Search Results

Search found 25496 results on 1020 pages for 'monotouch development'.

Page 521/1020 | < Previous Page | 517 518 519 520 521 522 523 524 525 526 527 528  | Next Page >

• How can I imitate interaction and movement in Diablo II?

  - by user422318

  I'm prototyping a simple browser-based game. It's played from a top down perspective on a 2d canvas. You left-click on a point on the map, and your character will begin walking to it. If you click on a different point on the map, then your character will begin walking to the new point. It's similar to Diablo II: http://www.youtube.com/watch?v=EvDKt-To6K0&feature=related How can I best imitate this movement system for a player? Ideas... Track current coords and target coords If target coords are exactly up, left, right, or down, then increment appropriate direction until you get there Implied else: target coords are in a quadrant. To make this movement look natural, character will have to move diagonally. For example, pretend the target is to the northeast. For each game frame, alternate incrementing current coordinates in the north and then east directions.

  Read the article

• Are these non-standard applications of rendering practical in games?

  - by maul

  I've recently got into 3D and I came up with a few different "tricky" rendering techniques. Unfortunately I don't have the time to work on this myself, but I'd like to know if these are known methods and if they can be used in practice. Hybrid rendering Now I know that ray-tracing is still not fast enough for real-time rendering, at least on home computers. I also know that hybrid rendering (a combination of rasterization and ray-tracing) is a well known theory. However I had the following idea: one could separate a scene into "important" and "not important" objects. First you render the "not important" objects using traditional rasterization. In this pass you also render the "important" objects using a special shader that simply marks these parts on the image using a special color, or some stencil/depth buffer trickery. Then in the second pass you read back the results of the first pass and start ray tracing, but only from the pixels that were marked by the "important" object's shader. This would allow you to only ray-trace exactly what you need to. Could this be fast enough for real-time effects? Rendered physics I'm specifically talking about bullet physics - intersection of a very small object (point/bullet) that travels across a straight line with other, relatively slow-moving, fairly constant objects. More specifically: hit detection. My idea is that you could render the scene from the point of view of the gun (or the bullet). Every object in the scene would draw a different color. You only need to render a 1x1 pixel window - the center of the screen (again, from the gun's point of view). Then you simply check that central pixel and the color tells you what you hit. This is pixel-perfect hit detection based on the graphical representation of objects, which is not common in games. Afaik traditional OpenGL "picking" is a similar method. This could be extended in a few ways: For larger (non-bullet) objects you render a larger portion of the screen. If you put a special-colored plane in the middle of the scene (exactly where the bullet will be after the current frame) you get a method that works as the traditional slow-moving iterative physics test as well. You could simulate objects that the bullet can pass through (with decreased velocity) using alpha blending or some similar trick. So are these techniques in use anywhere, and/or are they practical at all?

  Read the article

• Do I need the 'w' component in my Vector class?

  - by bobobobo

  Assume you're writing matrix code that handles rotation, translation etc for 3d space. Now the transformation matrices have to be 4x4 to fit the translation component in. However, you don't actually need to store a w component in the vector do you? Even in perspective division, you can simply compute and store w outside of the vector, and perspective divide before returning from the method. For example: // post multiply vec2=matrix*vector Vector operator*( const Matrix & a, const Vector& v ) { Vector r ; // do matrix mult r.x = a._11*v.x + a._12*v.y ... real w = a._41*v.x + a._42*v.y ... // perspective divide r /= w ; return r ; } Is there a point in storing w in the Vector class?

  Read the article

• How does a single programmer make a game?

  - by Mike

  I have always been a software developer, but lately I've been wanting to get into games. The only thing stopping me is the fact that I'm a programmer, not an artist. I've made some simple stuff, Tetris, 2D chess things like that but I can't do much art and that's really what holds me back. Now the problem is, I've yet to go to college so most commercial projects wouldn't accept me even to work for free and learn a bit especially with my lack of experience in games and any indie projects I've looked into really have an issue with responding to people interested, or actually completing (or starting really, most don't get past the ideas on paper) the project they want to do. I've looked around locally for artists, anyone who can do modeling, textures or animating or even anyone with some ability to make some more advanced 2D assets to get something like a side-scrolling RPG or something but haven't been able to find anyone. So how do you guys do it? Do I really just have to wait until I can go to college to see if I like working with games or is there some way I can get art (for free, anything I do is just going to be for fun so I don't want to have to sink money into it) and just start messing around on my own? Or am I just having bad luck and not looking in the right places for other people interested in having me help? I'm not looking for anything in particular, just something to fill some time with and see if I like making games. If not, well I'll go back to my software projects. I just have one more year of highschool and I'd like to try a few different areas before I go to college.

