Search Results

Search found 28914 results on 1157 pages for 'cloud development'.

Page 520/1157 | < Previous Page | 516 517 518 519 520 521 522 523 524 525 526 527  | Next Page >

  • Why am I getting a return value of zero from my position computation function?

    - by Hussain Murtaza
    Ok I have a Function int x(), which is used in new Rectangle(x(),a,a,a); in DrawMethod in XNA but when I use it I get x() = 0 as as the answer.Here is my CODE: int x() { int px = (128 * 5); int xx = 0; for (int i = 0; i < 6; i++) { if (Mouse.GetState().X > px) { //xx = Mouse.GetState().X; xx = px; break; } else { px -= 128; } } return xx; } Here is the DrawMethod Code: if (set) { spriteBatch.Draw(texture, new Rectangle(x(), y(), texture.Width, texture.Height), Color.White); textpositionX = x(); textpositionY = y(); set = false; select = false; place = true; } else if(select) { spriteBatch.Draw(texture, new Rectangle(Mouse.GetState().X - texture.Width / 2, Mouse.GetState().Y-texture.Height / 2, texture.Width, texture.Height), Color.White); } else if (place) { spriteBatch.Draw(texture, new Rectangle(textpositionX, textpositionY, texture.Width, texture.Height), Color.White); select = false; set = false; }

    Read the article

  • How should I interpret these DirectX Caps Viewer values?

    - by tobi
    Briefly asking - what do the nodes mean and what the difference is between them in DirectX Caps Viewer? DXGI Devices Direct3D9 Devices DirectDraw Devices The most interesting for me is 1 vs 2. In the Direct3D9 Devices under HAL node I can see that my GeForce 8800GT supports PixelShaderVersion 3.0. However, under DXGI Devices I have DX 10, DX 10.1 and DX 11 having Shader model 4.0 (actually why DX 11? My card is not compatible with DX 11). I am implementing a DX 11 application (including d3d11.h) with shaders compiled in 4.0 version, so I can clearly see that 4.0 is supported. What is the difference between 1 and 2? Could you give me some theory behind the nodes?

    Read the article

  • Floodfill algorithm for GO

    - by user1048606
    The floodfill algorithm is used in the bucket tool in MS paint and photoshop, but it can also be used for GO and minesweeper. http://en.wikipedia.org/wiki/Flood_fill In go you can capture groups of stones, this website portrays it with two stones. http://www.connectedglobe.com/mindy/cap6.html This is my floodfill method in Java, it is not capturing a group of stones and I have no idea why because to me it makes sense. public void floodfill(int turn, int col, int row){ for(int a = col; a<19; a++){ for(int b = row; b<19; b++){ if(turn == black){ if(stones[col][row] == white){ stones[col][row] = 0; floodfill(black, col-1, row); floodfill(black, col+1, row); floodfill(black, col, row-1); floodfill(black, col, row+1); } } } } } It searches up, down, left, right for all the stones on the board. If the stones are white it captures them by making them 0, which represents empty.

    Read the article

  • Stop a rotating object at a specified angle?

    - by Krummelz
    I'm working in JavaScript with HTML5 and the canvas. I have an object which is rotating at a certain speed, and I need the object's rotation to slow down gradually and the front of the object to stop at a specified angle. (I'm using radians, not degrees.) I have a variable to keep track of the angle which the object is facing, as it rotates. How would I go about getting the object to come to rest, facing the direction I want it to?

