Search Results

Search found 25377 results on 1016 pages for 'development'.

Page 408/1016 | < Previous Page | 404 405 406 407 408 409 410 411 412 413 414 415  | Next Page >

• Can anyone explain step-by-step how the as3isolib depth-sorts isometric objects?

  - by Rob Evans

  The library manages to depth-sort correctly, even when using items of non-1x1 sizes. I took a look through the code but it's a big project to go through line by line! There are some questions about the process such as: How are the x, y, z values of each object defined? Are they the center points of the objects or something else? I noticed that the IBounds defines the bounds of the object. If you were to visualise a cuboid of 40, 40, 90 in size, where would each of the IBounds metrics be? I would like to know how as3isolib achieves this although I would also be happy with a generalised pseudo-code version. At present I have a system that works 90% of the time but in cases of objects that are along the same horizontal line, the depth is calculated as the same value. The depth calculation currently works like this: x = object horizontal center point y = object vertical center point originX and Y = the origin point relative to the object so if you want the origin to be the center, the value would be originX = 0.5, originY = 0.5. If you wanted the origin to be vertical center, horizontal far right of the object it would be originX = 1.0, originY = 0.5. The origin adjusts the position that the object is transformed from. AABB_width = The bounding box width. AABB_height = The bounding box height. depth = x + (AABB_width * originX) + y + (AABB_height * originY) - z; This generates the same depth for all objects along the same horizontal x.

  Read the article

• How do I draw a point sprite using OpenGL ES on Android?

  - by nbolton

  Edit: I'm using the GL enum, which is incorrect since it's not part of OpenGL ES (see my answer). I should have used GL10, GL11 or GL20 instead. Here's a few snippets of what I have so far... void create() { renderer = new ImmediateModeRenderer(); tiles = Gdx.graphics.newTexture( Gdx.files.getFileHandle("res/tiles2.png", FileType.Internal), TextureFilter.MipMap, TextureFilter.Linear, TextureWrap.ClampToEdge, TextureWrap.ClampToEdge); } void render() { Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT); Gdx.gl.glClearColor(0.6f, 0.7f, 0.9f, 1); } void renderSprite() { int handle = tiles.getTextureObjectHandle(); Gdx.gl.glBindTexture(GL.GL_TEXTURE_2D, handle); Gdx.gl.glEnable(GL.GL_POINT_SPRITE); Gdx.gl11.glTexEnvi(GL.GL_POINT_SPRITE, GL.GL_COORD_REPLACE, GL.GL_TRUE); renderer.begin(GL.GL_POINTS); renderer.vertex(pos.x, pos.y, pos.z); renderer.end(); } create() is called once when the program starts, and renderSprites() is called for each sprite (so, pos is unique to each sprite) where the sprites are arranged in a sort-of 3D cube. Unfortunately though, this just renders a few white dots... I suppose that the texture isn't being bound which is why I'm getting white dots. Also, when I draw my sprites on anything other than 0 z-axis, they do not appear -- I read that I need to crease my zfar and znear, but I have no idea how to do this using libgdx (perhaps it's because I'm using ortho projection? What do I use instead?). I know that the texture is usable, since I was able to render it using a SpriteBatch, but I guess I'm not using it properly with OpenGL.