  Read the article

• Whole continent simulation [on hold]

  - by user2309021

  Let's suppose I am planning to create a simulation of an entire continent at some point in the past (let's say, around 0 A.D). Is it feasible to spawn a hundred million actors that interact with each other and their environments? Having them reproduce, extract resources, etc? The fact is that I actually want to create a simulation that allows me to zoom in from a view of the entire continent up to a single village, and interact with it. (Think as if you could keep zooming in the campaign map of any Total War game and the transition to the battle map was seamless, not a change of the "game mode"). By the way, I have never made a game in my entire life (I have programmed normal desktop applications, though), so I am really having trouble wrapping my head around how to implement such a thing. Even while thinking about how to implement a simple population simulator, without a graphical interface, I think that the O(n) complexity of traversing an array and telling all people to get one year older each time the program ticks is kind of stupid. Any kind help would be greatly appreciated :) EDIT: After being put on hold, I shall specify a question. How would you implement a simulation of all basic human dynamics (reproduction, resource consumption) in an entire continent (with millions of people)?

  Read the article

• Pseudo-magnet implementation with chipmunk

  - by Eimantas

  How should I go about implementing "natural" magnet on a certain body in chipmunk space? Context is of simple bodies lying in the space (think chessboard). When one of the figures is activated as a magnet - others should start moving towards it. Currently I'm applying force (cpBodyApplyForce)to the other figures with vector calculated towards the activated figure. However this doesn't really feel "natural". Are there any known algorithms for imitating magnets?

  Read the article

• Component based design, but components rely on eatchother

  - by MintyAnt

  I've begun stabbing at a "Component Based" game system. Basically, each entity holds a list of components to update (and render) I inherit the "Component" class and break each game system into it. Examples: RenderComponent - Draws the entity MovementComponent - Moves the entity, deals with velocity and speed checks DamageComponent - Deals with how/if the entity gets damaged... So. My system has this: MovementComponent InputComponent Now maybe my design is off, but the InputComponent should say things like if (w key is down) add y speed to movement if (x key is down) Trigger primary attack This means that the InputComponent sort of relies on these other components. I have to do something alone the lines of: if (w key is down) { MovementComponent* entityMovement = mEntity->GetMovement(); if (entityMovement != NULL) add y speed to movement } which seems kinda crappy every update. Other options? Better design? Is this the best way? Thanks!

  Read the article

• XNA 4: RenderTarget2D textures getting transparent on fullscreen

  - by Shashwat

  I'm generating a Texture2D object using RenderTarget2D as in the following code public static Texture2D GetTextTexture(string text, Vector2 position, SpriteFont font, Color foreColor, Color backColor, Texture2D background=null) { int width = (int)font.MeasureString(text).X; int height = (int)font.MeasureString(text).Y; GraphicsDevice device = Settings.game.GraphicsDevice; SpriteBatch spriteBatch = Settings.game.spriteBatch; RenderTarget2D renderTarget = new RenderTarget2D(device, width, height, false, SurfaceFormat.Color, DepthFormat.Depth24Stencil8, device.PresentationParameters.MultiSampleCount, RenderTargetUsage.DiscardContents); device.SetRenderTarget(renderTarget); device.Clear(backColor); spriteBatch.Begin(SpriteSortMode.Immediate, BlendState.Opaque); if (background != null) spriteBatch.Draw(background, new Rectangle(0, 0, 70, 70), Color.White); spriteBatch.End(); spriteBatch.Begin(); spriteBatch.DrawString(font, text, position, foreColor, 0, new Vector2(0), 0.8f, SpriteEffects.None, 0); spriteBatch.End(); device.SetRenderTarget(null); ResetGraphicsDeviceSettings(); return (Texture2D)renderTarget; } It's working all fine. But when I ToggleFullScreen() (and vice-versa), the previous textures are getting transparent. However, the new textures after that are being generated correctly. What can be the reason for this?

