Search Results

Search found 25660 results on 1027 pages for 'dotnetnuke development'.

Page 461/1027 | < Previous Page | 457 458 459 460 461 462 463 464 465 466 467 468  | Next Page >

• Unable to Call Instantiate in Class Member Function

  - by onguarde

  The following javascript is attached to a gameObject. var instance : GameObject; class eg_class { function eg_func(){ var thePrefab : GameObject; instance = Instantiate(thePrefab); } } Error, Unknown identifier: 'instance'. Unknown identifier: 'Instantiate'. Questions, 1) Why is it that "instance" cannot be accessed within a class? Isn't it supposed to be a public variable? 2) "Instantiate" function works in Start()/Update() root functions. Is there a way to make it work from within member functions? Thanks in advance!

  Read the article

• Making a Camera look at a target Vector

  - by Peteyslatts

  I have a camera that works as long as its stationary. Now I'm trying to create a child class of that camera class that will look at its target. The new addition to the class is a method called SetTarget(). The method takes in a Vector3 target. The camera wont move but I need it to rotate to look at the target. If I just set the target, and then call CreateLookAt() (which takes in position, target, and up), when the object gets far enough away and underneath the camera, it suddenly flips right side up. So I need to transform the up vector, which currently always stays at Vector3.Up. I feel like this has something to do with taking the angle between the old direction vector and the new one (which I know can be expressed by target - position). I feel like this is all really vague, so here's the code for my base camera class: public class BasicCamera : Microsoft.Xna.Framework.GameComponent { public Matrix view { get; protected set; } public Matrix projection { get; protected set; } public Vector3 position { get; protected set; } public Vector3 direction { get; protected set; } public Vector3 up { get; protected set; } public Vector3 side { get { return Vector3.Cross(up, direction); } protected set { } } public BasicCamera(Game game, Vector3 position, Vector3 target, Vector3 up) : base(game) { this.position = position; this.direction = target - position; this.up = up; CreateLookAt(); projection = Matrix.CreatePerspectiveFieldOfView( MathHelper.PiOver4, (float)Game.Window.ClientBounds.Width / (float)Game.Window.ClientBounds.Height, 1, 500); } public override void Update(GameTime gameTime) { // TODO: Add your update code here CreateLookAt(); base.Update(gameTime); } } And this is the code for the class that extends the above class to look at its target. class TargetedCamera : BasicCamera { public Vector3 target { get; protected set; } public TargetedCamera(Game game, Vector3 position, Vector3 target, Vector3 up) : base(game, position, target, up) { this.target = target; } public void SetTarget(Vector3 target) { direction = target - position; } protected override void CreateLookAt() { view = Matrix.CreateLookAt(position, target, up); } }

  Read the article

• Projective texture and deferred lighting

  - by Vodácek

  In my previous question, I asked whether it is possible to do projective texturing with deferred lighting. Now (more than half a year later) I have a problem with my implementation of the same thing. I am trying to apply this technique in light pass. (my projector doesn't affect albedo). I have this projector View a Projection matrix: Matrix projection = Matrix.CreateOrthographicOffCenter(-halfWidth * Scale, halfWidth * Scale, -halfHeight * Scale, halfHeight * Scale, 1, 100000); Matrix view = Matrix.CreateLookAt(Position, Target, Vector3.Up); Where halfWidth and halfHeight is are half of the texture's width and height, Position is the Projector's position and target is the projector's target. This seems to be ok. I am drawing full screen quad with this shader: float4x4 InvViewProjection; texture2D DepthTexture; texture2D NormalTexture; texture2D ProjectorTexture; float4x4 ProjectorViewProjection; sampler2D depthSampler = sampler_state { texture = <DepthTexture>; minfilter = point; magfilter = point; mipfilter = point; }; sampler2D normalSampler = sampler_state { texture = <NormalTexture>; minfilter = point; magfilter = point; mipfilter = point; }; sampler2D projectorSampler = sampler_state { texture = <ProjectorTexture>; AddressU = Clamp; AddressV = Clamp; }; float viewportWidth; float viewportHeight; // Calculate the 2D screen position of a 3D position float2 postProjToScreen(float4 position) { float2 screenPos = position.xy / position.w; return 0.5f * (float2(screenPos.x, -screenPos.y) + 1); } // Calculate the size of one half of a pixel, to convert // between texels and pixels float2 halfPixel() { return 0.5f / float2(viewportWidth, viewportHeight); } struct VertexShaderInput { float4 Position : POSITION0; }; struct VertexShaderOutput { float4 Position :POSITION0; float4 PositionCopy : TEXCOORD1; }; VertexShaderOutput VertexShaderFunction(VertexShaderInput input) { VertexShaderOutput output; output.Position = input.Position; output.PositionCopy=output.Position; return output; } float4 PixelShaderFunction(VertexShaderOutput input) : COLOR0 { float2 texCoord =postProjToScreen(input.PositionCopy) + halfPixel(); // Extract the depth for this pixel from the depth map float4 depth = tex2D(depthSampler, texCoord); //return float4(depth.r,0,0,1); // Recreate the position with the UV coordinates and depth value float4 position; position.x = texCoord.x * 2 - 1; position.y = (1 - texCoord.y) * 2 - 1; position.z = depth.r; position.w = 1.0f; // Transform position from screen space to world space position = mul(position, InvViewProjection); position.xyz /= position.w; //compute projection float3 projection=tex2D(projectorSampler,postProjToScreen(mul(position,ProjectorViewProjection)) + halfPixel()); return float4(projection,1); } In first part of pixel shader is recovered position from G-buffer (this code I am using in other shaders without any problem) and then is tranformed to projector viewprojection space. Problem is that projection doesn't appear. Here is an image of my situation: The green lines are the rendered projector frustum. Where is my mistake hidden? I am using XNA 4. Thanks for advice and sorry for my English. EDIT: Shader above is working but projection was too small. When I changed the Scale property to a large value (e.g. 100), the projection appears. But when the camera moves toward the projection, the projection expands, as can bee seen on this YouTube video.