  Read the article

• x axis detection issues platformer starter kit

  - by dbomb101

  I've come across a problem with the collision detection code in the platformer starter kit for xna.It will send up the impassible flag on the x axis despite being nowhere near a wall in either direction on the x axis, could someone could tell me why this happens ? Here is the collision method. /// <summary> /// Detects and resolves all collisions between the player and his neighboring /// tiles. When a collision is detected, the player is pushed away along one /// axis to prevent overlapping. There is some special logic for the Y axis to /// handle platforms which behave differently depending on direction of movement. /// </summary> private void HandleCollisions() { // Get the player's bounding rectangle and find neighboring tiles. Rectangle bounds = BoundingRectangle; int leftTile = (int)Math.Floor((float)bounds.Left / Tile.Width); int rightTile = (int)Math.Ceiling(((float)bounds.Right / Tile.Width)) - 1; int topTile = (int)Math.Floor((float)bounds.Top / Tile.Height); int bottomTile = (int)Math.Ceiling(((float)bounds.Bottom / Tile.Height)) - 1; // Reset flag to search for ground collision. isOnGround = false; // For each potentially colliding tile, for (int y = topTile; y <= bottomTile; ++y) { for (int x = leftTile; x <= rightTile; ++x) { // If this tile is collidable, TileCollision collision = Level.GetCollision(x, y); if (collision != TileCollision.Passable) { // Determine collision depth (with direction) and magnitude. Rectangle tileBounds = Level.GetBounds(x, y); Vector2 depth = RectangleExtensions.GetIntersectionDepth(bounds, tileBounds); if (depth != Vector2.Zero) { float absDepthX = Math.Abs(depth.X); float absDepthY = Math.Abs(depth.Y); // Resolve the collision along the shallow axis. if (absDepthY < absDepthX || collision == TileCollision.Platform) { // If we crossed the top of a tile, we are on the ground. if (previousBottom <= tileBounds.Top) isOnGround = true; // Ignore platforms, unless we are on the ground. if (collision == TileCollision.Impassable || IsOnGround) { // Resolve the collision along the Y axis. Position = new Vector2(Position.X, Position.Y + depth.Y); // Perform further collisions with the new bounds. bounds = BoundingRectangle; } } //This is the section which deals with collision on the x-axis else if (collision == TileCollision.Impassable) // Ignore platforms. { // Resolve the collision along the X axis. Position = new Vector2(Position.X + depth.X, Position.Y); // Perform further collisions with the new bounds. bounds = BoundingRectangle; } } } } } // Save the new bounds bottom. previousBottom = bounds.Bottom; }

  Read the article

• 2D Collision masks for handling slopes

  - by JiminyCricket

  I've been looking at the example at: http://create.msdn.com/en-US/education/catalog/tutorial/collision_2d_perpixel and am trying to figure out how to adjust the sprite once a collision has been detected. As David suggested at XNA 4.0 2D sidescroller variable terrain heightmap for walking/collision, I made a few sensor points (feet, sides, bottom center, etc.) and can easily detect when these points actually collide with non-transparent portions of a second texture (simple slope). I'm having trouble with the algorithm of how I would actually adjust the sprite position based on a collision. Say I detect a collision with the slope at the sprite's right foot. How can I scan the slope texture data to find the Y position to place the sprite's foot so it is no longer inside the slope? The way it is stored as a 1D array in the example is a bit confusing, should I try to store the data as a 2D array instead? For test purposes, I'm thinking of just using the slope texture alpha itself as a primitive and easy collision mask (no grass bits or anything besides a simple non-linear slope). Then, as in the example, I find the coordinates of any collisions between the slope texture and the sprite's sensors and mark these special sensor collisions as having occurred. Finally, in the case of moving up a slope, I would scan for the first transparent pixel above (in the texture's Ys at that X) the right foot collision point and set that as the new height of the sprite. I'm a little unclear also on when I should make these adjustments. Collisions are checked on every game.update() so would I quickly change the position of the sprite before the next update is called? I also noticed several people mention that it's best to separate collision checks horizontally and vertically, why is that exactly? Open to any suggestions if this is an inefficient or inaccurate way of handling this. I wish MSDN had provided an example of something like this, I didn't know it would be so much more complex than NES Mario style pure box platforming!

  Read the article

• 2D SAT Collision Detection not working when using certain polygons

  - 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?

  Read the article

• Is there an open source sports manager project?

  - by massive

  For a long time I've tried to search for an open source manager game, but without any luck. I'm looking for a suitable project for a reference to my own pet project. Features like well designed data model, tournament and fixture generation and understandable match simulation algorithm would be a great bonuses. I'm especially interested in game projects like Hattrick and SI Games' Football Manager, although it is irrelevant what the particular sport is. The project should be preferably web-based as Hattrick is. I've crawled through GitHub and SourceForge, but I found only a few sports simulation projects. Projects, which I have found, were either dead or not fulfilling my wishes. Do you know any open source manager game / fantasy sports game project, which would be available as open source, OR at least any material, which would be useful when building a such project?