    Read the article

  • Issues with shooting in a HTML5 platformer game

    - by fnx
    I'm coding a 2D sidescroller using only JavaScript and HTML5 canvas, and in my game I have two problems with shooting: 1) Player shoots continous stream of bullets. I want that player can shoot only a single bullet even though the shoot-button is being held down. 2) Also, I get an error "Uncaught TypeError: Cannot call method 'draw' of undefined" when all the bullets are removed. My shooting code goes like this: When player shoots, I do game.bullets.push(new Bullet(this, this.scale)); and after that: function Bullet(source, dir) { this.id = "bullet"; this.width = 10; this.height = 3; this.dir = dir; if (this.dir == 1) { this.x = source.x + source.width - 5; this.y = source.y + 16; } if (this.dir == -1) { this.x = source.x; this.y = source.y + 16; } } Bullet.prototype.update = function() { if (this.dir == 1) this.x += 8; if (this.dir == -1) this.x -= 8; for (var i in game.enemies) { checkCollisions(this, game.enemies[i]); } // Check if bullet leaves the viewport if (this.x < game.viewX * 32 || this.x > (game.viewX + game.tilesX) * 32) { removeFromList(game.bullets, this); } } Bullet.prototype.draw = function() { // bullet flipping uses orientation of the player var posX = game.player.scale == 1 ? this.x : (this.x + this.width) * -1; game.ctx.scale(game.player.scale, 1); game.ctx.drawImage(gameData.getGfx("bullet"), posX, this.y); } I handle removing with this function: function removeFromList(list, object) { for (i in list) { if (object == list[i]) { list.splice(i, 1); break; } } } And finally, in the main game loop I have this: for (var i in game.bullets) { game.bullets[i].update(); game.bullets[i].draw(); } I have tried adding if (game.bullets.length > 0) to the main game loop before the above draw&update calls, but I still get the same error.

    Read the article

  • Physics not synchronizing correctly over the network when using Bullet

    - by Lucas
    I'm trying to implement a client/server physics system using Bullet however I'm having problems getting things to sync up. I've implemented a custom motion state which reads and write the transform from my game objects and it works locally but I've tried two different approaches for networked games: Dynamic objects on the client that are also on the server (eg not random debris and other unimportant stuff) are made kinematic. This works correctly but the objects don't move very smoothly Objects are dynamic on both but after each message from the server that the object has moved I set the linear and angular velocity to the values from the server and call btRigidBody::proceedToTransform with the transform on the server. I also call btCollisionObject::activate(true); to force the object to update. My intent with method 2 was to basically do method 1 but hijacking Bullet to do a poor-man's prediction instead of doing my own to smooth out method 1, but this doesn't seem to work (for reasons that are not 100% clear to me even stepping through Bullet) and the objects sometimes end up in different places. Am I heading in the right direction? Bullet seems to have it's own interpolation code built-in. Can that help me make method 1 work better? Or is my method 2 code not working because I am accidentally stomping that?

    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

  • Break the object body

    - by Siddharth
    In my game, I want to break the object body creating slicing effect. After research I found that I have to use ray casting but I don't know how to use it. If some one know how to break the physics body then please provide information to me. EDIT : I don't have any logic how to do that in andengine. Only I have some link to do slicing http://www.emanueleferonato.com/2012/03/05/breaking-objects-with-box2d-the-realistic-way/ Yes I have to slice physics body into two parts. My physics body have 2d objects.

    Read the article

  • Complete Guide/Tutorials on LWJGL?

    - by user43353
    Dont get me wrong, I finished these tutorials on http://lwjgl.org/wiki/index.php?title=Main_Page. I finished The Basics section, OpenGL 3.2 and newer section, and I looked at the Example Code section. They were great tutorials, and I have looked at the external tutorials as well. I don't know where to go from here, and OpenGL is not my strong point. Some one suggested Learning Modern 3D Graphics Programming, and I didnt learn much. I looked at the port to LWJGL, but the book was on C and I couldn't really understand what the OpenGL meant. I am trying to learn 2D gaming, not 3D. Maybe later. Is there any tutorials that aren't C/C++ heavy and teach you 2D OpenGL?