  Read the article

• How to derive euler angles from matrix or quaternion?

  - by KlashnikovKid

  Currently working on steering behavior for my AI and just hit a little mathematical bump. I'm in the process of writing an align function, which basically tries to match the agent's orientation with a target orientation. I've got a good source material for implementing this behavior but it uses euler angles to calculate the rotational delta, acceleration, and so on. This is nice, however I store orientation as a quaternion and the math library I'm using doesn't provide any functionality for deriving the euler angles. But if it helps I also have rotational matrices at my disposal too. What would be the best way to decompose the quaternion or rotational matrix to get the euler information? I found one source for decomposing the matrix, but I'm not quite getting the correct results. I'm thinking it may be a difference of column/row ordering of my matrices but then again, math isn't my strong point. http://nghiaho.com/?page_id=846

  Read the article

• Creating a frozen bubble clone

  - by Vaughan Hilts

  This photo illustrates the environment: http://i.imgur.com/V4wbp.png I'll shoot the cannon, it'll bounce off the wall and it's SUPPOSED to stick to the bubble. It does at pretty much every other angle. The problem is always reproduced here, when hit off the wall into those bubbles. It also exists in other cases, but I'm not sure what triggers it. What actually happens: The ball will sometimes set to the wrong cell, and my "dropping" code will detect it as a loner and drop it off the stage. *There are many implementations of "Frozen Bubble" on the web, but I can't for the life of me find a good explanation as to how the algorithm for the "Bubble Sticking" works. * I see this: http://www.wikiflashed.com/wiki/BubbleBobble https://frozenbubblexna.svn.codeplex.com/svn/FrozenBubble/ But I can't figure out the algorithims... could anyone explain possibly the general idea behind getting the balls to stick? Code in question: //Counstruct our bounding rectangle for use var nX = currentBall.x + ballvX * gameTime; var nY = currentBall.y - ballvY * gameTime; var movingRect = new BoundingRectangle(nX, nY, 32, 32); var able = false; //Iterate over the cells and draw our bubbles for (var x = 0; x < 8; x++) { for (var y = 0; y < 12; y++) { //Get the bubble at this layout var bubble = bubbleLayout[x][y]; var rowHeight = 27; //If this slot isn't empty, draw if (bubble != null) { var bx = 0, by = 0; if (y % 2 == 0) { bx = x * 32 + 270; by = y * 32 + 45; } else { bx = x * 32 + 270 + 16; by = y * 32 + 45; } //Check var targetBox = new BoundingRectangle(bx, by, 32, 32); if (targetBox.intersects(movingRect)) { able = true; } } } } cellY = Math.round((currentBall.y - 45) / 32); if (cellY % 2 == 0) cellX = Math.round((currentBall.x - 270) / 32); else cellX = Math.round((currentBall.x - 270 - 16) / 32); Any ideas are very much welcome. Things I've tried: Flooring and Ceiling values Changing the wall bounce to a lower value Slowing down the ball None of these seem to affect it. Is there something in my math I'm not getting?