  Read the article

• Effects to make a speeding spaceship look faster

  - by Badescu Alexandru

  I have a spaceship and I've created a "boost" functionality that speeds up my spaceship, what effects should I implement to create the impression of high speed? I was thinking of making everything except my spaceship blurry but I think there would be something missing. Any ideas? Btw. I am working in XNA C# but if you aren't familiar to XNA describing some effects is still useful. The Game is 3d and i've attached some printscreens of the game This is in normal mode ( none boosted ) and here is the boosted mode ( the craft speeds up forward while the camera speeds in its normal speed , the non boosted speed )

  Read the article

• How was collision detection handled in The Legend of Zelda: A Link to the Past?

  - by Restart

  I would like to know how the collision detection was done in The Legend of Zelda: A Link To The Past. The game is 16x16 tile based, so how did they do the tiles where only a quarter or half of the tile is occupied? Did they use a smaller grid for collision detection like 8x8 tiles, so four of them make one 16x16 tile of the texture grid? But then, they also have true half tiles which are diagonally cut and the corners of the tiles seem to be round or something. If Link walks into tiles corner he can keep on walking and automatically moves around it's corner. How is that done? I hope someone can help me out here.

  Read the article

• Will a polled event system cause lag for a server?

  - by Milo

  I'm using a library called ENet. It is a reliable UDP library. The way it works is a polled event system like this: ENetEvent event; /* Wait up to 1000 milliseconds for an event. */ while (enet_host_service (client, & event, 1000) > 0) { switch (event.type) { case ENET_EVENT_TYPE_CONNECT: printf ("A new client connected from %x:%u.\n", event.peer -> address.host, event.peer -> address.port); /* Store any relevant client information here. */ event.peer -> data = "Client information"; break; case ENET_EVENT_TYPE_RECEIVE: printf ("A packet of length %u containing %s was received from %s on channel %u.\n", event.packet -> dataLength, event.packet -> data, event.peer -> data, event.channelID); /* Clean up the packet now that we're done using it. */ enet_packet_destroy (event.packet); break; case ENET_EVENT_TYPE_DISCONNECT: printf ("%s disconected.\n", event.peer -> data); /* Reset the peer's client information. */ event.peer -> data = NULL; } } It waits up to 1000 milliseconds for an event. If I'm hosting say 75 event driven card games and a lobby on the same thread as this code, will it cause any problems. If my understanding is correct, the process will simply sleep until there is an event, when there is one, it will process the event then come back here where potentially 5 or so events have queued up since so enet_host_services would return right away and not cause lag. I have been advised not to use multiple threads, will that be alright like this? Thanks

  Read the article

• SDL_BlitSurface segmentation fault (surfaces aren't null)

