y-coordinate", "Y at " + up); //Once it's touched, the next fruit will set to drag. if(n < 50) { n++; }else{ System.exit(0); } } return true; } And take note, at show() method , the view size from the camera is at 720x1280: camera_1 = new OrthographicCamera(); camera_1.viewportHeight = 1280; camera_1.viewportWidth = 720; camera_1.position.set(camera_1.viewportWidth * 0.5f, camera_1.viewportHeight * 0.5f, 0f); camera_1.update(); I know it's a good idea to add weight to make the falling object falls faster once I released the finger from the touchUp() after I picked the object from the upper right of the screen but the speed remains either constant or slow. How can I solve this? Can you help?

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  • Character movement on a 2D tile map

    - by Chris Morris
    I'm working at making a HTML5 game. Top down, closest thing I can equate it to is the gameboy zeldas, but open world and no rooms. What I have so far is a procedurally generated map in a multi dimensional array. And a starting position on the map. Along with this I have an array of movable and non movable tile ID's. I also have a class for my player and have him being rendered out in the center of the starting tile. My problem however is getting the movement sorted out for the player. I want to be able to have the character free move around the map (pixel by pixel essentially) ontop of this 2D generated world. Ideally this would allow the user to move around the walk able area of the canvas. this is simple enough for me to do, but I am having problems now moving the world. If the user is 20% from the edge of the screen i want the world to start panning in the direction the player is heading. But I'm rather lacking in ideas of how to do this. I've looked around for some tutorials, but am coming up blank on ideas of how to generate the playable area (zoomed in) and to then move this generated area under the player when they reach near the end of the screen. My current idea was to generate a certain amount of tiles full size to fill the screen and place the player i the middle. Then when the user approaches the edge of the screen start generating the tiles offset by the distance moved and the direction. I can kind of see this working but I really have no idea if this is the best or easiest to code of methods for generating the world. sorry for the lack of code but I'm still just in the theory stages of working this all out.

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  • How can I selectively update XNA GameComponents?

    - by Bill
    I have a small 2D game I'm working on in XNA. So far, I have a player-controlled ship that operates on vector thrust and is terribly fun to spin around in circles. I've implemented this as a DrawableGameComponent and registered it with the game using game.Components.Add(this) in the Ship object constructor. How can I implement features like pausing and a menu system with my current implementation? Is it possible to set certain GameComponents to not update? Is this something for which I should even be using a DrawableGameComponent? If not, what are more appropriate uses for this?

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  • OpenGL ES 2.0 example for JOGL

    - by fjdutoit
    I've scoured the internet for the last few hours looking for an example of how to run even the most basic OpenGL ES 2 example using JOGL but "by Jupiter!" it has been a total fail. I tried converting the android example from the OpenGL ES 2.0 Programming Guide examples (and at the same time looking at the WebGL example -- which worked fine) yet without any success. Are there any examples out there? If anyone else wants some extra help regarding this question see this thread on the official Jogamp forum.

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  • Split a 2D scene in layers or have a z coordinate

    - by Bane
    I am in the process of writing a 2D game engine, and a dilemma emerged. Let me explain the situation... I have a Scene class, to which various objects can be added (Drawable, ParticleEmitter, Light2D, etc), and as this is a 2D scene, things will obviously be drawn over each other. My first thought was that I could have basic add and remove methods, but I soon realized that then there would be no way for the programmer to control the order in which things were drawn. So I can up with two options, each with its pros and cons. A) Would be to split the scene in layers. By that I mean instead of having the scene be a container of objects, have it be a container of layers, which are in turn the containers of objects. B) Would require to have some kind of z-coordinate, and then have the scene sorted so objects with lower z get drawn first. Option A is pretty solid, but the problem is with the lights. In what layer do I add it? Does it work cross-layer? On all bottom layers? And I still need the Z coordinate to calculate the shadow! Option B would require me to change all my code from having Vector2D positions, to some kind of class that inherits from Vector2D and adds a z coordinate to it (I don't want it to be a Vector3D because I still need all the same methods the 2D kind has, just with .z clamped on). Am I missing something? Is there an alternative to these methods? I'm working in Javascript, if that makes a difference.

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  • How do you properly organize a commercial game?

    - by Reactorcore
    For the past months I've been studying programming and I've finally learned how to code, but one thing that is confusing me is how to properly organize the design of a game project - code wise. The game I'm building is a pretty standard commercial game. It has the basic components of a normal game: A world, characters and items interacting with each other and all of this is run by game manager. Basically you play as a hero in a world and do stuff. Fight, explore and interact. Think of your standard adventure game that starts off with an intro, goes to the menu system, then gets into the game and back to the menu. Pretty much like 99% of any commercial game or otherwise serious game projects. Thats what I'm aiming at. The problem is: How do you properly code a commercial game architecture? How do you organize it? How do you make it not become unmaintainable spaghetti code? What specific things to keep in mind when building this, codewise? How you can help me: a) Please tell how do you code your own game projects. What is your thought-process when designing the architecture? b) Recommend books, blogs, tutorials, videos or anything else on how to organize a commercial video game. c) Give hints and tips on do's/don'ts when building a game, codewise. Please help!