  Read the article

• collision detection problems - Javascript/canvas game

  - by Tom Burman

  Ok here is a more detailed version of my question. What i want to do: i simply want the have a 2d array to represent my game map. i want a player sprite and i want that sprite to be able to move around my map freely using the keyboard and also have collisions with certain tiles of my map array. i want to use very large maps so i need a viewport. What i have: I have a loop to load the tile images into an array: /Loop to load tile images into an array var mapTiles = []; for (x = 0; x <= 256; x++) { var imageObj = new Image(); // new instance for each image imageObj.src = "images/prototype/"+x+".jpg"; mapTiles.push(imageObj); } I have a 2d array for my game map: //Array to hold map data var board = [ [1,2,3,4,3,4,3,4,5,6,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1], [17,18,19,20,19,20,19,20,21,22,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1], [33,34,35,36,35,36,35,36,37,38,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1], [49,50,51,52,51,52,51,52,53,54,1,1,1,1,1,1,1,1,1,1,1,1,1,197,198,199,1,1,1,1], [65,66,67,68,146,147,67,68,69,70,1,1,1,1,1,1,1,1,216,217,1,1,1,213,214,215,1,1,1,1], [81,82,83,161,162,163,164,84,85,86,1,1,1,1,1,1,1,1,232,233,1,1,1,229,230,231,1,1,1,1], [97,98,99,177,178,179,180,100,101,102,1,1,1,1,59,1,1,1,248,249,1,1,1,245,246,247,1,1,1,1], [1,1,238,1,1,1,1,239,240,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1], [216,217,254,1,1,1,1,255,256,1,204,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1], [232,233,1,1,1,117,118,1,1,1,220,1,1,119,120,1,1,1,1,1,1,1,1,1,1,1,119,120,1,1], [248,249,1,1,1,133,134,1,1,1,1,1,1,135,136,1,1,1,1,1,1,59,1,1,1,1,135,136,1,1], [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1], [1,1,216,217,1,1,1,1,1,1,60,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1], [1,1,232,233,1,1,1,1,1,1,1,1,1,1,1,1,1,1,204,1,1,1,1,1,1,1,1,1,1,1], [1,1,248,249,1,1,1,1,1,1,1,1,1,1,1,1,1,1,220,1,1,1,1,1,1,216,217,1,1,1], [1,1,1,1,1,1,1,1,1,1,1,1,149,150,151,1,1,1,1,1,1,1,1,1,1,232,233,1,1,1], [12,12,12,12,12,12,12,13,1,1,1,1,165,166,167,1,1,1,1,1,1,119,120,1,1,248,249,1,1,1], [28,28,28,28,28,28,28,29,1,1,1,1,181,182,183,1,1,1,1,1,1,135,136,1,1,1,1,1,1,1], [44,44,44,44,44,15,28,29,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1], [1,1,1,1,1,27,28,29,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1], [1,1,1,1,1,27,28,29,1,1,1,1,1,1,1,1,1,59,1,1,197,198,199,1,1,1,1,119,120,1], [1,1,1,1,1,27,28,29,1,1,216,217,1,1,1,1,1,1,1,1,213,214,215,1,1,1,1,135,136,1], [1,1,1,1,1,27,28,29,1,1,232,233,1,1,1,1,1,1,1,1,229,230,231,1,1,1,1,1,1,1], [1,1,1,1,1,27,28,29,1,1,248,249,1,1,1,1,1,1,1,1,245,246,247,1,1,1,1,1,1,1], [1,1,1,197,198,199,28,29,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1], [1,1,1,213,214,215,28,29,1,1,1,1,1,60,1,1,1,1,204,1,1,1,1,1,1,1,1,1,1,1], [1,1,1,229,230,231,28,29,1,1,1,1,1,1,1,1,1,1,220,1,1,1,1,119,120,1,1,1,1,1], [1,1,1,245,246,247,28,29,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,135,136,1,1,60,1,1], [1,1,1,1,1,27,28,29,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1], [1,1,1,1,1,27,28,29,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1] ]; I have my loop to place the correct tile sin the correct positions: //Loop to place tiles onto screen in correct position for (x = 0; x <= viewWidth; x++){ for (y = 0; y <= viewHeight; y++){ var width = 32; var height = 32; context.drawImage(mapTiles[board[y+viewY][x+viewX]],x*width, y*height); } } I Have my player object : //Place player object context.drawImage(playerImg, (playerX-viewX)*32,(playerY-viewY)*32, 32, 32); I have my viewport setup: //Set viewport pos viewX = playerX - Math.floor(0.5 * viewWidth); if (viewX < 0) viewX = 0; if (viewX+viewWidth > worldWidth) viewX = worldWidth - viewWidth; viewY = playerY - Math.floor(0.5 * viewHeight); if (viewY < 0) viewY = 0; if (viewY+viewHeight > worldHeight) viewY = worldHeight - viewHeight; I have my player movement: canvas.addEventListener('keydown', function(e) { console.log(e); var key = null; switch (e.which) { case 37: // Left if (playerY > 0) playerY--; break; case 38: // Up if (playerX > 0) playerX--; break; case 39: // Right if (playerY < worldWidth) playerY++; break; case 40: // Down if (playerX < worldHeight) playerX++; break; } My Problem: I have my map loading an it looks fine, but my player position thinks it's on a different tile to what it actually is. So for instance, i know that if my player moves left 1 tile, the value of that tile should be 2, but if i print out the value it should be moving to (2), it comes up with a different value. How ive tried to solve the problem: I have tried swap X and Y values for the initialization of my player, for when my map prints. If i swap the x and y values in this part of my code: context.drawImage(mapTiles[board[y+viewY][x+viewX]],x*width, y*height); The map doesnt get draw correctly at all and tiles are placed all in random positions or orientations IF i sway the x and y values for my player in this line : context.drawImage(playerImg, (playerX-viewX)*32,(playerY-viewY)*32, 32, 32); The players movements are inversed, so up and down keys move my player left and right viceversa. My question: Where am i going wrong in my code, and how do i solve it so i have my map looking like it should and my player moving as it should as well as my player returning the correct tileID it is standing on or moving too. Thanks Again ALSO Here is a link to my whole code: prototype

  Read the article

• How to properly do weapon cool-down reload timer in multi-player laggy environment?