  Read the article

• How can I get a 2D texture to rotate like a compass in XNA?

  - by IronGiraffe

  I'm working on a small maze puzzle game and I'm trying to add a compass to make it somewhat easier for the player to find their way around the maze. The problem is: I'm using XNA's draw method to rotate the arrow and I don't really know how to get it to rotate properly. What I need it to do is point towards the exit from the player's position, but I'm not sure how I can do that. So does anyone know how I can do this? Is there a better way to do it?

  Read the article

• Can I name a team with the name of their city to avoid trademark issues?

  - by Paul

  I was wondering, if you want to make a NBA game on smartphones, without the license held by EA, the first solution seems to name your teams with a different name, such as "Chicragro Brulls" (this is just for the example), but would it be possible to just call your team with the name of the city, such as "Chicago vs. Dallas" ? I know the first solution was chosen by Pro Evolution Soccer, would you know any other game that don't use a license?

  Read the article

• Box2Dweb very slow on node.js

  - by Peteris

  I'm using Box2Dweb on node.js. I have a rotated box object that I apply an impulse to move around. The timestep is set at 50ms, however, it bumps up to 100ms and even 200ms as soon as I add any more edges or boxes. Here are the edges I would like to use as bounds around the playing area: // Computing the corners var upLeft = new b2Vec2(0, 0), lowLeft = new b2Vec2(0, height), lowRight = new b2Vec2(width, height), upRight = new b2Vec2(width, 0) // Edges bounding the visible game area var edgeFixDef = new b2FixtureDef edgeFixDef.friction = 0.5 edgeFixDef.restitution = 0.2 edgeFixDef.shape = new b2PolygonShape var edgeBodyDef = new b2BodyDef; edgeBodyDef.type = b2Body.b2_staticBody edgeFixDef.shape.SetAsEdge(upLeft, lowLeft) world.CreateBody(edgeBodyDef).CreateFixture(edgeFixDef) edgeFixDef.shape.SetAsEdge(lowLeft, lowRight) world.CreateBody(edgeBodyDef).CreateFixture(edgeFixDef) edgeFixDef.shape.SetAsEdge(lowRight, upRight) world.CreateBody(edgeBodyDef).CreateFixture(edgeFixDef) edgeFixDef.shape.SetAsEdge(upRight, upLeft) world.CreateBody(edgeBodyDef).CreateFixture(edgeFixDef) Can box2d really become this slow for even two bodies or is there some pitfall? It would be very surprising given all the demos which successfully use tens of objects.