    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

  • Relative cam movement and momentum on arbitrary surface

    - by user29244
    I have been working on a game for quite long, think sonic classic physics in 3D or tony hawk psx, with unity3D. However I'm stuck at the most fundamental aspect of movement. The requirement is that I need to move the character in mario 64 fashion (or sonic adventure) aka relative cam input: the camera's forward direction always point input forward the screen, left or right input point toward left or right of the screen. when input are resting, the camera direction is independent from the character direction and the camera can orbit the character when input are pressed the character rotate itself until his direction align with the direction the input is pointing at. It's super easy to do as long your movement are parallel to the global horizontal (or any world axis). However when you try to do this on arbitrary surface (think moving along complex curved surface) with the character sticking to the surface normal (basically moving on wall and ceiling freely), it seems harder. What I want is to achieve the same finesse of movement than in mario but on arbitrary angled surfaces. There is more problem (jumping and transitioning back to the real world alignment and then back on a surface while keeping momentum) but so far I didn't even take off the basics. So far I have accomplish moving along the curved surface and the relative cam input, but for some reason direction fail all the time (point number 3, the character align slowly to the input direction). Do you have an idea how to achieve that? Here is the code and some demo so far: The demo: https://dl.dropbox.com/u/24530447/flash%20build/litesonicengine/LiteSonicEngine5.html Camera code: using UnityEngine; using System.Collections; public class CameraDrive : MonoBehaviour { public GameObject targetObject; public Transform camPivot, camTarget, camRoot, relcamdirDebug; float rot = 0; //---------------------------------------------------------------------------------------------------------- void Start() { this.transform.position = targetObject.transform.position; this.transform.rotation = targetObject.transform.rotation; } void FixedUpdate() { //the pivot system camRoot.position = targetObject.transform.position; //input on pivot orientation rot = 0; float mouse_x = Input.GetAxisRaw( "camera_analog_X" ); // rot = rot + ( 0.1f * Time.deltaTime * mouse_x ); // wrapAngle( rot ); // //when the target object rotate, it rotate too, this should not happen UpdateOrientation(this.transform.forward,targetObject.transform.up); camRoot.transform.RotateAround(camRoot.transform.up,rot); //debug the relcam dir RelativeCamDirection() ; //this camera this.transform.position = camPivot.position; //set the camera to the pivot this.transform.LookAt( camTarget.position ); // } //---------------------------------------------------------------------------------------------------------- public float wrapAngle ( float Degree ) { while (Degree < 0.0f) { Degree = Degree + 360.0f; } while (Degree >= 360.0f) { Degree = Degree - 360.0f; } return Degree; } private void UpdateOrientation( Vector3 forward_vector, Vector3 ground_normal ) { Vector3 projected_forward_to_normal_surface = forward_vector - ( Vector3.Dot( forward_vector, ground_normal ) ) * ground_normal; camRoot.transform.rotation = Quaternion.LookRotation( projected_forward_to_normal_surface, ground_normal ); } float GetOffsetAngle( float targetAngle, float DestAngle ) { return ((targetAngle - DestAngle + 180)% 360) - 180; } //---------------------------------------------------------------------------------------------------------- void OnDrawGizmos() { Gizmos.DrawCube( camPivot.transform.position, new Vector3(1,1,1) ); Gizmos.DrawCube( camTarget.transform.position, new Vector3(1,5,1) ); Gizmos.DrawCube( camRoot.transform.position, new Vector3(1,1,1) ); } void OnGUI() { GUI.Label(new Rect(0,80,1000,20*10), "targetObject.transform.up : " + targetObject.transform.up.ToString()); GUI.Label(new Rect(0,100,1000,20*10), "target euler : " + targetObject.transform.eulerAngles.y.ToString()); GUI.Label(new Rect(0,100,1000,20*10), "rot : " + rot.ToString()); } //---------------------------------------------------------------------------------------------------------- void RelativeCamDirection() { float input_vertical_movement = Input.GetAxisRaw( "Vertical" ), input_horizontal_movement = Input.GetAxisRaw( "Horizontal" ); Vector3 relative_forward = Vector3.forward, relative_right = Vector3.right, relative_direction = ( relative_forward * input_vertical_movement ) + ( relative_right * input_horizontal_movement ) ; MovementController MC = targetObject.GetComponent<MovementController>(); MC.motion = relative_direction.normalized * MC.acceleration * Time.fixedDeltaTime; MC.motion = this.transform.TransformDirection( MC.motion ); //MC.transform.Rotate(Vector3.up, input_horizontal_movement * 10f * Time.fixedDeltaTime); } } Mouvement code: using UnityEngine; using System.Collections; public class MovementController : MonoBehaviour { public float deadZoneValue = 0.1f, angle, acceleration = 50.0f; public Vector3 motion ; //-------------------------------------------------------------------------------------------- void OnGUI() { GUILayout.Label( "transform.rotation : " + transform.rotation ); GUILayout.Label( "transform.position : " + transform.position ); GUILayout.Label( "angle : " + angle ); } void FixedUpdate () { Ray ground_check_ray = new Ray( gameObject.transform.position, -gameObject.transform.up ); RaycastHit raycast_result; Rigidbody rigid_body = gameObject.rigidbody; if ( Physics.Raycast( ground_check_ray, out raycast_result ) ) { Vector3 next_position; //UpdateOrientation( gameObject.transform.forward, raycast_result.normal ); UpdateOrientation( gameObject.transform.forward, raycast_result.normal ); next_position = GetNextPosition( raycast_result.point ); rigid_body.MovePosition( next_position ); } } //-------------------------------------------------------------------------------------------- private void UpdateOrientation( Vector3 forward_vector, Vector3 ground_normal ) { Vector3 projected_forward_to_normal_surface = forward_vector - ( Vector3.Dot( forward_vector, ground_normal ) ) * ground_normal; transform.rotation = Quaternion.LookRotation( projected_forward_to_normal_surface, ground_normal ); } private Vector3 GetNextPosition( Vector3 current_ground_position ) { Vector3 next_position; // //-------------------------------------------------------------------- // angle = 0; // Vector3 dir = this.transform.InverseTransformDirection(motion); // angle = Vector3.Angle(Vector3.forward, dir);// * 1f * Time.fixedDeltaTime; // // if(angle > 0) this.transform.Rotate(0,angle,0); // //-------------------------------------------------------------------- next_position = current_ground_position + gameObject.transform.up * 0.5f + motion ; return next_position; } } Some observation: I have the correct input, I have the correct translation in the camera direction ... but whenever I attempt to slowly lerp the direction of the character in direction of the input, all I get is wild spin! Sad Also discovered that strafing to the right (immediately at the beginning without moving forward) has major singularity trapping on the equator!! I'm totally lost and crush (I have already done a much more featured version which fail at the same aspect)