  - by Trollkemada

  My app is crashing on SDL_BlitSurface() and i can't figure out why. I think it has something to do with my static object. If you read the code you'll why I think so. This happens when the limits of the map are reached, i.e. (iwidth || jheight). This is the code: Map.cpp (this render) Tile const * Map::getTyle(int i, int j) const { if (i >= 0 && j >= 0 && i < width && j < height) { return data[i][j]; } else { return &Tile::ERROR_TYLE; // This makes SDL_BlitSurface (called later) crash //return new Tile(TileType::ERROR); // This works with not problem (but is memory leak, of course) } } void Map::render(int x, int y, int width, int height) const { //DEBUG("(Rendering...) x: "<<x<<", y: "<<y<<", width: "<<width<<", height: "<<height); int firstI = x / TileType::PIXEL_PER_TILE; int firstJ = y / TileType::PIXEL_PER_TILE; int lastI = (x+width) / TileType::PIXEL_PER_TILE; int lastJ = (y+height) / TileType::PIXEL_PER_TILE; // The previous integer division rounds down when dealing with positive values, but it rounds up // negative values. This is a fix for that (We need those values always rounded down) if (firstI < 0) { firstI--; } if (firstJ < 0) { firstJ--; } const int firstX = x; const int firstY = y; SDL_Rect srcRect; SDL_Rect dstRect; for (int i=firstI; i <= lastI; i++) { for (int j=firstJ; j <= lastJ; j++) { if (i*TileType::PIXEL_PER_TILE < x) { srcRect.x = x % TileType::PIXEL_PER_TILE; srcRect.w = TileType::PIXEL_PER_TILE - (x % TileType::PIXEL_PER_TILE); dstRect.x = i*TileType::PIXEL_PER_TILE + (x % TileType::PIXEL_PER_TILE) - firstX; } else if (i*TileType::PIXEL_PER_TILE >= x + width) { srcRect.x = 0; srcRect.w = x % TileType::PIXEL_PER_TILE; dstRect.x = i*TileType::PIXEL_PER_TILE - firstX; } else { srcRect.x = 0; srcRect.w = TileType::PIXEL_PER_TILE; dstRect.x = i*TileType::PIXEL_PER_TILE - firstX; } if (j*TileType::PIXEL_PER_TILE < y) { srcRect.y = 0; srcRect.h = TileType::PIXEL_PER_TILE - (y % TileType::PIXEL_PER_TILE); dstRect.y = j*TileType::PIXEL_PER_TILE + (y % TileType::PIXEL_PER_TILE) - firstY; } else if (j*TileType::PIXEL_PER_TILE >= y + height) { srcRect.y = y % TileType::PIXEL_PER_TILE; srcRect.h = y % TileType::PIXEL_PER_TILE; dstRect.y = j*TileType::PIXEL_PER_TILE - firstY; } else { srcRect.y = 0; srcRect.h = TileType::PIXEL_PER_TILE; dstRect.y = j*TileType::PIXEL_PER_TILE - firstY; } SDL::YtoSDL(dstRect.y, srcRect.h); SDL_BlitSurface(getTyle(i,j)->getType()->getSurface(), &srcRect, SDL::getScreen(), &dstRect); // <-- Crash HERE /*DEBUG("i = "<<i<<", j = "<<j); DEBUG("srcRect.x = "<<srcRect.x<<", srcRect.y = "<<srcRect.y<<", srcRect.w = "<<srcRect.w<<", srcRect.h = "<<srcRect.h); DEBUG("dstRect.x = "<<dstRect.x<<", dstRect.y = "<<dstRect.y);*/ } } } Tile.h #ifndef TILE_H #define TILE_H #include "TileType.h" class Tile { private: TileType const * type; public: static const Tile ERROR_TYLE; Tile(TileType const * t); ~Tile(); TileType const * getType() const; }; #endif Tile.cpp #include "Tile.h" const Tile Tile::ERROR_TYLE(TileType::ERROR); Tile::Tile(TileType const * t) : type(t) {} Tile::~Tile() {} TileType const * Tile::getType() const { return type; } TileType.h #ifndef TILETYPE_H #define TILETYPE_H #include "SDL.h" #include "DEBUG.h" class TileType { protected: TileType(); ~TileType(); public: static const int PIXEL_PER_TILE = 30; static const TileType * ERROR; static const TileType * AIR; static const TileType * SOLID; virtual SDL_Surface * getSurface() const = 0; virtual bool isSolid(int x, int y) const = 0; }; #endif ErrorTyle.h #ifndef ERRORTILE_H #define ERRORTILE_H #include "TileType.h" class ErrorTile : public TileType { friend class TileType; private: ErrorTile(); mutable SDL_Surface * surface; static const char * FILE_PATH; public: SDL_Surface * getSurface() const; bool isSolid(int x, int y) const ; }; #endif ErrorTyle.cpp (The surface can't be loaded when building the object, because it is a static object and SDL_Init() needs to be called first) #include "ErrorTile.h" const char * ErrorTile::FILE_PATH = ("C:\\error.bmp"); ErrorTile::ErrorTile() : TileType(), surface(NULL) {} SDL_Surface * ErrorTile::getSurface() const { if (surface == NULL) { if (SDL::isOn()) { surface = SDL::loadAndOptimice(ErrorTile::FILE_PATH); if (surface->w != TileType::PIXEL_PER_TILE || surface->h != TileType::PIXEL_PER_TILE) { WARNING("Bad tile surface size"); } } else { ERROR("Trying to load a surface, but SDL is not on"); } } if (surface == NULL) { // This if doesn't get called, so surface != NULL ERROR("WTF? Can't load surface :\\"); } return surface; } bool ErrorTile::isSolid(int x, int y) const { return true; }

