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  • Algorithm to find average position

    - by Simran kaur
    In the given diagram, I have the extreme left and right points, that is -2 and 4 in this case. So, obviously, I can calculate the width which is 6 in this case. What we know: The number of partitions:3 in this case The partition number at at any point i.e which one is 1st,second or third partition (numbered starting from left) What I want: The position of the purple line drawn which is positio of average of a particular partition So, basically I just want a generalized formula to calculate position of the average at any point.

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  • How to I get a rotated sprite to move left or right?

    - by rphello101
    Using Java/Slick 2D, I'm using the mouse to rotate a sprite on the screen and the directional keys (in this case, WASD) to move the spite. Forwards and backwards is easy, just position += cos(ang)*speed or position -= cos(ang)*speed. But how do I get the sprite to move left or right? I'm thinking it has something to do with adding 90 degrees to the angle or something. Any ideas? Rotation code: int mX = Mouse.getX(); int mY = HEIGHT - Mouse.getY(); int pX = sprite.x+sprite.image.getWidth()/2; int pY = sprite.y+sprite.image.getHeight()/2; double mAng; if(mX!=pX){ mAng = Math.toDegrees(Math.atan2(mY - pY, mX - pX)); if(mAng==0 && mX<=pX) mAng=180; } else{ if(mY>pY) mAng=90; else mAng=270; } sprite.angle = mAng; sprite.image.setRotation((float) mAng); And the movement code (delta is change in time): Input input = gc.getInput(); Vector2f direction = new Vector2f(); Vector2f velocity = new Vector2f(); direction.x = (float) Math.cos(Math.toRadians(sprite.angle)); direction.y = (float) Math.sin(Math.toRadians(sprite.angle)); if(direction.length()>0) direction = direction.normalise(); //On a separate note, what does this line of code do? velocity.x = (float) (direction.x * sprite.moveSpeed); velocity.y = (float) (direction.y * sprite.moveSpeed); if(input.isKeyDown(sprite.up)){ sprite.x += velocity.x*delta; sprite.y += velocity.y*delta; }if (input.isKeyDown(sprite.down)){ sprite.x -= velocity.x*delta; sprite.y -= velocity.y*delta; }if (input.isKeyDown(sprite.left)){ //??? }if (input.isKeyDown(sprite.right)){ //??? }

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  • Mobile 3D engine renders alpha as full-object transparency

    - by Nils Munch
    I am running a iOS project using the isgl3d framework for showing pod files. I have a stylish car with 0.5 alpha windows, that I wish to render on a camera background, seeking some augmented reality goodness. The alpha on the windows looks okay, but when I add the object, I notice that it renders the entire object transparently, where the windows are. Including interior of the car. Like so (in example, keyboard can be seen through the dashboard, seats and so on. should be solid) The car interior is a seperate object with alpha 1.0. I would rather not show a "ghost car" in my project, but I haven't found a way around this. Have anyone encountered the same issue, and eventually reached a solution ?

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  • Ragdoll continuous movement