    Read the article

  • Basics of drawing in 2d with OpenGL 3 shaders

    - by davidism
    I am new to OpenGL 3 and graphics programming, and want to create some basic 2d graphics. I have the following scenario of how I might go about drawing a basic (but general) 2d rectangle. I'm not sure if this is the correct way to think about it, or, if it is, how to implement it. In my head, here's how I imagine doing it: t = make_rectangle(width, height) build general VBO, centered at 0, 0 optionally: t.set_scale(2) optionally: t.set_angle(30) t.draw_at(x, y) calculates some sort of scale/rotate/translate matrix (or matrices), passes the VBO and the matrix to a shader program Something happens to clip the world to the view visible on screen. I'm really unclear on how 4 and 5 will work. The main problem is that all the tutorials I find either: use fixed function pipeline, are for 3d, or are unclear how to do something this "simple". Can someone provide me with either a better way to think of / do this, or some concrete code detailing performing the transformations in a shader and constructing and passing the data required for this shader transformation?

    Read the article

  • Any significant performance cost to using BlendState.Premultiplied?

    - by Donutz
    Normally I guess you'd use BlendState.AlphaBlend because normally when you load your textures through the pipeline they're already premultiplied. However, if you're loading textures at runtime from PNGs or some such, you have to loop through the pixels and premultiply them, which can take a long time if you've got a lot of textures to load. So it looks (haven't tried it) like using BlendState.Premultiplied instead of BlendState.AlphaBlend should handle non-premultiplied textures and produce the same visual result, without all the startup costs. I have to wonder if there's a non-obvious cost to doing this, like a huge drop in performance or something. Anyone know?

    Read the article

  • Fastest bit-blit in C# ?

    - by AttackingHobo
    I know there is Unity, and XNA that both use C#, but I am don't know what else I could use. The reason I say C# is that the syntax and style is similar to AS3, which I am familiar with, and I want to choose the correct framework to start learning with. What should I use to be able to do the most possible bit-blit(direct pixel copy) objects per frame. EDIT: I should not need to add this, but I am looking for the most possible amount of objects per frame because I am making a few Bullet-Hell SHMUPS. I need thousands and thousands of bullets, particles, and hundreds of enemies on the screen at once. I am looking for a solution to do as many bit-blit operations per frame, I am not looking for a general purpose engine. EDIT2: I want bit-blitting because I do not want to exclude people who have lower end video cards but a fast processor from playing my games.

    Read the article

  • Adding tolerance to a point in polygon test

    - by David Gouveia
    I've been using this method which was taken from Game Coding Complete to detect whether a point is inside of a polygon. It works in almost every case, but is failing on a few edge cases, and I can't figure out the reason. For example, given a polygon with vertices at (0,0) (0,100) and (100,100), the algorithm is returning: True for any point strictly inside the polygon False for any of the vertices False for (0, 50) which lies on one of the edges of the polygon True (?) for (50,50) which is also on one of the edges of the polygon I'd actually like to relax the algorithm so that it returns true in all of these cases. In other words, it should return true for points that are strictly inside, for the vertices themselves, and for points on the edges of the polygon. If possible I'd also like to give it enough tolerance so that it always tend towards "true" in face of floating point fluctuations. For example, I have another method, that given a line segment and a point, returns the closest location on the line segment to the given point. Currently, given any point outside the polygon and one of its edges, there are cases where the result is categorized as being inside by the method above, while other points are considered outside. I'd like to give it enough tolerance so that it always returns true in this situation. The way I've currently solved the problem is an hack, which consists of using an external library to inflate the polygon by a few pixels, and performing the tests on the inflated polygon, but I'd really like to replace this with a proper solution.