  - by John Murdoch

  I want to handle weapon cool-down timers in a fair and predictable way on both client on server. Situation: Multiple clients connected to server, which is doing hit detection / physics Clients have different latency for their connections to server ranging from 50ms to 500ms. They want to shoot weapons with fairly long reload/cool-down times (assume exactly 10 seconds) It is important that they get to shoot these weapons close to the cool-down time, as if some clients manage to shoot sooner than others (either because they are "early" or the others are "late") they gain a significant advantage. I need to show time remaining for reload on player's screen Clients can have clocks which are flat-out wrong (bad timezones, etc.) What I'm currently doing to deal with latency: Client collects server side state in a history, tagged with server timestamps Client assesses his time difference with server time: behindServerTimeNs = (behindServerTimeNs + (System.nanoTime() - receivedState.getServerTimeNs())) / 2 Client renders all state received from server 200 ms behind from his current time, adjusted by what he believes his time difference with server time is (whether due to wrong clocks, or lag). If he has server states on both sides of that calculated time, he (mostly LERP) interpolates between them, if not then he (LERP) extrapolates. No other client-side prediction of movement, e.g., to make his vehicle seem more responsive is done so far, but maybe will be added later So how do I properly add weapon reload timers? My first idea would be for the server to send each player the time when his reload will be done with each world state update, the client then adjusts it for the clock difference and thus can estimate when the reload will be finished in client-time (perhaps considering also for latency that the shoot message from client to server will take as well?), and if the user mashes the "shoot" button after (or perhaps even slightly before?) that time, send the shoot event. The server would get the shoot event and consider the time shot was made as the server time when it was received. It would then discard it if it is nowhere near reload time, execute it immediately if it is past reload time, and hold it for a few physics cycles until reload is done in case if it was received a bit early. It does all seem a bit convoluted, and I'm wondering whether it will work (e.g., whether it won't be the case that players with lower ping get better reload rates), and whether there are more elegant solutions to this problem.

  Read the article

• What would be the best mean for a gui with a lot of FX in Unity

  - by Lionel Barret

  The game I am working on (we are in R&D) is based almost exclusively on a windowed gui with a lot of FX (fading, growing, etc). We will also likely need custom widgets (like a sound recording graph). The game will be made with Unity and from what I heard, the default gui system has quite a bad rep, it is too slow for many usages. So, I wondering what would be the best way to do what we need.

  Read the article

• How to deal with Character body parts from Design to Cocos2d

  - by Edwin Soho

  I'm trying to figure out the pattern the game developers use together with game designers: See the picture below with the independent parts: Questions: 1) Should I create different image parts from different body parts or keep frame by frame animaton? (I know both can be used, but I'm trying to figure what is commonly used in the industry) 2) If I'm going to generate different image parts from different body parts (which is I thing is more logical) how would I export that to Cocos2d (Vector or Bitmap)?

  Read the article

• Wrong faces culled in OpenGL when drawing a rectangular prism

  - by BadSniper

  I'm trying to learn opengl. I did some code for building a rectangular prism. I don't want to draw back faces so I used glCullFace(GL_BACK), glEnable(GL_CULL_FACE);. But I keep getting back faces also when viewing from front and also sometimes when rotating sides are vanishing. Can someone point me in right direction? glPolygonMode(GL_FRONT,GL_LINE); // draw wireframe polygons glColor3f(0,1,0); // set color green glCullFace(GL_BACK); // don't draw back faces glEnable(GL_CULL_FACE); // don't draw back faces glTranslatef(-10, 1, 0); // position glBegin(GL_QUADS); // face 1 glVertex3f(0,-1,0); glVertex3f(0,-1,2); glVertex3f(2,-1,2); glVertex3f(2,-1,0); // face 2 glVertex3f(2,-1,2); glVertex3f(2,-1,0); glVertex3f(2,5,0); glVertex3f(2,5,2); // face 3 glVertex3f(0,5,0); glVertex3f(0,5,2); glVertex3f(2,5,2); glVertex3f(2,5,0); // face 4 glVertex3f(0,-1,2); glVertex3f(2,-1,2); glVertex3f(2,5,2); glVertex3f(0,5,2); // face 5 glVertex3f(0,-1,2); glVertex3f(0,-1,0); glVertex3f(0,5,0); glVertex3f(0,5,2); // face 6 glVertex3f(0,-1,0); glVertex3f(2,-1,0); glVertex3f(2,5,0); glVertex3f(0,5,0); glEnd();

  Read the article

• Any good web frameworks for asynchronous multiplayer games?

  - by Steven Stadnicki

  I'm trying to craft a site for web-based (original) board games, and my client (currently written in Actionscript, but that's highly fungible) works fine - I can play solitaire games in the client - but it has nothing to connect to. What I'm looking for is a server framework for handling accounts/authentication and game tracking: something that would let players log in, show them a list of their current games, let them invite friends to new games, let them make moves in the games they have open, etc. I'm flexible on language; obviously I'm going to have to write a lot of server code to handle the actual game logic, but that should be straightforward enough. I'm more concerned with how to handle the user (and game) DBs, though suggestions for a good server framework for communicating with the DBs (and serving up, most likely, JSON for client communications) are also welcome. Right now my leaning is towards Ruby (probably with Rails) but as far as I can determine it would be a pretty good chunk of effort to set up the necessary databases, so having something even higher-level would be really useful to me.