  Read the article

• Coordinate based travel through multi-line path over elapsed time

  - by Chris

  I have implemented A* Path finding to decide the course of a sprite through multiple waypoints. I have done this for point A to point B locations but am having trouble with multiple waypoints, because on slower devices when the FPS slows and the sprite travels PAST a waypoint I am lost as to the math to switch directions at the proper place. EDIT: To clarify my path finding code is separate in a game thread, this onUpdate method lives in a sprite like class which happens in the UI thread for sprite updating. To be even more clear the path is only updated when objects block the map, at any given point the current path could change but that should not affect the design of the algorithm if I am not mistaken. I do believe all components involved are well designed and accurate, aside from this piece :- ) Here is the scenario: public void onUpdate(float pSecondsElapsed) { // this could be 4x speed, so on slow devices the travel moved between // frames could be very large. What happens with my original algorithm // is it will start actually doing circles around the next waypoint.. pSecondsElapsed *= SomeSpeedModificationValue; final int spriteCurrentX = this.getX(); final int spriteCurrentY = this.getY(); // getCoords contains a large array of the coordinates to each waypoint. // A waypoint is a destination on the map, defined by tile column/row. The // path finder converts these waypoints to X,Y coords. // // I.E: // Given a set of waypoints of 0,0 to 12,23 to 23, 0 on a 23x23 tile map, each tile // being 32x32 pixels. This would translate in the path finder to this: // -> 0,0 to 12,23 // Coord : x=16 y=16 // Coord : x=16 y=48 // Coord : x=16 y=80 // ... // Coord : x=336 y=688 // Coord : x=336 y=720 // Coord : x=368 y=720 // // -> 12,23 to 23,0 -NOTE This direction change gives me trouble specifically // Coord : x=400 y=752 // Coord : x=400 y=720 // Coord : x=400 y=688 // ... // Coord : x=688 y=16 // Coord : x=688 y=0 // Coord : x=720 y=0 // // The current update index, the index specifies the coordinate that you see above // I.E. final int[] coords = getCoords( 2 ); -> x=16 y=80 final int[] coords = getCoords( ... ); // now I have the coords, how do I detect where to set the position? The tricky part // for me is when a direction changes, how do I calculate based on the elapsed time // how far to go up the new direction... I just can't wrap my head around this. this.setPosition(newX, newY); }

  Read the article

• Why did the old 3D games have "jittery" graphics?

  - by dreta

  I've been playing MediEvil lately and it got me wondering, what causes some of the old 3D games have "flowing" graphics when moving? It's present in games like Final Fantasy VII, MediEvil, i remember Dungeon Keeper 2 having the same thing in zoom mode, however f.e. Quake 2 didn't have this "issue" and it's just as old. The resolution doesn't seem to be the problem, everything is rendered perfectly fine when you stand still. So is the game refreshing slowly or it's something to do with buffering?

  Read the article

• Protection against CheatEngine and other injectors [duplicate]

  - by Lucas

  This question already has an answer here: Strategies to Defeat Memory Editors for Cheating - Desktop Games 10 answers Is protection against CheatEngine and other inject tools are possible to do? I was thinking a day and the only one idea I've got is about writting some small application which will scan the processes running every second, and in case if any injector will be found the game client will exit immadiately. I'm writing here to see your opinions on this case as some of you may have some expierence against protecting the game clients against DLL or PYC injection or something.

