Search Results

Search found 32114 results on 1285 pages for 'general development'.

Page 491/1285 | < Previous Page | 487 488 489 490 491 492 493 494 495 496 497 498  | Next Page >

• How to categorize textures into atlases

  - by Esa

  I am going to use texture atlasing for the first time in my games, and at first it seemed like a great idea to split textures into atlases by categorizing them by terrain themes e.g ForestTextures, WinterTextures etc. But that could cause a problem when for example a flower has to use transparency shader and other models use a diffuse shader. So those cannot be atlased into the same texture. Thus, would atlasing textures into themes as mentioned before and then splitting them by shader like ForestDiffuse and ForestTransparent be good? Or is there a better way to categorize and build them?

  Read the article

• Finding closest object to a location within a specific perpendicular distance to direction vector

  - by Sniper

  I have a location and a direction vector indicating facing, I want to find the closest object to that location that is within some tolerance distance (perpendicular distance) to the ray formed by the location and direction vector. Basically I want to get the object that is being aimed at. I have thought about finding all objects within a box and then finding the closest object to my vector from them results, but I am sure that there is a more efficient way. The Z axis is optional, the objects are most likely within a few meters of the search vector.

  Read the article

• Orthographic Projection with variable FOV

  - by cubrman

  We are building agame with orthographic view. The problem we face is the fact that with different resolution you can see different area of the game world. E.g. if you have higher resolution you can see more around you. To solve this we currently use a common scale factor that every model is scaled by, depending on resolution. But this has drawbacks when drawing shadows - I cannot set a higher view angle for the orthographic shadow camera, while when using the perspective shadow camera I get significantly worse shadow quality. So the question is is there any way to controll FOV when using orthographic projection, or, more specifically, what is the easiest way to scale the world uniformly up or down with orthographic projection matrix? I saw that in 3ds MAX you can control FOV for an orthographic camera I wonder how they implemented it.

  Read the article

• Object-Oriented OpenGL

  - by Sullivan

  I have been using OpenGL for a while and have read a large number of tutorials. Aside from the fact that a lot of them still use the fixed pipeline, they usually throw all the initialisation, state changes and drawing in one source file. This is fine for the limited scope of a tutorial, but I’m having a hard time working out how to scale it up to a full game. How do you split your usage of OpenGL across files? Conceptually, I can see the benefits of having, say, a rendering class that purely renders stuff to screen, but how would stuff like shaders and lights work? Should I have separate classes for things like lights and shaders?

  Read the article

• Basic procedural generated content works, but how could I do the same in reverse?

  - by andrew

  My 2D world is made up of blocks. At the moment, I create a block and assign it a number between 1 and 4. The number assigned to the nth block is always the same (i.e if the player walks backwards or restarts the game.) and is generated in the function below. As shown here by this animation, the colours represent the number. function generate_data(n) math.randomseed(n) -- resets the random so that the 'random' number for n is always the same math.random() -- fixes lua random bug local no = math.random(4) --print(no, n) return no end Now I want to limit the next block's number - a block of 1 will always have a block 2 after it, while block 2 will either have a block 1,2 or 3 after it, etc. Before, all the blocks data was randomly generated, initially, and then saved. This data was then loaded and used instead of being randomly called. While working this way, I could specify what the next block would be easily and it would be saved for consistency. I have now removed this saving/loading in favour of procedural generation as I realised that save whiles would get very big after travelling. Back to the present. While travelling forward (to the right), it is easy to limit what the next blocks number will be. I can generate it at the same time as the other data. The problem is when travelling backwards (to the left) I can not think of a way to load the previous block so that it is always the same. Does anyone have any ideas on how I could sort this out?