    - by Siddharth
    I have created a ragdoll for my game but the problem I found was that the ragdoll joints are not perfectly implemented so they are continuously moving. Ragdoll does not stand at fix place. I here paste my work for that and suggest some guidance about that so that it can stand on fix place. chest = new Chest(pX, pY, gameObject.getmChestTextureRegion(), gameObject); head = new Head(pX, pY - 16, gameObject.getmHeadTextureRegion(), gameObject); leftHand = new Hand(pX - 6, pY + 6, gameObject.getmHandTextureRegion() .clone(), gameObject); rightHand = new Hand(pX + 12, pY + 6, gameObject .getmHandTextureRegion().clone(), gameObject); rightHand.setFlippedHorizontal(true); leftLeg = new Leg(pX, pY + 18, gameObject.getmLegTextureRegion() .clone(), gameObject); rightLeg = new Leg(pX + 7, pY + 18, gameObject.getmLegTextureRegion() .clone(), gameObject); rightLeg.setFlippedHorizontal(true); gameObject.getmScene().registerTouchArea(chest); gameObject.getmScene().attachChild(chest); gameObject.getmScene().registerTouchArea(head); gameObject.getmScene().attachChild(head); gameObject.getmScene().registerTouchArea(leftHand); gameObject.getmScene().attachChild(leftHand); gameObject.getmScene().registerTouchArea(rightHand); gameObject.getmScene().attachChild(rightHand); gameObject.getmScene().registerTouchArea(leftLeg); gameObject.getmScene().attachChild(leftLeg); gameObject.getmScene().registerTouchArea(rightLeg); gameObject.getmScene().attachChild(rightLeg); // head revolute joint revoluteJointDef = new RevoluteJointDef(); revoluteJointDef.enableLimit = true; revoluteJointDef.initialize(head.getHeadBody(), chest.getChestBody(), chest.getChestBody().getWorldCenter()); revoluteJointDef.localAnchorA.set(0f, 0f); revoluteJointDef.localAnchorB.set(0f, -0.5f); revoluteJointDef.lowerAngle = (float) (0f / (180 / Math.PI)); revoluteJointDef.upperAngle = (float) (0f / (180 / Math.PI)); headRevoluteJoint = (RevoluteJoint) gameObject.getmPhysicsWorld() .createJoint(revoluteJointDef); // // left leg revolute joint revoluteJointDef.initialize(leftLeg.getLegBody(), chest.getChestBody(), chest.getChestBody().getWorldCenter()); revoluteJointDef.localAnchorA.set(0f, 0f); revoluteJointDef.localAnchorB.set(-0.15f, 0.75f); revoluteJointDef.lowerAngle = (float) (0f / (180 / Math.PI)); revoluteJointDef.upperAngle = (float) (0f / (180 / Math.PI)); leftLegRevoluteJoint = (RevoluteJoint) gameObject.getmPhysicsWorld() .createJoint(revoluteJointDef); // right leg revolute joint revoluteJointDef.initialize(rightLeg.getLegBody(), chest.getChestBody(), chest.getChestBody().getWorldCenter()); revoluteJointDef.localAnchorA.set(0f, 0f); revoluteJointDef.localAnchorB.set(0.15f, 0.75f); revoluteJointDef.lowerAngle = (float) (0f / (180 / Math.PI)); revoluteJointDef.upperAngle = (float) (0f / (180 / Math.PI)); rightLegRevoluteJoint = (RevoluteJoint) gameObject.getmPhysicsWorld() .createJoint(revoluteJointDef); // left hand revolute joint revoluteJointDef.initialize(leftHand.getHandBody(), chest.getChestBody(), chest.getChestBody().getWorldCenter()); revoluteJointDef.localAnchorA.set(0f, 0f); revoluteJointDef.localAnchorB.set(-0.25f, 0.1f); revoluteJointDef.lowerAngle = (float) (0f / (180 / Math.PI)); revoluteJointDef.upperAngle = (float) (0f / (180 / Math.PI)); leftHandRevoluteJoint = (RevoluteJoint) gameObject.getmPhysicsWorld() .createJoint(revoluteJointDef); // right hand revolute joint revoluteJointDef.initialize(rightHand.getHandBody(), chest.getChestBody(), chest.getChestBody().getWorldCenter()); revoluteJointDef.localAnchorA.set(0f, 0f); revoluteJointDef.localAnchorB.set(0.25f, 0.1f); revoluteJointDef.lowerAngle = (float) (0f / (180 / Math.PI)); revoluteJointDef.upperAngle = (float) (0f / (180 / Math.PI)); rightHandRevoluteJoint = (RevoluteJoint) gameObject.getmPhysicsWorld() .createJoint(revoluteJointDef);

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  • Collision filtering techniques

    - by Griffin
    I was wondering what efficient techniques are out there for mapping collision filtering between various bodies, sub-bodies, and so forth. I'm familiar with the simple idea of having different layers of 2D bodies, but this is not sufficient for more complex mapping: (Think of having sub-bodies of a body, such as limbs, collide with each other by placing them on the same layer, and then wanting to only have the legs collide with the ground while the arms would not) This can be solved with a multidimensional layer setup, but I would probably end up just creating more and more layers to the point where the simplicity and efficiency of layer filtering would be gone. Are there any more complex ways to solve even more complex situations than this?

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  • Inverting matrix then decomposing gives different quaternion than decomposing then inverting the quat

    - by Fraser
    I'm getting different signs when I convert a matrix to quaternion and invert that, versus when I invert a matrix and then get the quaternion from it: Quaternion a = Quaternion.Invert(getRotation(m)); Quaternion b = getRotation(Matrix.Invert(m)); I would expect a and b to be identical (or inverses of each other). However, it looks like q1 = (x, y, -z, -w) while q2 = (-x, -y, w, z). In other words, the Z and W components have been switched for some reason. Note: getRotation() decomposes the transform matrix and returns just the rotation part of it (I've tried normalizing the result; it does nothing). The matrix m is a complete transform matrix and contains a translation (and possibly a scale) as well as a rotation. I'm using D3DXMatrixDecompose to do the actual decomposition.

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  • How to make unit selection circles merge?

    - by MaT
    I would like to know how to make this effect of merged circle selection. Here are images to illustrate: Basically I'm looking for this effect: How the merge effect of the circles can be achieved ? I didn't found any explanation concerning this effect. I know that to project those texture I can develop a decal system but I don't know how to create the merging effect. If possible, I'm looking for purely shaders solution.

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  • Fastest way to group units that can see each other?

    - by mac
    In the 2D game I'm working with, the game engine is able to give me, for each unit, the list of other units that are in its view range. I would like to know if there is an established algorithm to sort the units in groups, where each group would be defined by all those units which are "connected" to each other (even through others). An example might help understand the question better (E=enemy, O=own unit). First the data that I would get from the game engine: E1 can see E2, E3, O5 E2 can see E1 E3 can see E1 E4 can see O5 E5 can see O2 E6 can see E7, O9, O1 E7 can see E6 O1 can see E6 O2 can see O5, E5 O5 can see E1, E4, O2 O9 can see E6 Then I should compute the groups as follow: G1 = E1, E2, E3, E4, E5, O2, O5 G2 = O1, O9, E6, E7 It can be safely assumed that there is a transitive property for the field of view: [if A sees B, then B sees A]. Just to clarify: I already wrote a naïve implementation that loops on each row of the game engine info, but from the look of it, it seems a problem general enough for it to have been studied in depth and have various established algorithms (maybe passing through some tree-like structure?). My problem is that I couldn't find a way to describe my problem that returned useful google hits. Thank you in advance for your help!