  Read the article

• Android/Java AI agent framework/middleware

  - by corneliu

  I am looking for an AI agent framework to use as a starting point in an Android game I have to create for a university research project. It has been suggested to me to use JADE, but, as far as I can tell, it's not a suitable framework for games (at least for my game idea) because it runs in a split-execution mode, and it needs an always-active network connection to a main host. What I want is just a little something to give me a headstart. I am willing to adjust the game's features to the framework because it's more of a mockup game, and the purpose is to compare the performance of a couple of agents in the game world. The game will be very simplistic, with a minimal UI that displays various stats about the characters in the game (so no graphics, no pathfinding). Thank you.

  Read the article

• Box2D how to implement a camera?

  - by Romeo

  By now i have this Camera class. package GameObjects; import main.Main; import org.jbox2d.common.Vec2; public class Camera { public int x; public int y; public int sx; public int sy; public static final float PIXEL_TO_METER = 50f; private float yFlip = -1.0f; public Camera() { x = 0; y = 0; sx = x + Main.APPWIDTH; sy = y + Main.APPHEIGHT; } public Camera(int x, int y) { this.x = x; this.y = y; sx = x + Main.APPWIDTH; sy = y + Main.APPHEIGHT; } public void update() { sx = x + Main.APPWIDTH; sy = y + Main.APPHEIGHT; } public void moveCam(int mx, int my) { if(mx >= 0 && mx <= 80) { this.x -= 2; } else if(mx <= Main.APPWIDTH && mx >= Main.APPWIDTH - 80) { this.x += 2; } if(my >= 0 && my <= 80) { this.y += 2; } else if(my <= Main.APPHEIGHT && my >= Main.APPHEIGHT - 80) { this.y -= 2; } this.update(); } public float meterToPixel(float meter) { return meter * PIXEL_TO_METER; } public float pixelToMeter(float pixel) { return pixel / PIXEL_TO_METER; } public Vec2 screenToWorld(Vec2 screenV) { return new Vec2(screenV.x + this.x, yFlip * screenV.y + this.y); } public Vec2 worldToScreen(Vec2 worldV) { return new Vec2(worldV.x - this.x, yFlip * worldV.y - this.y); } } I need to know how to modify the screenToWorld and worldToScreen functions to include the PIXEL_TO_METER scaling.

  Read the article

• Unity3D: How to make the camera focus a moving game object with ITween?

  - by nathan

  I'm trying to write a solar system with Unity3D. Planets are sphere game objects rotating around another sphere game object representing the star. What i want to achieve is let the user click on a planet and then zoom the camera on this planet and then make the camera follow and keep it centered on the screen while it keep moving around the star. I decided to use iTween library and so far i was able to create the zoom effect using iTween.MoveUpdate. My problem is that the focused planet does not say properly centered as it moves. Here is the relevant part of my script: void Update () { if (Input.GetButtonDown("Fire1")) { Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition); RaycastHit hit; if (Physics.Raycast(ray, out hit, Mathf.Infinity, concernedLayers)) { selectedPlanet = hit.collider.gameObject; } } } void LateUpdate() { if (selectedPlanet != null) { Vector3 pos = selectedPlanet.transform.position; pos.z = selectedPlanet.transform.position.z - selectedPlanet.transform.localScale.z; pos.y = selectedPlanet.transform.position.y; iTween.MoveUpdate(Camera.main.gameObject, pos, 2); } } What do i need to add to this script to make the selected planet stay centered on the screen? I hosted my current project as a webplayer application so you see what's going wrong. You can access it here.

  Read the article

• Time calculation between openGL update calls.

  - by Vijayendra

  In XNA, the system calls update and draw function with the time information. This contains information such as how much time has passed since last update was called. This makes easy to integrate time and do animation calculation accordingly. But I dont see any such mechanism in openGL. I see openGL requires programmers to have their own implementation which could be buggy or inefficient. Is there any standard (and efficient) code that demonstrate this practice in openGL?

  Read the article

• Problems with 3D Array for Voxel Data

  - by Sean M.