  Read the article

• cocos2d event handler not fired when reentering scene

  - by Adam Freund

  I am encountering a very strange problem with my cocos2d app. I add a sprite to the page and have an event handler linked to it which replaces the scene with another scene. On that page I have another button to take me back to the original scene. When I am back on the original scene, the eventHandler doesn't get fired when I click on the sprite. Below is the relevant code. Thanks for any help! CCMenuItemImage *backBtnImg = [CCMenuItemImage itemWithNormalImage:@"btn_back.png" selectedImage:@"btn_back_pressed.png" target:self selector:@selector(backButtonTapped:)]; backBtnImg.position = ccp(45, 286); CCMenu *backBtn = [CCMenu menuWithItems:backBtnImg, nil]; backBtn.position = CGPointZero; [self addChild:backBtn]; EventHandler method (doesn't get called when the scene is re-entered). (void)backButtonTapped:(id)sender { NSLog(@"backButtonTapped\n"); CCMenuItemImage *backButton = (CCMenuItemImage *)sender; [backButton setNormalImage:[CCSprite spriteWithFile:@"btn_back_pressed.png"]]; [[CCDirector sharedDirector] replaceScene:[CCTransitionFade transitionWithDuration:.25 scene:[MenuView scene] withColor:ccBLACK]]; }

  Read the article

• Procedurally generated 2d terrain for side scroller on Sega Genesis hardware?

  - by DJCouchyCouch

  I'm working on the Sega Genesis that has a 8mhz Motorola 68000 CPU. Any ideas on how to generate fast and decent 2d tile terrain for a side scroller in real time? The game would generate new columns or rows depending on the direction the player is scrolling in. The generation would have to be deterministic. The same seed value would generate the same terrain. I'm looking for algorithms that would satisfy the memory and CPU constraints of the hardware.

  Read the article

• Scaling Sound Effects and Physics with Framerate

  - by Thomas Bradsworth

  (I'm using XNA and C#) Currently, my game (a shooter) runs flawlessly with 60 FPS (which I developed around). However, if the framerate is changed, there are two major problems: Gunshot sound effects are slower Jumping gets messed up Here's how I play gunshot sounds: update(gametime) { if(leftMouseButton.down) { enqueueBulletForSend(); playGunShot(); } } Now, obviously, the frequency of playGunShot depends on the framerate. I can easily fix the issue if the FPS is higher than 60 FPS by capping the shooting rate of the gun, but what if the FPS is less than 60? At first I thought to just loop and play more gunshots per frame, but I found that this can cause audio clipping or make the bullets fire in "clumps." Now for the second issue: Here's how jumping works in my game: if(jumpKey.Down && canJump) { velocity.Y += 0.224f; } // ... (other code) ... if(!onGround) velocity.Y += GRAVITY_ACCELERATION * elapsedSeconds; position += velocity; The issue here is that at < 60 FPS, the "intermediate" velocity is lost and therefore the character jumps lower. At 60 FPS, the game adds more "intermediate" velocities, and therefore the character jumps higher. For example, at 60 FPS, the following occurs: Velocity increased to 0.224 Not on ground, so velocity decreased by X Position increased by (0.224 - X) <-- this is the "intermediate" velocity At 30 FPS, the following occurs: Velocity increased to 0.224 Not on ground, so velocity decreased by 2X Position increased by (0.224 - 2X) <-- the "intermediate" velocity was lost All help is appreciated!

  Read the article

• Calculating vertex normals on the GPU

  - by Etan

  I have some height-map sampled on a regular grid stored in an array. Now, I want to use the normals on the sampled vertices for some smoothing algorithm. The way I'm currently doing it is as follows: For each vertex, generate triangles to all it's neighbours. This results in eight neighbours when using the 1-neighbourhood for all vertices except at the borders. +---+---+ ¦ \ ¦ / ¦ +---o---+ ¦ / ¦ \ ¦ +---+---+ For each adjacent triangle, calculate it's normal by taking the cross product between the two distances. As the triangles all have the same size when projected on the xy-plane, I simply average over all eight normals then and store it for this vertex. However, as my data grows larger, this approach takes too much time and I would prefer doing it on the GPU in a shader code. Is there an easy method, maybe if I could store my height-map as a texture?

  Read the article

• Algorithm to shoot at a target in a 3d game

  - by Sebastian Bugiu

  For those of you remembering Descent Freespace it had a nice feature to help you aim at the enemy when shooting non-homing missiles or lasers: it showed a crosshair in front of the ship you chased telling you where to shoot in order to hit the moving target. I tried using the answer from http://stackoverflow.com/questions/4107403/ai-algorithm-to-shoot-at-a-target-in-a-2d-game?lq=1 but it's for 2D so I tried adapting it. I first decomposed the calculation to solve the intersection point for XoZ plane and saved the x and z coordinates and then solving the intersection point for XoY plane and adding the y coordinate to a final xyz that I then transformed to clipspace and put a texture at those coordinates. But of course it doesn't work as it should or else I wouldn't have posted the question. From what I notice the after finding x in XoZ plane and the in XoY the x is not the same so something must be wrong. float a = ENG_Math.sqr(targetVelocity.x) + ENG_Math.sqr(targetVelocity.y) - ENG_Math.sqr(projectileSpeed); float b = 2.0f * (targetVelocity.x * targetPos.x + targetVelocity.y * targetPos.y); float c = ENG_Math.sqr(targetPos.x) + ENG_Math.sqr(targetPos.y); ENG_Math.solveQuadraticEquation(a, b, c, collisionTime); First time targetVelocity.y is actually targetVelocity.z (the same for targetPos) and the second time it's actually targetVelocity.y. The final position after XoZ is crossPosition.set(minTime * finalEntityVelocity.x + finalTargetPos4D.x, 0.0f, minTime * finalEntityVelocity.z + finalTargetPos4D.z); and after XoY crossPosition.y = minTime * finalEntityVelocity.y + finalTargetPos4D.y; Is my approach of separating into 2 planes and calculating any good? Or for 3D there is a whole different approach? sqr() is square not sqrt - avoiding a confusion.