  Read the article

• how do I set quad buffering with jogl 2.0

  - by tony danza

  I'm trying to create a 3d renderer for stereo vision with quad buffering with Processing/Java. The hardware I'm using is ready for this so that's not the problem. I had a stereo.jar library in jogl 1.0 working for Processing 1.5, but now I have to use Processing 2.0 and jogl 2.0 therefore I have to adapt the library. Some things are changed in the source code of Jogl and Processing and I'm having a hard time trying to figure out how to tell Processing I want to use quad buffering. Here's the previous code: public class Theatre extends PGraphicsOpenGL{ protected void allocate() { if (context == null) { // If OpenGL 2X or 4X smoothing is enabled, setup caps object for them GLCapabilities capabilities = new GLCapabilities(); // Starting in release 0158, OpenGL smoothing is always enabled if (!hints[DISABLE_OPENGL_2X_SMOOTH]) { capabilities.setSampleBuffers(true); capabilities.setNumSamples(2); } else if (hints[ENABLE_OPENGL_4X_SMOOTH]) { capabilities.setSampleBuffers(true); capabilities.setNumSamples(4); } capabilities.setStereo(true); // get a rendering surface and a context for this canvas GLDrawableFactory factory = GLDrawableFactory.getFactory(); drawable = factory.getGLDrawable(parent, capabilities, null); context = drawable.createContext(null); // need to get proper opengl context since will be needed below gl = context.getGL(); // Flag defaults to be reset on the next trip into beginDraw(). settingsInited = false; } else { // The following three lines are a fix for Bug #1176 // http://dev.processing.org/bugs/show_bug.cgi?id=1176 context.destroy(); context = drawable.createContext(null); gl = context.getGL(); reapplySettings(); } } } This was the renderer of the old library. In order to use it, I needed to do size(100, 100, "stereo.Theatre"). Now I'm trying to do the stereo directly in my Processing sketch. Here's what I'm trying: PGraphicsOpenGL pg = ((PGraphicsOpenGL)g); pgl = pg.beginPGL(); gl = pgl.gl; glu = pg.pgl.glu; gl2 = pgl.gl.getGL2(); GLProfile profile = GLProfile.get(GLProfile.GL2); GLCapabilities capabilities = new GLCapabilities(profile); capabilities.setSampleBuffers(true); capabilities.setNumSamples(4); capabilities.setStereo(true); GLDrawableFactory factory = GLDrawableFactory.getFactory(profile); If I go on, I should do something like this: drawable = factory.getGLDrawable(parent, capabilities, null); but drawable isn't a field anymore and I can't find a way to do it. How do I set quad buffering? If I try this: gl2.glDrawBuffer(GL.GL_BACK_RIGHT); it obviously doesn't work :/ Thanks.

  Read the article

• Numerically stable(ish) method of getting Y-intercept of mouse position?

  - by Fraser

  I'm trying to unproject the mouse position to get the position on the X-Z plane of a ray cast from the mouse. The camera is fully controllable by the user. Right now, the algorithm I'm using is... Unproject the mouse into the camera to get the ray: Vector3 p1 = Vector3.Unproject(new Vector3(x, y, 0), 0, 0, width, height, nearPlane, farPlane, viewProj; Vector3 p2 = Vector3.Unproject(new Vector3(x, y, 1), 0, 0, width, height, nearPlane, farPlane, viewProj); Vector3 dir = p2 - p1; dir.Normalize(); Ray ray = Ray(p1, dir); Then get the Y-intercept by using algebra: float t = -ray.Position.Y / ray.Direction.Y; Vector3 p = ray.Position + t * ray.Direction; The problem is that the projected position is "jumpy". As I make small adjustments to the mouse position, the projected point moves in strange ways. For example, if I move the mouse one pixel up, it will sometimes move the projected position down, but when I move it a second pixel, the project position will jump back to the mouse's location. The projected location is always close to where it should be, but it does not smoothly follow a moving mouse. The problem intensifies as I zoom the camera out. I believe the problem is caused by numeric instability. I can make minor improvements to this by doing some computations at double precision, and possibly abusing the fact that floating point calculations are done at 80-bit precision on x86, however before I start micro-optimizing this and getting deep into how the CLR handles floating point, I was wondering if there's an algorithmic change I can do to improve this? EDIT: A little snooping around in .NET Reflector on SlimDX.dll: public static Vector3 Unproject(Vector3 vector, float x, float y, float width, float height, float minZ, float maxZ, Matrix worldViewProjection) { Vector3 coordinate = new Vector3(); Matrix result = new Matrix(); Matrix.Invert(ref worldViewProjection, out result); coordinate.X = (float) ((((vector.X - x) / ((double) width)) * 2.0) - 1.0); coordinate.Y = (float) -((((vector.Y - y) / ((double) height)) * 2.0) - 1.0); coordinate.Z = (vector.Z - minZ) / (maxZ - minZ); TransformCoordinate(ref coordinate, ref result, out coordinate); return coordinate; } // ... public static void TransformCoordinate(ref Vector3 coordinate, ref Matrix transformation, out Vector3 result) { Vector3 vector; Vector4 vector2 = new Vector4 { X = (((coordinate.Y * transformation.M21) + (coordinate.X * transformation.M11)) + (coordinate.Z * transformation.M31)) + transformation.M41, Y = (((coordinate.Y * transformation.M22) + (coordinate.X * transformation.M12)) + (coordinate.Z * transformation.M32)) + transformation.M42, Z = (((coordinate.Y * transformation.M23) + (coordinate.X * transformation.M13)) + (coordinate.Z * transformation.M33)) + transformation.M43 }; float num = (float) (1.0 / ((((transformation.M24 * coordinate.Y) + (transformation.M14 * coordinate.X)) + (coordinate.Z * transformation.M34)) + transformation.M44)); vector2.W = num; vector.X = vector2.X * num; vector.Y = vector2.Y * num; vector.Z = vector2.Z * num; result = vector; } ...which seems to be a pretty standard method of unprojecting a point from a projection matrix, however this serves to introduce another point of possible instability. Still, I'd like to stick with the SlimDX Unproject routine rather than writing my own unless it's really necessary.