  Read the article

• Direct3D - Zooming into Mouse Position

  - by roohan

  I'm trying to implement my camera class for a simulation. But I cant figure out how to zoom into my world based on the mouse position. I mean the object under the mouse cursor should remain at the same screen position. My zooming looks like this: VOID ZoomIn(D3DXMATRIX& WorldMatrix, FLOAT const& MouseX, FLOAT const& MouseY) { this->Position.z = this->Position.z * 0.9f; D3DXMatrixLookAtLH(&this->ViewMatrix, &this->Position, &this->Target, &this->UpDirection); } I passed the world matrix to the function because I had the idea to move my drawing origin according to the mouse position. But I cant find out how to calculate the offset in to move my drawing origin. Anyone got an idea how to calculate this? Thanks in advance. SOLVED Ok I solved my problem. Here is the code if anyone is interested: VOID CAMERA2D::ZoomIn(FLOAT const& MouseX, FLOAT const& MouseY) { // Get the setting of the current view port. D3DVIEWPORT9 ViewPort; this->Direct3DDevice->GetViewport(&ViewPort); // Convert the screen coordinates of the mouse to world space coordinates. D3DXVECTOR3 VectorOne; D3DXVECTOR3 VectorTwo; D3DXVec3Unproject(&VectorOne, &D3DXVECTOR3(MouseX, MouseY, 0.0f), &ViewPort, &this->ProjectionMatrix, &this->ViewMatrix, &WorldMatrix); D3DXVec3Unproject(&VectorTwo, &D3DXVECTOR3(MouseX, MouseY, 1.0f), &ViewPort, &this->ProjectionMatrix, &this->ViewMatrix, &WorldMatrix); // Calculate the resulting vector components. float WorldZ = 0.0f; float WorldX = ((WorldZ - VectorOne.z) * (VectorTwo.x - VectorOne.x)) / (VectorTwo.z - VectorOne.z) + VectorOne.x; float WorldY = ((WorldZ - VectorOne.z) * (VectorTwo.y - VectorOne.y)) / (VectorTwo.z - VectorOne.z) + VectorOne.y; // Move the camera into the screen. this->Position.z = this->Position.z * 0.9f; D3DXMatrixLookAtLH(&this->ViewMatrix, &this->Position, &this->Target, &this->UpDirection); // Calculate the world space vector again based on the new view matrix, D3DXVec3Unproject(&VectorOne, &D3DXVECTOR3(MouseX, MouseY, 0.0f), &ViewPort, &this->ProjectionMatrix, &this->ViewMatrix, &WorldMatrix); D3DXVec3Unproject(&VectorTwo, &D3DXVECTOR3(MouseX, MouseY, 1.0f), &ViewPort, &this->ProjectionMatrix, &this->ViewMatrix, &WorldMatrix); // Calculate the resulting vector components. float WorldZ2 = 0.0f; float WorldX2 = ((WorldZ2 - VectorOne.z) * (VectorTwo.x - VectorOne.x)) / (VectorTwo.z - VectorOne.z) + VectorOne.x; float WorldY2 = ((WorldZ2 - VectorOne.z) * (VectorTwo.y - VectorOne.y)) / (VectorTwo.z - VectorOne.z) + VectorOne.y; // Create a temporary translation matrix for calculating the origin offset. D3DXMATRIX TranslationMatrix; D3DXMatrixIdentity(&TranslationMatrix); // Calculate the origin offset. D3DXMatrixTranslation(&TranslationMatrix, WorldX2 - WorldX, WorldY2 - WorldY, 0.0f); // At the offset to the cameras world matrix. this->WorldMatrix = this->WorldMatrix * TranslationMatrix; } Maybe someone has even a better solution than mine.

  Read the article

• LWJGL GL_QUADS texture artifact

  - by Dajgoro Labinac

  I managed to get working lwjgl in Java, and i loaded a test image(tv test card), but i keep getting weird artifacts outside the image. Image link: http://tinypic.com/r/vhv9g/6 Code: glBegin(GL_QUADS); glTexCoord2f(0, 0); glVertex2i(10, 10); glTexCoord2f(1, 0); glVertex2i(500, 10); glTexCoord2f(1, 1); glVertex2i(500, 500); glTexCoord2f(0, 1); glVertex2i(10, 500); glEnd(); What could be the cause?

  Read the article

• Random enemy placement on a 2d grid

  - by Robb

  I want to place my items and enemies randomly (or as randomly as possible). At the moment I use XNA's Random class to generate a number between 800 for X and 600 for Y. It feels like enemies spawn more towards the top of the map than in the middle or bottom. I do not seed the generator, maybe that is something to consider. Are there other techniques described that can improve random enemy placement on a 2d grid?

  Read the article

• android shut-down errors / thread problems

  - by iQue

  Im starting to deal with some stuff in my game that I thought were "minor problems" and one of these are that I get an error every time I shut down my game that looks like this: 09-05 21:40:58.320: E/AndroidRuntime(30401): FATAL EXCEPTION: Thread-4898 09-05 21:40:58.320: E/AndroidRuntime(30401): java.lang.NullPointerException 09-05 21:40:58.320: E/AndroidRuntime(30401): at nielsen.happy.shooter.MainGamePanel.render(MainGamePanel.java:94) 09-05 21:40:58.320: E/AndroidRuntime(30401): at nielsen.happy.shooter.MainThread.run(MainThread.java:101) on these lines is my GameViews rendering-method and the line in my Thread that calls my GameViews rendering-method. Im guessing Something in my surfaceDestroyed(SurfaceHolder holder) is wrong, or maybe Im not ending the tread in the right place. My surfaceDestroyed-method: public void surfaceDestroyed(SurfaceHolder holder) { Log.d(TAG, "Surface is being destroyed"); boolean retry = true; ((MainThread)thread).setRunning(false); while (retry) { try { ((MainThread)thread).join(); retry = false; } catch (InterruptedException e) { } } Log.d(TAG, "Thread was shut down cleanly"); } Also, In my activity for this View my onPaus, onDestoy and onStop are empty, do I maybe need to add something there? The crash occurs when I press my home-button on the phone, or any other button that makes the game stop. But as I understand it the onPaus is called when you press the Home-button.. This is really new territory for me so Im sorry if im missing something obvious or something really big. adding my surfaceCreated method asweel since that is where I start this thread: public void surfaceCreated(SurfaceHolder holder) { controls = new GameControls(this); setOnTouchListener(controls); timer1.schedule(new Task(this), 0, delay1); thread.setRunning(true); thread.start(); } and aslong as this is running, my game is rendering and updating.