  I'm trying to implement a voxel engine in C++ using OpenGL, and I've been working on the rendering of the world. In order to render, I have a 3D array of uint16's that hold that id of the block at the point. I also have a 3D array of uint8's that I am using to store the visibility data for that point, where each bit represents if a face is visible. I have it so the blocks render and all of the proper faces are hidden if needed, but all of the blocks are offset by a power of 2 from where they are stored in the array. So the block at [0][0][0] is rendered at (0, 0, 0), and the block at 11 is rendered at (1, 1, 1), but the block at [2][2][2] is rendered at (4, 4, 4) and the block at [3][3][3] is rendered at (8, 8, 8), and so on and so forth. This is the result of drawing the above situation: I'm still a little new to the more advanced concepts of C++, like triple pointers, which I'm using for the 3D array, so I think the error is somewhere in there. This is the code for creating the arrays: uint16*** _blockData; //Contains a 3D array of uint16s that are the ids of the blocks in the region uint8*** _visibilityData; //Contains a 3D array of bytes that hold the visibility data for the faces //Allocate memory for the world data _blockData = new uint16**[REGION_DIM]; for (int i = 0; i < REGION_DIM; i++) { _blockData[i] = new uint16*[REGION_DIM]; for (int j = 0; j < REGION_DIM; j++) _blockData[i][j] = new uint16[REGION_DIM]; } //Allocate memory for the visibility _visibilityData = new uint8**[REGION_DIM]; for (int i = 0; i < REGION_DIM; i++) { _visibilityData[i] = new uint8*[REGION_DIM]; for (int j = 0; j < REGION_DIM; j++) _visibilityData[i][j] = new uint8[REGION_DIM]; } Here is the code used to create the block mesh for the region: //Check if the positive x face is visible, this happens for every face //Block::VERT_X_POS is just an array of non-transformed cube verts for one face //These checks are in a triple loop, which goes over every place in the array if (_visibilityData[x][y][z] & 0x01 > 0) { _vertexData->AddData(&(translateVertices(Block::VERT_X_POS, x, y, z)[0]), sizeof(Block::VERT_X_POS)); } //This is a seperate method, not in the loop glm::vec3* translateVertices(const glm::vec3 data[], uint16 x, uint16 y, uint16 z) { glm::vec3* copy = new glm::vec3[6]; memcpy(&copy, &data, sizeof(data)); for(int i = 0; i < 6; i++) copy[i] += glm::vec3(x, -y, z); //Make +y go down instead return copy; } I cannot see where the blocks may be getting offset by more than they should be, and certainly not why the offsets are a power of 2. Any help is greatly appreciated. Thanks.

  Read the article

• How AlphaBlend Blendstate works in XNA 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)

  Read the article

• Examples of good Javascript/HTML5 based games

  - by Zuch

  Now that Flash is largely being replaced with HTML5 elements (video, audio, canvas, etc.) are there any good examples of web-based games built on completely open standards (meaning Javascript, HTML and CSS)? I see a lot of examples of pure HTML5 implementations of what was once only in Flash (like stuff here: http://www.html5rocks.com/) but not many games, a domain which still seem dominated by Flash. I'm curious what's possible and what the limitations are.

  Read the article

• Collisions between moving ball and polygons

  - by miguelSantirso

  I know this is a very typical problem and that there area a lot of similar questions, but I have been looking for a while and I have not found anything that fits what I want. I am developing a 2D game in which I need to perform collisions between a ball and simple polygons. The polygons are defined as an array of vertices. I have implemented the collisions with the bounding boxes of the polygons (that was easy) and I need to refine that collision in the cases where the ball collides with the bounding box. The ball can move quite fast and the polygons are not too big so I need to perform continuous collisions. I am looking for a method that allows me to detect if the ball collides with a polygon and, at the same time, calculate the new direction for the ball after bouncing in the polygon. (I am using XNA, in case that helps)