  Read the article

• A good way to build a game loop in OpenGL

  - by Jeff

  I'm currently beginning to learn OpenGL at school, and I've started making a simple game the other day (on my own, not for school). I'm using freeglut, and am building it in C, so for my game loop I had really just been using a function I made passed to glutIdleFunc to update all the drawing and physics in one pass. This was fine for simple animations that I didn't care too much about the frame rate, but since the game is mostly physics based, I really want to (need to) tie down how fast it's updating. So my first attempt was to have my function I pass to glutIdleFunc (myIdle()) to keep track of how much time has passed since the previous call to it, and update the physics (and currently graphics) every so many milliseconds. I used timeGetTime() to do this (by using <windows.h>). And this got me to thinking, is using the idle function really a good way of going about the game loop? My question is, what is a better way to implement the game loop in OpenGL? Should I avoid using the idle function?

  Read the article

• Multiple Vertex Buffers per Mesh

  - by Daniel

  I've run into the situation where the size of my mesh with all its vertices and indices, is larger than the (optimal) vertex buffer object upper limit (~8MB). I was wondering if I can sub-divide the mesh across multiple vertex buffers, and somehow retain validity of the indices. Ie a triangle with a indice at the first vertex, and an indice at the last (ie in seperate VBOs). All the while maintaining this within Vertex Array Objects. My thoughts are, save myself the hassle, and for meshes (messes :P) such as this, just use the necessary size ( 8MB); which is what I do at the moment. But ideally my buffer manager (wip) at the moment is using optimal sizes; I may just have to make a special case then... Any ideas? If necessary, a simple C++ code example is appreciated. Note: I have also cross-posted this on stackoverflow, as I was not sure as to which it would be more suitable (its partly a design question).

  Read the article

• Camera movement and threshold not working

  - by irish guy mcconagheh

  I have a platformer that is in progress, part of this has a camera which I only want to move when the character moves out of a certain threshold, to try to accomplish this I have the following if statement: if(((Mathf.Abs(target.transform.position.x))-(Mathf.Abs(transform.position.x)))>thres){ x = moveTo(transform.position.x, target.position.x, trackSpeed); } in unity/c#. In pseudocode it means if((absolute value of player x) - (absolute value of camera x) is greater than the threshold){ move { however this does not seem to work correctly. it appears to work for the first couple of times the threshold is reached, however the distance between the camera and the player has to increase every time for the camera to move. I do not believe the movement of the camera is the problem, however the code for it is as follows: private float moveTo(float n, float target, float accel) { if (n == target) { return n; } else { float dir = Mathf.Sign(target - n); n += accel * Time.deltaTime * dir; return (dir == Mathf.Sign(target-n))? n: target; } } }

  Read the article

• How do you pack resources in a game when you have too many of them?

  - by ThePlan

  I've recently made a basic space invaders clone in C++ using the Allegro 5 framework. It took me a long time, but after I finished, I realized I had about 10 sprites, and 13MB worth of DLLs (Some of the people didn't even have the mingW dlls) which were making people who played the game very confused. How can I "pack" all my resources in a way that I can easily add-remove data to my game, and to reduce the size taken by the resource, basically placing them in 1 spot? I'm using codeblocks.