  Read the article

• Mouse pointer position to screen space

  - by Ylisar

  If I have a mouse pointer position in pixels of canvas, I can easily convert it to the -1..1 range for both X & Y by lerping by dividing with canvas dimensions. However, the problem is what I should put in Z & W if I want my screen space position to be on the near plane? The step afterwards would be for me to multiply by the inverse of view-projection to take me to world space, where I easily can construct a ray from the cameras world space position.

  Read the article

• Speed up content loading

  - by user1806687

  I am using WinForms Sample downloaded from microsoft website. The problem is, that the model loading time is quite long, using: contentBuilder.Add(ModelPath, ModelName, null, "ModelProcessor"); contentManager.Load<Model>(ModelName); even a simple model, such as a cube with no textures, takes 4+ seconds to load. Now, I am no expert on this, but is there anyway to decrease loading time? EDIT: I've gone thru the code and found out that calling contentBuilder.Build(); ,which comes right after contentBuilder.Add() method takes up most of the time.

  Read the article

• Which API for cross platform mobile audio?

  - by deft_code

  This question focuses on the API's available on phones. I'd been planning to use OpenAL in my game for maximum portability. It runs great on Linux so I can quickly develop the Game and leverage it's superior debugging tools. However I've recently heard that Android doesn't support OpenAL well. Instead they've gone with a OpenSL ES library. What I'm looking for is a free Audio library that I can use with minimal custom code on iPhone, Android, and my Linux desktop. Does such an API exists? Some extra details: The game is written in C++ with custom minimal front ends. ObjC for iPhone, Java for Android, and SFML for Desktops. I'm using OpenGL ES for portability as iPhone doesn't support the more advanced OpenGL APIs.

  Read the article

• Why wont the LibGDX's main class Initialize on Android Launcher?

  - by BluFire

  So I was searching for different ways that could suit me in programming and came across LibGDX. Naturally I looked at the tutorial. As I was doing it, I was following the steps word for word, except naming the classes. In the end, I was able to create the desktop launcher for the game but not the android launcher. The following error is my error: Cannot instantiate the type Game (Game is the name of the class) I got the tutorial from http://steigert.blogspot.com.au/2012/02/1-libgdx-tutorial-introduction.html The link in the tutorial is the original but it uses jogl instead of lwjgl.

  Read the article

• Information about rendering, batches, the graphical card, performance etc. + XNA?

  - by Aidiakapi

  I know the title is a bit vague but it's hard to describe what I'm really looking for, but here goes. When it comes to CPU rendering, performance is mostly easy to estimate and straightforward, but when it comes to the GPU due to my lack of technical background information, I'm clueless. I'm using XNA so it'd be nice if theory could be related to that. So what I actually wanna know is, what happens when and where (CPU/GPU) when you do specific draw actions? What is a batch? What influence do effects, projections etc have? Is data persisted on the graphics card or is it transferred over every step? When there's talk about bandwidth, are you talking about a graphics card internal bandwidth, or the pipeline from CPU to GPU? Note: I'm not actually looking for information on how the drawing process happens, that's the GPU's business, I'm interested on all the overhead that precedes that. I'd like to understand what's going on when I do action X, to adapt my architectures and practices to that. Any articles (possibly with code examples), information, links, tutorials that give more insight in how to write better games are very much appreciated. Thanks :)

  Read the article

• How to set sprite source coordinates?