  Read the article

• 2D SAT Collision Detection not working when using certain polygons (With example)

  - by sFuller

  My SAT algorithm falsely reports that collision is occurring when using certain polygons. I believe this happens when using a polygon that does not contain a right angle. Here is a simple diagram of what is going wrong: Here is the problematic code: std::vector<vec2> axesB = polygonB->GetAxes(); //loop over axes B for(int i = 0; i < axesB.size(); i++) { float minA,minB,maxA,maxB; polygonA->Project(axesB[i],&minA,&maxA); polygonB->Project(axesB[i],&minB,&maxB); float intervalDistance = polygonA->GetIntervalDistance(minA, maxA, minB, maxB); if(intervalDistance >= 0) return false; //Collision not occurring } This function retrieves axes from the polygon: std::vector<vec2> Polygon::GetAxes() { std::vector<vec2> axes; for(int i = 0; i < verts.size(); i++) { vec2 a = verts[i]; vec2 b = verts[(i+1)%verts.size()]; vec2 edge = b-a; axes.push_back(vec2(-edge.y,edge.x).GetNormailzed()); } return axes; } This function returns the normalized vector: vec2 vec2::GetNormailzed() { float mag = sqrt( x*x + y*y ); return *this/mag; } This function projects a polygon onto an axis: void Polygon::Project(vec2* axis, float* min, float* max) { float d = axis->DotProduct(&verts[0]); float _min = d; float _max = d; for(int i = 1; i < verts.size(); i++) { d = axis->DotProduct(&verts[i]); _min = std::min(_min,d); _max = std::max(_max,d); } *min = _min; *max = _max; } This function returns the dot product of the vector with another vector. float vec2::DotProduct(vec2* other) { return (x*other->x + y*other->y); } Could anyone give me a pointer in the right direction to what could be causing this bug? Edit: I forgot this function, which gives me the interval distance: float Polygon::GetIntervalDistance(float minA, float maxA, float minB, float maxB) { float intervalDistance; if (minA < minB) { intervalDistance = minB - maxA; } else { intervalDistance = minA - maxB; } return intervalDistance; //A positive value indicates this axis can be separated. } Edit 2: I have recreated the problem in HTML5/Javascript: Demo

  Read the article

• Adding 2D vector movement with rotation applied

  - by Michael Zehnich

  I am trying to apply a slight sine wave movement to objects that float around the screen to make them a little more interesting. I would like to apply this to the objects so that they oscillate from side to side, not front to back (so the oscillation does not affect their forward velocity). After reading various threads and tutorials, I have come to the conclusion that I need to create and add vectors, but I simply cannot come up with a solution that works. This is where I'm at right now, in the object's update method (updated based on comments): Vector2 oldPosition = new Vector2(spritePos.X, spritePos.Y); //note: newPosition is initially set in the constructor to spritePos.x/y Vector2 direction = newPosition - oldPosition; Vector2 perpendicular = new Vector2(direction.Y, -direction.X); perpendicular.Normalize(); sinePosAng += 0.1f; perpendicular.X += 2.5f * (float)Math.Sin(sinePosAng); spritePos.X += velocity * (float)Math.Cos(radians); spritePos.Y += velocity * (float)Math.Sin(radians); spritePos += perpendicular; newPosition = spritePos;

  Read the article

• SRV from UAV on the same texture in directx

  - by notabene

  I'm programming gpgpu raymarching (volumetric raytracing) in directx11. I succesfully perform compute shader and save raymarched volume data to texture. Then i want to use same texture as SRV in normal graphic pipeline. But it doesnt work, texture is not visible. Texture is ok, when i save it file it is what i expect. Texture rendering is ok too, when i render another SRV, it is ok. So problem is only in UAV-SRV. I also triple checked if pointers are ok. Please help, i'm getting mad about this. Here is some code: //before dispatch D3D11_TEXTURE2D_DESC textureDesc; ZeroMemory( &textureDesc, sizeof( textureDesc ) ); textureDesc.Width = xr; textureDesc.Height = yr; textureDesc.MipLevels = 1; textureDesc.ArraySize = 1; textureDesc.SampleDesc.Count = 1; textureDesc.SampleDesc.Quality = 0; textureDesc.Usage = D3D11_USAGE_DEFAULT; textureDesc.BindFlags = D3D11_BIND_UNORDERED_ACCESS | D3D11_BIND_SHADER_RESOURCE ; textureDesc.Format = DXGI_FORMAT_R32G32B32A32_FLOAT; D3D->CreateTexture2D( &textureDesc, NULL, &pTexture ); D3D11_UNORDERED_ACCESS_VIEW_DESC viewDescUAV; ZeroMemory( &viewDescUAV, sizeof( viewDescUAV ) ); viewDescUAV.Format = DXGI_FORMAT_R32G32B32A32_FLOAT; viewDescUAV.ViewDimension = D3D11_UAV_DIMENSION_TEXTURE2D; viewDescUAV.Texture2D.MipSlice = 0; D3DD->CreateUnorderedAccessView( pTexture, &viewDescUAV, &pTextureUAV ); //the getSRV function after dispatch. D3D11_SHADER_RESOURCE_VIEW_DESC srvDesc ; ZeroMemory( &srvDesc, sizeof( srvDesc ) ); srvDesc.Format = DXGI_FORMAT_R32G32B32A32_FLOAT; srvDesc.ViewDimension = D3D11_SRV_DIMENSION_TEXTURE2D; srvDesc.Texture2D.MipLevels = 1; D3DD->CreateShaderResourceView( pTexture, &srvDesc, &pTextureSRV);