  Read the article

• Slick 2d scrolling off screen

  - by Peter

  I have something scrolling in and out of the screen. Now when it goes off screen, I want it to scroll into the screen at another location. What I do is I grab the last pixels at the screens edge using g.copyArea and then g.drawImage on the edge of the screen. And then I do a g.translate to create room for the next row which is next render cycle. My problem is that I get a single pixel row, which is not copied onto the canvas. Where as I want each row to be added and then translated, so that the image that scrolled off screen is recreated on the other side of the screen. Here is my code, maybe there is a better way of doing this, open to any suggests, cause I'm totally stuck @Override public void render(GameContainer gc, Graphics g) throws SlickException { //g.setClip(0, 0, 300, gc.getHeight()); g.translate(0, y); g.drawImage(image,0,200); g.resetTransform(); //g.clearClip(); g.copyArea(rightImage, 0, gc.getHeight() - 1); g.drawImage(rightImage, 300, 0); g.translate(0, y); y=y+3; }

  Read the article

• How to make my simple round sprite look right in XNA

  - by Joshua Perina

  Ok, I'm very new to graphics programming (but not new to coding). I'm trying to load a simple image in XNA which I can do fine. It is a simple round circle which I made in photoshop. The problem is the edges show up rough when I draw it on the screen even with the exact size. The anti-aliasing is missing. I'm sure I'm missing something very simple: GraphicsDevice.Clear(Color.Black); // TODO: Add your drawing code here spriteBatch.Begin(); spriteBatch.Draw(circle, new Rectangle(10, 10, 10, 10), Color.White); spriteBatch.End(); Couldn't post picture because I'm a first time poster. But my smooth png circle has rough edges. So I found that if I added: spriteBatch.Begin(SpriteSortMode.FrontToBack, BlendState.NonPremultiplied); I can get a smooth image when the image is the same size as the original png. But if I want to scale that image up or down then the rough edges return. How do I get XNA to smoothly resize my simple round image to a smaller size without getting the rough edges?

  Read the article

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

  - by Bradley Uffner

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

  Read the article

• How to snap a 2D Quad to the mouse cursor using OpenGL 3.0/WIN32?

  - by NoobScratcher

  I've been having issues trying to snap a 2D Quad to the mouse cursor position I'm able : 1.) To get values into posX, posY, posZ 2.) Translate with the values from those 3 variables But the quad positioning I'm not able to do correctly in such a way that the 2D Quad is near the mouse cursor using those values from those 3 variables eg."posX, posY, posZ" I need the mouse cursor in the center of the 2D Quad. I'm hoping someone can help me achieve this. I've tried searching around with no avail. Heres the function that is ment to do the snapping but instead creates weird flicker or shows nothing at all only the 3d models show up : void display() { glClearColor(0.0,0.0,0.0,1.0); glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT); for(std::vector<GLuint>::iterator I = cube.begin(); I != cube.end(); ++I) { glCallList(*I); } if(DrawArea == true) { glReadPixels(winX, winY, 1, 1, GL_DEPTH_COMPONENT, GL_FLOAT, &winZ); cerr << winZ << endl; glGetDoublev(GL_MODELVIEW_MATRIX, modelview); glGetDoublev(GL_PROJECTION_MATRIX, projection); glGetIntegerv(GL_VIEWPORT, viewport); gluUnProject(winX, winY, winZ , modelview, projection, viewport, &posX, &posY, & posZ); glBindTexture(GL_TEXTURE_2D, DrawAreaTexture); glPixelStorei(GL_UNPACK_ALIGNMENT, 1); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL); glTexImage2D (GL_TEXTURE_2D, 0, GL_RGB, DrawAreaSurface->w, DrawAreaSurface->h, 0, GL_RGBA, GL_UNSIGNED_BYTE, DrawAreaSurface->pixels); glEnable(GL_TEXTURE_2D); glBindTexture(GL_TEXTURE_2D, DrawAreaTexture); glTranslatef(posX , posY, posZ); glBegin(GL_QUADS); glTexCoord2f (0.0, 0.0); glVertex3f(0.5, 0.5, 0); glTexCoord2f (1.0, 0.0); glVertex3f(0, 0.5, 0); glTexCoord2f (1.0, 1.0); glVertex3f(0, 0, 0); glTexCoord2f (0.0, 1.0); glVertex3f(0.5, 0, 0); glEnd(); } SwapBuffers(hDC); } I'm using : OpenGL 3.0 WIN32 API C++ GLSL if you really want the full source here it is - http://pastebin.com/1Ncm9HNf , Its pretty messy.

  Read the article

• How to perform efficient 2D picking in HTML5?