  - by ChaosDev

  I am creating own sprite drawer with DX11 on C++. Works fine but I dont know how to apply source rectangle to texture coordinates of rendering surface(for animation sprite sheets) //source = (0,0,32,64); //RECT D3DXVECTOR2 t0 = D3DXVECTOR2( 1.0f, 0.0f); D3DXVECTOR2 t1 = D3DXVECTOR2( 1.0f, 1.0f); D3DXVECTOR2 t2 = D3DXVECTOR2( 0.0f, 1.0f); D3DXVECTOR2 t3 = D3DXVECTOR2( 0.0f, 1.0f); D3DXVECTOR2 t4 = D3DXVECTOR2( 0.0f, 0.0f); D3DXVECTOR2 t5 = D3DXVECTOR2( 1.0f, 0.0f); VertexPositionColorTexture vertices[] = { { D3DXVECTOR3( dest.left+dest.right, dest.top, z),D3DXVECTOR4(1,1,1,1), t0}, { D3DXVECTOR3( dest.left+dest.right, dest.top+dest.bottom, z),D3DXVECTOR4(1,1,1,1), t1}, { D3DXVECTOR3( dest.left, dest.top+dest.bottom, z),D3DXVECTOR4(1,1,1,1), t2}, { D3DXVECTOR3( dest.left, dest.top+dest.bottom, z),D3DXVECTOR4(1,1,1,1), t3}, { D3DXVECTOR3( dest.left , dest.top, z),D3DXVECTOR4(1,1,1,1), t4}, { D3DXVECTOR3( dest.left+dest.right, dest.top, z),D3DXVECTOR4(1,1,1,1), t5}, };

  Read the article

• How can I cleanly and elegantly handle data and dependancies between classes

  - by Neophyte

  I'm working on 2d topdown game in SFML 2, and need to find an elegant way in which everything will work and fit together. Allow me to explain. I have a number of classes that inherit from an abstract base that provides a draw method and an update method to all the classes. In the game loop, I call update and then draw on each class, I imagine this is a pretty common approach. I have classes for tiles, collisions, the player and a resource manager that contains all the tiles/images/textures. Due to the way input works in SFML I decided to have each class handle input (if required) in its update call. Up until now I have been passing in dependencies as needed, for example, in the player class when a movement key is pressed, I call a method on the collision class to check if the position the player wants to move to will be a collision, and only move the player if there is no collision. This works fine for the most part, but I believe it can be done better, I'm just not sure how. I now have more complex things I need to implement, eg: a player is able to walk up to an object on the ground, press a key to pick it up/loot it and it will then show up in inventory. This means that a few things need to happen: Check if the player is in range of a lootable item on keypress, else do not proceed. Find the item. Update the sprite texture on the item from its default texture to a "looted" texture. Update the collision for the item: it might have changed shape or been removed completely. Inventory needs to be updated with the added item. How do I make everything communicate? With my current system I will end up with my classes going out of scope, and method calls to each other all over the place. I could tie up all the classes in one big manager and give each one a reference to the parent manager class, but this seems only slightly better. Any help/advice would be greatly appreciated! If anything is unclear, I'm happy to expand on things.

  Read the article

• Are there any reasons to use Legacy (2.X) OpenGL?

  - by user27886

  The benefits are well documented of the Modern OpenGL 3.X & 4.X API's, but I'm wondering if there are ANY benefits to keeping with the old OpenGL, Or if learning OpenGL 2.X is a complete waste of time now no matter what? Particularly I've wondered if using the OpenGL 2.X API is appropriate if the target platform had graphics hardware capable of only up to OpenGL 2.X. Would a driver update on said target platform allow programs compiled using the Modern OpenGL API's to be released on this old platform? If they both work, which would be faster? Thanks