  Read the article

• What 2D game engines are there available for C++?

  - by dysoco

  I just realized there are not C++ 2D Game Engines that I know of. For example, something like Pygame in Python, or Slick2D in Java. We have the following: SDL - Too low level, not a Game Engine SFML - Handles more things than SDL and it's more modern, but still not a Game Engine. I like it, but I have found it a little bit buggy with the 2.0 version. Irrlitch - It's a Game Engine, but 3D focused. Ogre3D - Same as Irrlitch Allegro - This is a Game Engine, but it's C based, I'd like a modern C++ library. Monocle Engine - This looks like what I need... but sadly there is no Documentation, no community... nothing, all I have is the Github repo. So, do you know any ? I'd like to use C++, not C#, not Java: I'm just more comfortable with C++.

  Read the article

• 2D Animation Smoothness - Delta time vs. Kinematics

  - by viperld002

  I'm animating a sprite in 2D with key frames of rotation and xy-positions. I've recently had a discussion with someone saying that when the device (happens to be an iPad using cocos2D) hits a performance bump due to whatever else the user may be doing, lag will arise and that the best way to fight it is to not use actual positions, but velocities, accelerations and torques with kinematics. His message is to evaluate the positions and rotations from these speeds at the current point in time. I've never experienced a situation where I've heard of using kinematics to stem lag in 2D animations and am not sure of how effective it could be. Also, it seems to be overkill. The application is not networked so it's all running on a local device. The desired effect is that the animation always plays as closely as it can to the target frame rate. Wouldn't the technique suffer the same problems as just using the time since the last frame or a fixed time step since the kinematics would also require some time value to perform the calculation? What techniques could you suggest to best achieve the desired effect? EDIT 1 Thank you for your responses, they are very illuminating. I want to clarify my question before choosing an answer however, to make sure that this post really serves it's purpose. I have a sprite of a ball, and a text file with 3 arrays worth of information (rotation,translations x, translations y) with each unit of information existing as a key frame to be stepped through (0 to 49 and back to 0 to replay it again). I have this playing by interpolating from the current key frame to the next, every n-units of time. The animation is visibly correct when compared to a video I was given of it, and it is smooth because of the interpolations between the key frames. This is the existing state of the project. There are no physics simulated, only a static animation of a ball moving in a way an artist specifically designed. Should I, instead of rotation in degrees and translations by positions in space, derive velocities, accelerations and torques to express this static animation as a function of time? As in, position now = foo(time now), where foo uses kinematics.

  Read the article

• Good GUI for OpenGL

  - by Cristina

  I am starting to learn OpenGL with FreeGLUT using the Superbible and the knowledge i have from my elementary graphics to brush up on my skills. To get more from this experience i want to integrate a GUI to overwrite the one FreeGLUT uses, now my question is this: is this thing possible and what library should i use? Some characteristics for the library: Open source Multi-platform (Linux and Windows) C/C++ If you have any other recommendations please feel free to post them along with your answers for my problem.

  Read the article

• AndEngine Box2d game

  - by OneMoreVladimir

  I'm developing a 2d survival shooter using Box2d extension and I've got some questions: I have two AnalogOnScreenControls. Their listeners modify both sprites and bodies. I receive TouchEventPool was exhausted and as their number grows the game crashes accidently. I've tried to put the modification of the bodies and sprites on the UpdateThread but that does not solve the problem. What could be the cause? I have a class that at the beginnig of the game loads all the textures. After I relaunch the game activity several times I receive Unable to find Phys Addr for and "green color" interface. But that doesn't happen if I clear the memory manually through the Task Manager before relaunch What could be the cause? I unload my atlas at the end of the game. The game sometimes crashes at start with NullPointerException in onResumeGame. The solution suggested is to set android:configChanges="orientation|screenSize" but my device is API 10 so it doesn't have screenSize property and orientation only does not seem to help, because the game starts in portrait mode at times (though landscape is set in the code)