  Read the article

• Having trouble with projection matrix, need help

  - by Mr.UNOwen

  I'm having trouble with what appears to be the projection matrix. Given a wide enough of a screen, when a cube is on the left and right most edge, the left or right wall will appear stretched to the point that the front face is 1/10 the width of the side. So I do update the screen ratio along with the projection matrix and view port on screen resize, am I safe to assume all the trouble is from the matrix class? Also the cube follows the mouse, but it's only vertically aligned and ahead of the mouse when going left or right from the center of the screen. Perspective function call: * setPerspective * * @param fov: angle in radians * @param aspect: screen ratio w/h * @param near: near distance * @param far: far distance **/ void APCamera::setPerspective(GMFloat_t fov, GMFloat_t aspect, GMFloat_t near, GMFloat_t far) { GMFloat_t difZ = near - far; GMFloat_t *data; mProjection->clear(); //set to identity matrix data = mProjection->getData(); GMFloat_t v = 1.0f / tan(fov / 2.0f); data[_AP_MAA] = v / aspect; data[_AP_MBB] = v; data[_AP_MCC] = (far + near) / difZ; data[_AP_MCD] = -1.0f; data[_AP_MDD] = 0.0f; data[_AP_MDC] = 2.0f * far * near/ difZ; mRatio = aspect; mInvProjOutdated = true; mIsPerspective = true; } and... #define _AP_MAA 0 #define _AP_MAB 1 #define _AP_MAC 2 #define _AP_MAD 3 #define _AP_MBA 4 #define _AP_MBB 5 #define _AP_MBC 6 #define _AP_MBD 7 #define _AP_MCA 8 #define _AP_MCB 9 #define _AP_MCC 10 #define _AP_MCD 11 #define _AP_MDA 12 #define _AP_MDB 13 #define _AP_MDC 14 #define _AP_MDD 15

  Read the article

• What's the most efficient way to find barycentric coordinates?

  - by bobobobo

  In my profiler, finding barycentric coordinates is apparently somewhat of a bottleneck. I am looking to make it more efficient. It follows the method in shirley, where you compute the area of the triangles formed by embedding the point P inside the triangle. Code: Vector Triangle::getBarycentricCoordinatesAt( const Vector & P ) const { Vector bary ; // The area of a triangle is real areaABC = DOT( normal, CROSS( (b - a), (c - a) ) ) ; real areaPBC = DOT( normal, CROSS( (b - P), (c - P) ) ) ; real areaPCA = DOT( normal, CROSS( (c - P), (a - P) ) ) ; bary.x = areaPBC / areaABC ; // alpha bary.y = areaPCA / areaABC ; // beta bary.z = 1.0f - bary.x - bary.y ; // gamma return bary ; } This method works, but I'm looking for a more efficient one!

  Read the article

• Pixel alignment algorithm

  - by user42325

  I have a set of square blocks, I want to draw them in a window. I am sure the coordinates calculation is correct. But on the screen, some squares' edge overlap with other, some are not. I remember the problem is caused by accuracy of pixels. I remember there's a specific topic related to this kind of problem in 2D image rendering. But I don't remember what exactly it is, and how to solve it. Look at this screenshot. Each block should have a fixed width margin. But in the image, the vertical white line have different width.Though, the horizontal lines looks fine.

  Read the article

• What is wrong with my specular phong shading

  - by Thijser

  I'm sorry if this should be placed on stackoverflow instead however seeing as this is graphics related I was hoping you guys could help me: I'm attempting to write a phong shader and currently working on the specular. I came acros the following formula: base*pow(dot(V,R),shininess) and attempted to implement it (V is the posion of the viewer and R the reflective vector). This gave the following result and code: Vec3Df phongSpecular(const Vec3Df & vertexPos, Vec3Df & normal, const Vec3Df & lightPos, const Vec3Df & cameraPos, unsigned int index) { Vec3Df relativeLightPos=(lightPos-vertexPos); relativeLightPos.normalize(); Vec3Df relativeCameraPos= (cameraPos-vertexPos); relativeCameraPos.normalize(); int DotOfNormalAndLight = Vec3Df::dotProduct(normal,relativeLightPos); Vec3Df reflective =(relativeLightPos-(2*DotOfNormalAndLight*normal))*-1; reflective.normalize(); float phongyness= Vec3Df::dotProduct(reflective,relativeCameraPos); if (phongyness<0){ phongyness=0; } float shininess= Shininess[index]; float speculair = powf(phongyness,shininess); return Ks[index]*speculair; } I'm looking for something more like this:

  Read the article

< Previous Page | 404 405 406 407 408 409 410 411 412 413 414 415  | Next Page >