  Read the article

• In 3D camera math, calculate what Z depth is pixel unity for a given FOV

  - by badweasel

  I am working in iOS and OpenGL ES 2.0. Through trial and error I've figured out a frustum to where at a specific z depth pixels drawn are 1 to 1 with my source textures. So 1 pixel in my texture is 1 pixel on the screen. For 2d games this is good. Of course it means that I also factor in things like the size of the quad and the size of the texture. For example if my sprite is a quad 32x32 pixels. The quad size is 3.2 units wide and tall. And the texcoords are 32 / the size of the texture wide and tall. Then the frustum is: matrixFrustum(-(float)backingWidth/frustumScale,(float)backingWidth/frustumScale, -(float)backingHeight/frustumScale, (float)backingHeight/frustumScale, 40, 1000, mProjection); Where frustumScale is 800 for a retina screen. Then at a distance of 800 from camera the sprite is pixel for pixel the same as photoshop. For 3d games sometimes I still want to be able to do this. But depending on the scene I sometimes need the FOV to be different things. I'm looking for a way to figure out what Z depth will achieve this same pixel unity for a given FOV. For this my mProjection is set using: matrixPerspective(cameraFOV, near, far, (float)backingWidth / (float)backingHeight, mProjection); With testing I found that at an FOV of 45.0 a Z of 38.5 is very close to pixel unity. And at an FOV of 30.0 a Z of 59.5 is about right. But how can I calculate a value that is spot on? Here's my matrixPerspecitve code: void matrixPerspective(float angle, float near, float far, float aspect, mat4 m) { //float size = near * tanf(angle / 360.0 * M_PI); float size = near * tanf(degreesToRadians(angle) / 2.0); float left = -size, right = size, bottom = -size / aspect, top = size / aspect; // Unused values in perspective formula. m[1] = m[2] = m[3] = m[4] = 0; m[6] = m[7] = m[12] = m[13] = m[15] = 0; // Perspective formula. m[0] = 2 * near / (right - left); m[5] = 2 * near / (top - bottom); m[8] = (right + left) / (right - left); m[9] = (top + bottom) / (top - bottom); m[10] = -(far + near) / (far - near); m[11] = -1; m[14] = -(2 * far * near) / (far - near); } And my mView is set using: lookAtMatrix(cameraPos, camLookAt, camUpVector, mView); * UPDATE * I'm going to leave this here in case anyone has a different solution, can explain how they do it, or why this works. This is what I figured out. In my system I use a 10th scale unit to pixels on non-retina displays and a 20th scale on retina displays. The iPhone is 640 pixels wide on retina and 320 pixels wide on non-retina (obsolete). So if I want something to be the full screen width I divide by 20 to get the OpenGL unit width. Then divide that by 2 to get the left and right unit position. Something 32 units wide centered on the screen goes from -16 to +16. Believe it or not I have an excel spreadsheet do all this math for me and output all the vertex data for my sprite sheet. It's an arbitrary thing I made up to do .1 units = 1 non-retina pixel or 2 retina pixels. I could have made it .01 units = 2 pixels and someday I might switch to that. But for now it's the other. So the width of the screen in units is 32.0, and that means the left most pixel is at -16.0 and the right most is at 16.0. After messing a bit I figured out that if I take the [0] value of an identity modelViewProjection matrix and multiply it by 16 I get the depth required to get 1:1 pixels. I don't know why. I don't know if the 16 is related to the screen size or just a lucky guess. But I did a test where I placed a sprite at that calculated depth and varied the FOV through all the valid values and the object stays steady on screen with 1:1 pixels. So now I'm just calculating the unityDepth that way. If someone gives me a better answer I'll checkmark it.

  Read the article

• Scene transitions

  - by Mars

  It's my first time working with actual scenes/states, aka DrawableGameComponents, which work separate from one another. I'm now wondering what's the best way to make transitions between them, and how to affect them from other scenes. Lets say I wanted to "push" one screen to the right, with another one coming in at the same time. Naturally I'd have to keep drawing both, until the transition is complete. And I'd have to adjust the coordinates I'm drawing at while doing it. Is there a way around specifically handling this special case in every single scene? Or of I wanted to fade one into the other. Basically the question stays the same, how would you do that without having to handle it in every single scene? While writing this I'm realizing it will be the same thing for all kinds of transitions. Maybe a central Draw method in the manager could be a solution, where parameters and effects are applied when necessary. But this wouldn't work if objects that are drawn have their own method, and aren't drawn within the scene, or if an effect has to be applied to the whole scene. That means, maybe scenes have to be drawn to their own rendertarget? That way one call to the base class after the normal drawing could be enough, to apply the effects, while drawing it to the main render target. But I once heard there are problems when switching from target to target, back and forth. So is that even a viable option? As you can see, I have some basic ideas how it might work... but nothing specific. I'd like to learn what's the common way to achieve such things, a general way to apply all kinds of transitions.

  Read the article

< Previous Page | 517 518 519 520 521 522 523 524 525 526 527 528  | Next Page >