    Read the article

  • Set a drawing viewport while using camera

    - by Mariano
    I'm working with XNA. I already have a basic world made of tiles and a camera using a transform matrix. I have a character moving around and the camera follows. What I want to do now is draw the map only on a certain part of the screen as shown on the figure below. This way I can move the map to the left of the screen and have the other fixed parts shift to the right. Do I need to modify the camera matrix? Make a new viewport?

    Read the article

  • Scrolling Box2D DebugDraw

    - by onedayitwillmake
    I'm developing a game using Box2D (javascript implementation - Box2DWeb), and I would like to know how I can pan the debug draw. I know the usual answer is - don't use debug draw, it's just for debugging. I'm not, however not all my objects are on the same screen, and i'd like to see where they are in the physics representation. How can I pan the debug drawing? As you can see the debug draw stuff, is show on the top left, but it only shows a small part of the world. Here is an example of what I mean: http://onedayitwillmake.com/ChuClone/ The game is open source, If you'd like to poke through and note something that perhaps i'm doing something that is obviously wrong: https://github.com/onedayitwillmake/ChuClone Here's my hacky way that I'm using now to scroll the b2DebugDraw view, in which I added a property offsetX and offsetY into b2DebugDraw

    Read the article

  • Finding shapes in 2D Array, then optimising

    - by assemblism
    I'm new so I can't do an image, but below is a diagram for a game I am working on, moving bricks into patterns, and I currently have my code checking for rotated instances of a "T" shape of any colour. The X and O blocks would be the same colour, and my last batch of code would find the "T" shape where the X's are, but what I wanted was more like the second diagram, with two "T"s Current result      Desired Result [X][O][O]                [1][1][1] [X][X][_]                [2][1][_] [X][O][_]                [2][2][_] [O][_][_]                [2][_][_] My code loops through x/y, marks blocks as used, rotates the shape, repeats, changes colour, repeats. I have started trying to fix this checking with great trepidation. The current idea is to: loop through the grid and make note of all pattern occurrences (NOT marking blocks as used), and putting these to an array loop through the grid again, this time noting which blocks are occupied by which patterns, and therefore which are occupied by multiple patterns. looping through the grid again, this time noting which patterns obstruct which patterns That much feels right... What do I do now? I think I would have to try various combinations of conflicting shapes, starting with those that obstruct the most other patterns first.How do I approach this one? use the rational that says I have 3 conflicting shapes occupying 8 blocks, and the shapes are 4 blocks each, therefore I can only have a maximum of two shapes. (I also intend to incorporate other shapes, and there will probably be score weighting which will need to be considered when going through the conflicting shapes, but that can be another day) I don't think it's a bin packing problem, but I'm not sure what to look for. Hope that makes sense, thanks for your help

    Read the article

  • New to CG shader programming, what program should I use to write and test them?

    - by Notbad
    I have started witting some shaders. First ones were fairly easy to write in notepad but now I need something with a bit more meat. I have checked rendermonnkey that seems to support CG but it is really old and don't know if it is a good option. On the other hand there exist this FX Composer 2.0 but it seems somthing that could really distract me from learning shaders because it seems a pretty deep program. Are there any other possibilities? There's a really nice alternative to write shaders named ShaderToy but just supports GLSL. Any information will be really welcomed. Thanks in advance.

    Read the article

  • Is there any way to enable the HiDef graphics profile property on a Silverlight 5 3d Web App?

    - by Daniel
    I have an XNA Windows Game that uses the HiDef profile to load complex fbx and obj files. Trying to move it over to a Silverlight 3d Web App, Silverlight seems to only want to use the Reach profile, and I get an error that the Reach profile does not support a sufficient number of primitive draws per call. Is there any way to change to HiDef in Silverlight 5? It is not in the project properties and attempting to change it in mainpage.xaml.cs only gives me the option of setting it to Reach.