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  • In an Entity-Component-System Engine, How do I deal with groups of dependent entities?

    - by John Daniels
    After going over a few game design patterns, I have settle with Entity-Component-System (ES System) for my game engine. I've reading articles (mainly T=Machine) and review some source code and I think I got enough to get started. There is just one basic idea I am struggling with. How do I deal with groups of entities that are dependent on each other? Let me use an example: Assume I am making a standard overhead shooter (think Jamestown) and I want to construct a "boss entity" with multiple distinct but connected parts. The break down might look like something like this: Ship body: Movement, Rendering Cannon: Position (locked relative to the Ship body), Tracking\Fire at hero, Taking Damage until disabled Core: Position (locked relative to the Ship body), Tracking\Fire at hero, Taking Damage until disabled, Disabling (er...destroying) all other entities in the ship group My goal would be something that would be identified (and manipulated) as a distinct game element without having to rewrite subsystem form the ground up every time I want to build a new aggregate Element. How do I implement this kind of design in ES System? Do I implement some kind of parent-child entity relationship (entities can have children)? This seems to contradict the methodology that Entities are just empty container and makes it feel more OOP. Do I implement them as separate entities, with some kind of connecting Component (BossComponent) and related system (BossSubSystem)? I can't help but think that this will be hard to implement since how components communicate seem to be a big bear trap. Do I implement them as one Entity, with a collection of components (ShipComponent, CannonComponents, CoreComponent)? This one seems to veer way of the ES System intent (components here seem too much like heavy weight entities), but I'm know to this so I figured I would put that out there. Do I implement them as something else I have mentioned? I know that this can be implemented very easily in OOP, but my choosing ES over OOP is one that I will stick with. If I need to break with pure ES theory to implement this design I will (not like I haven't had to compromise pure design before), but I would prefer to do that for performance reason rather than start with bad design. For extra credit, think of the same design but, each of the "boss entities" were actually connected to a larger "BigBoss entity" made of a main body, main core and 3 "Boss Entities". This would let me see a solution for at least 3 dimensions (grandparent-parent-child)...which should be more than enough for me. Links to articles or example code would be appreciated. Thanks for your time.

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  • How do I adjust the origin of rotation for a group of sprites?

    - by Jon
    I am currently grouping sprites together, then applying a rotation transformation on draw: private void UpdateMatrix(ref Vector2 origin, float radians) { Vector3 matrixorigin = new Vector3(origin, 0); _rotationMatrix = Matrix.CreateTranslation(-matrixorigin) * Matrix.CreateRotationZ(radians) * Matrix.CreateTranslation(matrixorigin); } Where the origin is the Centermost point of my group of sprites. I apply this transformation to each sprite in the group. My problem is that when I adjust the point of origin, my entire sprite group will re-position itself on screen. How could I differentiate the point of rotation used in the transformation, from the position of the sprite group? Is there a better way of creating this transformation matrix? EDIT Here is the relevant part of the Draw() function: Matrix allTransforms = _rotationMatrix * camera.GetTransformation(); spriteBatch.Begin(SpriteSortMode.BackToFront, null, null, null, null, null, allTransforms); for (int i = 0; i < _map.AllParts.Count; i++) { for (int j = 0; j < _map.AllParts[0].Count; j++) { spriteBatch.Draw(_map.AllParts[i][j].Texture, _map.AllParts[i][j].Position, null, Color.White, 0, _map.AllParts[i][j].Origin, 1.0f, SpriteEffects.None, 0f); } } This all works fine, again, the problem is that when a rotation is set and the point of origin is changed, the sprite group's position is offset on screen. I am trying to figure out a way to adjust the point of origin without causing a shift in position. EDIT 2 At this point, I'm looking for workarounds as this is not working. Does anyone know of a better way to rotate a group of sprites in XNA? I need a method that will allow me to modify the point of rotation (origin) without affecting the position of the sprite group on screen.

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  • Game Institute Math Courses

    - by W3Geek
    I'm 21 years old and I suck at math, I mean really bad. I don't have the necessary logic to apply it towards programming. I would like to learn the math and logic of applying it. I found Game Institute (http://www.gameinstitute.com) awhile back and heard a lot of praise about them. Are there Math courses any good? Thank you. Edit: My high school was terrible and did not prepare me for any math. I am fairly decent at programming, I just don't have the logic to apply any mathematics to programming, as an example I don't understand the algorithm of finding the size of a user's screen. Yes I have heard of KhanAcademy (http://www.khanacademy.org/) and I have completed a lot of maths on his website but I still don't have the logic to apply any of it to programming.

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  • Self learning automated movement

    - by Super1
    I am trying to make a small demo in Javascript, I have a black border and a car the car travels randomly and a line is drawn of its trail. When the user click inside the area it creates an object (we'll call this the wall). If the car hits the wall then it goes back 3 paces and tries a different route. When its hit the wall it needs to log down its location so it does NOT make that mistake again. Here is my example: http://jsfiddle.net/Jtq3E/ How can I get the car to move by itself and create a trail?

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  • How to move a directional light according to the camera movement?