  - by jSepia

  I'm currently using an R-Tree for both picking and collision testing. Each entity on screen has a bounding box for collisions and a separate one for picking. Since entities may change position very frequently, both trees must be updated/reordered once per frame. While this is very efficient for collisions, because the tree is used in hundreds of collision queries every frame, I'm finding it too costly for picking, because it only gets queried when the user clicks, thus leading to a lot of wasted tree updates. What would be a more efficient way to implement picking without as much overhead?

  Read the article

• Variables in static library are never initialized. Why?

  - by Coyote

  I have a bunch of variables that should be initialized then my game launches, but must of them are never initialized. Here is an example of the code: MyClass.h class MyClass : public BaseObject { DECLARE_CLASS_RTTI(MyClass, BaseObject); ... }; MyClass.cpp REGISTER_CLASS(MyClass) Where REGISTER_CLASS is a macro defined as follow #define REGISTER_CLASS(className)\ class __registryItem##className : public __registryItemBase {\ virtual className* Alloc(){ return NEW className(); }\ virtual BaseObject::RTTI& GetRTTI(){ return className::RTTI; }\ }\ \ const __registryItem##className __registeredItem##className(#className); and __registryItemBase looks like this: class __registryItemBase { __registryItemBase(const _string name):mName(name){ ClassRegistry::Register(this); } const _string mName; virtual BaseObject* Alloc() = 0; virtual BaseObject::RTTI& GetRTTI() = 0; } Now the code is similar to what I currently have and what I have works flawlessly, all the registered classes are registered to a ClassManager before main(...) is called. I'm able to instantiate and configure components from scripts and auto-register them to the right system etc... The problem arrises when I create a static library (currently for the iPhone, but I fear it will happen with android as well). In that case the code in the .cpp files is never registered. Why is the resulting code not executed when it is in the library while the same code in the program's binary is always executed? Bonus questions: For this to work in the static library, what should I do? Is there something I am missing? Do I need to pass a flag when building the lib? Should I create another structure and init all the __registeredItem##className using that structure?

  Read the article

• Ogre3D : seeking advices about game files management

  - by Tibor

  I'm working on a new game, and its related level editor, based on Ogre3D. I was thinking about how i could manage the game files, knowing that Ogre use .mesh files for models, .material for materials/texture information etc... . At first i thought about a common .zip folder decompressed at runtime (the same way Torchlight and Ogre samples do). But this way the game assets become a monolithic archive, loading takes time, and could be difficult to eventually patch them. So, let's say i have a game object named "Cube" i want to load in my program. Going for modularity, what if i create a compressed file (using zlib compression routines) named Cube.extname, containing its sub-files Cube.mesh, Cube.material and so on ? Are there any alternatives or should i stick with compressed objects? PS: Just to clear things, the answer is unrelated to my program code, at the moment i'm using "resources.cfg" pointing to the OgreSDK media directory.

  Read the article

• Order independent transparency in particle system

  - by Stepan Zastupov

  I'm writing a particle system and would like to find a trick to achieve proper alpha blending without sorting particles because: Each particle is a point sprite in a single mesh and I can't use scene graph ability to sort transparent nodes. The system node should be properly sorted, though. Particle position is computed on shader from initial velocity, acceleration and time. In order to sort the system I would have to perform all this computations on CPU, which is something I want to avoid. Sorting hundreds of particles against camera position and uploading it on GPU each frame seams to be quiet heavy operation. Alpha testing seems to be fast enough on GLES 2.0 and works fine for non-transparent but "masked" textures. Still, it's not enough for semi-transparent particles. How would you handle this?

  Read the article

• 2D wave-like sprite movement XNA

  - by TheBroodian

  I'm trying to create a particle that will 'circle' my character. When the particle is created, it's given a random position in relation to my character, and a box to provide boundaries for how far left or right this particle should circle. When I use the phrase 'circle', I'm referring to a simulated circling, i.e., when moving to the right, the particle will appear in front of my character, when passing back to the left, the particle will appear behind my character. That may have been too much context, so let me cut to the chase: In essence, the path I would like my particle to follow would be akin to a sine wave, with the left and right sides of the provided rectangle being the apexes of the wave. The trouble I'm having is that the position of the particle will be random, so it will never be produced at the same place within the wave twice, but I have no idea how to create this sort of behavior procedurally.

  Read the article

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

  - by Triynko

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

  Read the article

• Actor and Sprite, who should own these properties?