  Read the article

• Rope Colliding with a Rectangle

  - by Colton

  I have my rope, and I have my rectangles. The rope is similar to the implementation found here: http://nehe.gamedev.net/tutorial/rope_physics/17006/ Now, I want to make the rope properly collide with the rectangle such that the rope will not pass through a rectangle, and wrap around the rectangle and all that good stuff. Currently, I have it set so no rope node can pass through a rect (successfully), however, this means a rope segment can still pass through a block. Ex: So the question is, what can I do to fix this? What I have tried: I create a rectangle between two nodes of a rope, calculate rotation between the nodes, and get myself a transformed rectangle. I can successfully detect a collision between rope segments and a (non-transformed) rectangle. Create a new node or pivot point around the corner of the block, and rearrange nodes to point to the corner node. Trouble is determining what corner the rope segment is passing through. And then the current rope setup goes wonky (based on verlet integration, so a sudden change in position causes the rope to wiggle like a seismograph during a magnitude 8 earth quake.) Among other issues that might be solvable, but its turning into a case by case thing, which doesn't seem right. I think the best answer here would just be a link to a tutorial (I simply can't find any, most lead to box2D or farseer, but I want to at least learn how it works before I hide behind an engine).

  Read the article

• Better way to load level content in XNA?

  - by user2002495

  Currently I loaded all my assets in XNA in the main Game class. What I want to achieve later is that I only load specific assets for specific levels (the game will consist of many levels). Here is how I load my main assets into the main class: protected override void LoadContent() { spriteBatch = new SpriteBatch(GraphicsDevice); plane = new Player(Content.Load<Texture2D>(@"Player/playerSprite"), 6, 8); plane.animation = "down"; plane.pos = new Vector2(400, 500); plane.fps = 15; Global.currentPos = plane.pos; lvl1 = new Level1(Content.Load<Texture2D>(@"Levels/bgLvl1"), Content.Load<Texture2D>(@"Levels/bgLvl1-other"), new Vector2(0, 0), new Vector2(0, -600)); CommonBullet.LoadContent(Content); CommonEnemyBullet.LoadContent(Content); } protected override void UnloadContent() { } protected override void Update(GameTime gameTime) { if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed) this.Exit(); plane.Update(gameTime); lvl1.Update(gameTime); foreach (CommonEnemy ce in cel) { if (ce.CollidesWith(plane)) { ce.hasSpawn = false; } foreach (CommonBullet b in plane.commonBulletList) { if (b.CollidesWith(ce)) { ce.hasSpawn = false; } } ce.Update(gameTime); } LoadCommonEnemy(); base.Update(gameTime); } private void LoadCommonEnemy() { int randY = rand.Next(-600, -10); int randX = rand.Next(0, 750); if (cel.Count < 3) { cel.Add(new CommonEnemy(Content.Load<Texture2D>(@"Enemy/Common/commonEnemySprite"), 7, 2, "left", randX, randY)); } for (int i = 0; i < cel.Count; i++) { if (!cel[i].hasSpawn) { cel.RemoveAt(i); i--; } } } protected override void Draw(GameTime gameTime) { GraphicsDevice.Clear(Color.Black); spriteBatch.Begin(); lvl1.Draw(spriteBatch); plane.Draw(spriteBatch); foreach (CommonEnemy ce in cel) { ce.Draw(spriteBatch); } spriteBatch.End(); base.Draw(gameTime); } I wish to load my players, enemies, all in Level1 class. However, when I move my player & enemy code into the Level1 class, the gameTime returns null. Here is my Level1 class: using System; using System.Collections.Generic; using System.Linq; using System.Text; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Audio; using Microsoft.Xna.Framework.Content; using Microsoft.Xna.Framework.Graphics; using Microsoft.Xna.Framework.Media; using Microsoft.Xna.Framework.Input; using SpaceShooter_Beta.Animation.PlayerCollection; using SpaceShooter_Beta.Animation.EnemyCollection.Common; namespace SpaceShooter_Beta.Levels { public class Level1 { public Texture2D bgTexture1, bgTexture2; public Vector2 bgPos1, bgPos2; public float speed = 5f; Player plane; public Level1(Texture2D texture1, Texture2D texture2, Vector2 pos1, Vector2 pos2) { this.bgTexture1 = texture1; this.bgTexture2 = texture2; this.bgPos1 = pos1; this.bgPos2 = pos2; } public void LoadContent(ContentManager cm) { plane = new Player(cm.Load<Texture2D>(@"Player/playerSprite"), 6, 8); plane.animation = "down"; plane.pos = new Vector2(400, 500); plane.fps = 15; Global.currentPos = plane.pos; } public void Draw(SpriteBatch sb) { sb.Draw(bgTexture1, bgPos1, Color.White); sb.Draw(bgTexture2, bgPos2, Color.White); plane.Draw(sb); } public void Update(GameTime gt) { bgPos1.Y += speed; bgPos2.Y += speed; if (bgPos1.Y >= 600) { bgPos1.Y = -600; } if (bgPos2.Y >= 600) { bgPos2.Y = -600; } plane.Update(gt); } } } Of course when I did this, I delete all my player's code in the main Game class. All of that works fine (no errors) except that the game cannot start. The debugger says that plane.Update(gt); in Level 1 class has null GameTime, same thing with the Draw method in the Level class. Please help, I appreciate for the time. [EDIT] I know that using switch in the main class can be a solution. But I prefer a cleaner solution than that, since using switch still means I need to load all the assets through the main class, the code will be A LOT later on for each levels

  Read the article

< Previous Page | 457 458 459 460 461 462 463 464 465 466 467 468  | Next Page >