    - by Andrea Benedetti
    Given a light direction, how can I move it according to the camera movement, in a shader? Think that an artist has setup a scene (e.g., in 3DSMax) with a mesh in center of that and a directional light with a position and a target. From this position and target I've calculated the light direction. Now I want to use the same direction in my lighting equation but, obviously, I want that this light moves correctly with the camera. Thanks.

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  • How to keep balance / Unlock items / achievement rules

    - by Mark Knol
    I'm working on an engine for a game, too learn javascript and just because its fun. I'm a flashdeveloper, I know how to build websites. Now making games is a different challenge, javascript is a challenge, but I'd love to learn how to structure code and what patterns are common. I dont mind if the game ever finish, I'm mostly interested in the programming part of it. I dont have a particular endresult in mind, so I'll see where it takes me. I currently have a system where you can buy items. The items cost a specified amount of gold, silver, diamonds etc. When you have selected and bought the item, it takes time before getting rewarded. When time is over, you are getting rewarded with other properties (gold, energy, diamonds). For example, you can buy an apple for 50gold, It takes a minute, you get rewarded with 75energy. Or if you take a run, it cost 50energy, it takes 5minutes, reward is 25gold and 25silver. These definitions is what i call actions. Currently I already have a system where this already works and I can define as much actions with as much properties as I want. The definitions I have kinda looks like this: {id:101, category:544, onInit:{gold:-75}, onComplete:{energy:75}, time:2000, name:"Apple", locked: false} {id:102, category:544, onInit:{gold:-135}, onComplete:{energy:145}, time:2000, name:"Banana", locked: false} {id:106, category:302, onInit:{energy:-50, power: -25}, onComplete:{gold:100, diamonds:2}, time:10000, name:"Run", locked: false} {id:107, category:302, onInit:{energy:-70, silver: -55}, onComplete:{gold:100}, time:10000, name:"Dance", locked: false} {id:108, category:302, onInit:{energy:-230, power: -355}, onComplete:{gold:70, silver:70}, time:10000, name:"Fitness", locked: false} Now, I would love to add a system where I can lock/unlock the actions using achievement rules. Lets say, if you buy 10 apples, you unlock a new action, like bananas which cost more, and reward more. In the future I maybe want to restrict achievements and actions to levels. I am kinda stuck how to structure this. I have 2 questions: Which patterns are used to define achievements? How/where are they defined? Should it be part of the action, or should it be a separate controller? Is it a good idea to register all completed actions to it? I think I want multiple types of achievement rules, Id love to hear some ideas how to develop it. How do you create/find a good balance, so the user does not get stuck or can cheat by repeat a pattern of actions to get too much rewards. I know there is not a simple answer and i'm lacking of a good game-concept, but I wonder if anyone created such a game and how you dealed and played with it.

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  • How AlphaBlend Blendstate works in XNA 4 when accumulighting light into a RenderTarget?

    - by cubrman
    I am using a Deferred Rendering engine from Catalin Zima's tutorial: His lighting shader returns the color of the light in the rgb channels and the specular component in the alpha channel. Here is how light gets accumulated: Game.GraphicsDevice.SetRenderTarget(LightRT); Game.GraphicsDevice.Clear(Color.Transparent); Game.GraphicsDevice.BlendState = BlendState.AlphaBlend; // Continuously draw 3d spheres with lighting pixel shader. ... Game.GraphicsDevice.BlendState = BlendState.Opaque; MSDN states that AlphaBlend field of the BlendState class uses the next formula for alphablending: (source × Blend.SourceAlpha) + (destination × Blend.InvSourceAlpha), where "source" is the color of the pixel returned by the shader and "destination" is the color of the pixel in the rendertarget. My question is why do my colors are accumulated correctly in the Light rendertarget even when the new pixels' alphas equal zero? As a quick sanity check I ran the following code in the light's pixel shader: float specularLight = 0; float4 light4 = attenuation * lightIntensity * float4(diffuseLight.rgb,specularLight); if (light4.a == 0) light4 = 0; return light4; This prevents lighting from getting accumulated and, subsequently, drawn on the screen. But when I do the following: float specularLight = 0; float4 light4 = attenuation * lightIntensity * float4(diffuseLight.rgb,specularLight); return light4; The light is accumulated and drawn exactly where it needs to be. What am I missing? According to the formula above: (source x 0) + (destination x 1) should equal destination, so the "LightRT" rendertarget must not change when I draw light spheres into it! It feels like the GPU is using the Additive blend instead: (source × Blend.One) + (destination × Blend.One)

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  • How can I implement an Iris Wipe effect?

    - by Vandell
    For those who doesn't know: An iris wipe is a wipe that takes the shape of a growing or shrinking circle. It has been frequently used in animated short subjects, such as those in the Looney Tunes and Merrie Melodies cartoon series, to signify the end of a story. When used in this manner, the iris wipe may be centered around a certain focal point and may be used as a device for a "parting shot" joke, a fourth wall-breaching wink by a character, or other purposes. Example from flasheff.com Your answer may or may not include a coding sample, a language agnostic explanation is considered enough.

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