  - by Gerardo Marset

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

  Read the article

• Would someone please explain Octree Collisions to me?

  - by A-Type

  I've been reading everything I can find on the subject and I feel like the pieces are just about to fall into place, but I just can't quite get it. I'm making a space game, where collisions will occur between planets, ships, asteroids, and the sun. Each of these objects can be subdivided into 'chunks', which I have implemented to speed up rendering (the vertices can and will change often at runtime, so I've separated the buffers). These subdivisions also have bounding primitives to test for collision. All of these objects are made of blocks (yeah, it's that kind of game). Blocks can also be tested for rough collisions, though they do not have individual bounding primitives for memory reasons. I think the rough testing seems to be sufficient, though. So, collision needs to be fairly precise; at block resolution. Some functions rely on two blocks colliding. And, of course, attacking specific blocks is important. Now what I am struggling with is filtering my collision pairs. As I said, I've read a lot about Octrees, but I'm having trouble applying it to my situation as many tutorials are vague with very little code. My main issues are: Are Octrees recalculated each frame, or are they stored in memory and objects are shuffled into different divisions as they move? Despite all my reading I still am not clear on this... the vagueness of it all has been frustrating. How far do Octrees subdivide? Planets in my game are quite large, while asteroids are smaller. Do I subdivide to the size of the planet, or asteroid (where planet is in multiple divisions)? Or is the limit something else entirely, like number of elements in the division? Should I load objects into the octrees as 'chunks' or in the whole, then break into chunks later? This could be specific to my implementation, I suppose. I was going to ask about how big my root needed to be, but I did manage to find this question, and the second answer seems sufficient for me. I'm afraid I don't really get what he means by adding new nodes and doing subdivisions upon adding new objects, probably because I'm confused about whether the tree is maintained in memory or recalculated per-frame.

  Read the article

• Rotating wheel with touch adding velocity

  - by Lewis

  I have a wheel control in a game which is setup like so: - (void)ccTouchesMoved:(NSSet *)touches withEvent:(UIEvent *)event { UITouch *touch = [touches anyObject]; CGPoint location = [touch locationInView:[touch view]]; location = [[CCDirector sharedDirector] convertToGL:location]; if (CGRectContainsPoint(wheel.boundingBox, location)) { CGPoint firstLocation = [touch previousLocationInView:[touch view]]; CGPoint location = [touch locationInView:[touch view]]; CGPoint touchingPoint = [[CCDirector sharedDirector] convertToGL:location]; CGPoint firstTouchingPoint = [[CCDirector sharedDirector] convertToGL:firstLocation]; CGPoint firstVector = ccpSub(firstTouchingPoint, wheel.position); CGFloat firstRotateAngle = -ccpToAngle(firstVector); CGFloat previousTouch = CC_RADIANS_TO_DEGREES(firstRotateAngle); CGPoint vector = ccpSub(touchingPoint, wheel.position); CGFloat rotateAngle = -ccpToAngle(vector); CGFloat currentTouch = CC_RADIANS_TO_DEGREES(rotateAngle); wheelRotation += (currentTouch - previousTouch) * 0.6; //limit speed 0.6 } } I update the rotation of a the wheel in the update method by doing: wheel.rotation = wheelRotation; Now once the user lets go of the wheel I want it to rotate back to where it was before but not without taking into account the velocity of the swipe the user has done. This is the bit I really can't get my head around. So if the swipe generates a lot of velocity then the wheel will carry on moving slightly in that direction until the overall force which pulls the wheel back to the starting position kicks in. Any ideas/code snippets?

  Read the article

• Resources on expected behaviour when manipulating 3D objects with the mouse

  - by sebf

  Hello, In my animation editor, I have a 3D gizmo that sits on the origin of a bone; the user drags the mesh around to rotate the bone. I've found that translating the 2D movements of the mouse into sensible 3D transforms is not near as simple as i'd hoped. For example what is intuitively 'up' or 'down'? How should the magnitude of rotations change with respect to dX/dY? How to implement this? What happens when the gizmo changes position or orientation with respect to the camera? ect. So far with trial and error i've written something (very) simple that works 70% of the time. I could probably continue to hack at it until I made something that works 99% of the time, but there must be someone who needed the same thing, and spent the time coming up with a much more elegant solution. Does anyone know of one?

  Read the article

< Previous Page | 487 488 489 490 491 492 493 494 495 496 497 498  | Next Page >