    Read the article

  • Frame timing for GLFW versus GLUT

    - by linello
    I need a library which ensures me that the timing between frames are more constant as possible during an experiment of visual psychophics. This is usually done synchronizing the refresh rate of the screen with the main loop. For example if my monitor runs at 60Hz I would like to specify that frequency to my framework. For example if my gameloop is the following void gameloop() { // do some computation printDeltaT(); Flip buffers } I would like to have printed a constant time interval. Is it possible with GLFW?

    Read the article

  • In a state machine, is it a good idea to separate states and transitions?

    - by codablank1
    I have implemented a small state machine in this way (in pseudo code): class Input {} class KeyInput inherits Input { public : enum { Key_A, Key_B, ..., } } class GUIInput inherits Input { public : enum { Button_A, Button_B, ..., } } enum Event { NewGame, Quit, OpenOptions, OpenMenu } class BaseState { String name; Event get_event (Input input); void handle (Event e); //event handling function } class Menu inherits BaseState{...} class InGame inherits BaseState{...} class Options inherits BaseState{...} class StateMachine { public : BaseState get_current_state () { return current_state; } void add_state (String name, BaseState state) { statesMap.insert(name, state);} //raise an exception if state not found BaseState get_state (String name) { return statesMap.find(name); } //raise an exception if state or next_state not found void add_transition (Event event, String state_name, String next_state_name) { BaseState state = get_state(state_name); BaseState next_state = get_state(next_state_name); transitionsMap.insert(pair<event, state>, next_state); } //raise exception if couple not found BaseState get_next_state(Event event, BaseState state) { return transitionsMap.find(pair<event, state>); } void handle(Input input) { Event event = current_state.get_event(input) current_state.handle(event); current_state = get_next_state(event, current_state); } private : BaseState current_state; map<String, BaseState> statesMap; //map of all states in the machine //for each couple event/state, this map stores the next state map<pair<Event, BaseState>, BaseState> transitionsMap; } So, before getting the transition, I need to convert the key input or GUI input to the proper event, given the current state; thus the same key 'W' can launch a new game in the 'Menu' state or moving forward a character in the 'InGame' state; Then I get the next state from the transitionsMap and I update the current state Does this configuration seem valid to you ? Is it a good idea to separate states and transitions ? And I have some kind of trouble to represent a 'null state' or a 'null event'; What initial value can I give to the current state and which one should be returned by get_state if it fails ?

    Read the article

  • Dynamic libraries are not allowed on iOS but what about this?

    - by tapirath
    I'm currently using LuaJIT and its FFI interface to call C functions from LUA scripts. What FFI does is to look at dynamic libraries' exported symbols and let the developer use it directly form LUA. Kind of like Python ctypes. Obviously using dynamic libraries is not permitted in iOS for security reasons. So in order to come up with a solution I found the following snippet. /* (c) 2012 +++ Filip Stoklas, aka FipS, http://www.4FipS.com +++ THIS CODE IS FREE - LICENSED UNDER THE MIT LICENSE ARTICLE URL: http://forums.4fips.com/viewtopic.php?f=3&t=589 */ extern "C" { #include <lua.h> #include <lualib.h> #include <lauxlib.h> } // extern "C" #include <cassert> // Please note that despite the fact that we build this code as a regular // executable (exe), we still use __declspec(dllexport) to export // symbols. Without doing that FFI wouldn't be able to locate them! extern "C" __declspec(dllexport) void __cdecl hello_from_lua(const char *msg) { printf("A message from LUA: %s\n", msg); } const char *lua_code = "local ffi = require('ffi') \n" "ffi.cdef[[ \n" "const char * hello_from_lua(const char *); \n" // matches the C prototype "]] \n" "ffi.C.hello_from_lua('Hello from LUA!') \n" // do actual C call ; int main() { lua_State *lua = luaL_newstate(); assert(lua); luaL_openlibs(lua); const int status = luaL_dostring(lua, lua_code); if(status) printf("Couldn't execute LUA code: %s\n", lua_tostring(lua, -1)); lua_close(lua); return 0; } // output: // A message from LUA: Hello from LUA! Basically, instead of using a dynamic library, the symbols are exported directly inside the executable file. The question is: is this permitted by Apple? Thanks.

    Read the article

< Previous Page | 516 517 518 519 520 521 522 523 524 525 526 527  | Next Page >