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  • HLSL Pixel Shader that does palette swap

    - by derrace
    I have implemented a simple pixel shader which can replace a particular colour in a sprite with another colour. It looks something like this: sampler input : register(s0); float4 PixelShaderFunction(float2 coords: TEXCOORD0) : COLOR0 { float4 colour = tex2D(input, coords); if(colour.r == sourceColours[0].r && colour.g == sourceColours[0].g && colour.b == sourceColours[0].b) return targetColours[0]; return colour; } What I would like to do is have the function take in 2 textures, a default table, and a lookup table (both same dimensions). Grab the current pixel, and find the location XY (coords) of the matching RGB in the default table, and then substitute it with the colour found in the lookup table at XY. I have figured how to pass the Textures from C# into the function, but I am not sure how to find the coords in the default table by matching the colour. Could someone kindly assist? Thanks in advance.

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  • Increase animation speed according to the swipe speed in unity for Android

    - by rohit
    I have the animation done through Maya and brought the FBX file to unity. Here is my code to calculate the speed of the swipe: Vector2 speedMeasuredInScreenWidthsPerSecond =(Input.touches[0].deltaPosition / Screen.width) * Input.touches[0].deltaTime; Now I wanted to take speedMeasuredInScreenWidthsPerSecond and use it to increase the animation speed accordingly like this: animation["gmeChaAnimMiddle"].speed=Mathf.Round(speedMeasuredInScreenWidthsPerSecond); However, this results in an error that I need to convert Vector2 to float. So how do I overcome it?

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  • Velocity control of the player, why doesn't this work?

    - by Dominic Grenier
    I have the following code inside a while True loop: if abs(playerx) < MAXSPEED: if moveLeft: playerx -= 1 if moveRight: playerx += 1 if abs(playery) < MAXSPEED: if moveDown: playery += 1 if moveUp: playery -= 1 if moveLeft == False and abs(playerx) > 0: playerx += 1 if moveRight == False and abs(playerx) > 0: playerx -= 1 if moveUp == False and abs(playery) > 0: playery += 1 if moveDown == False and abs(playery) > 0: playery -= 1 player.x += playerx player.y += playery if player.left < 0 or player.right > 1000: player.x -= playerx if player.top < 0 or player.bottom > 600: player.y -= playery The intended result is that while an arrow key is pressed, playerx or playery increments by one at every iteration until it reaches MAXSPEED and stays at MAXSPEED. And that when the player stops pressing that arrow key, his speed decreases until it reaches 0. To me, this code explicitly says that... But what actually happens is that playerx or playery keeps incrementing regardless of MAXSPEED and continues moving even after the player stops pressing the arrow key. I keep rereading but I'm completely baffled by this weird behavior. Any insights? Thanks.

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  • Applying effects to an existing program that uses BasicEffect

    - by Fibericon
    Using the finished product from the tutorial here. Is it possible to apply the grayscale effect from here: Making entire scene fade to grayscale Or would you basically have to rewrite everything? EDIT: It's doing something now, but the whole grayscale seems extremely blue. It's like I'm looking at it through dark blue sunglasses. Here's my draw function: protected override void Draw(GameTime gameTime) { device.SetRenderTarget(renderTarget); graphics.GraphicsDevice.Clear(Color.CornflowerBlue); //Drawing models, bullets, etc. device.SetRenderTarget(null); spriteBatch.Begin(0, BlendState.Additive, SamplerState.PointWrap, DepthStencilState.Default, RasterizerState.CullNone, grayScale); Texture2D temp = (Texture2D)renderTarget; grayScale.Parameters["coloredTexture"].SetValue(temp); grayScale.CurrentTechnique = grayScale.Techniques["Grayscale"]; foreach (EffectPass pass in grayScale.CurrentTechnique.Passes) { pass.Apply(); } spriteBatch.Draw(temp, new Vector2(GraphicsDevice.PresentationParameters.BackBufferWidth/2, GraphicsDevice.PresentationParameters.BackBufferHeight/2), null, Color.White, 0f, new Vector2(renderTarget.Width/2, renderTarget.Height/2), 1.0f, SpriteEffects.None, 0f); spriteBatch.End(); base.Draw(gameTime); } Another edit: figured out what I was doing wrong. I have Blendstate.Additive in the spriteBatch.Draw() call. It should be Blendstate.Opaque, or it literally tries to add the blank blue image to the grayscale image.

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  • Collision detection of convex shapes on voxel terrain

    - by Dave
    I have some standard convex shapes (cubes, capsules) on a voxel terrain. It is very easy to detect single vertex collisions. However, it becomes computationally expensive when many vertices are involved. To clarify, currently my algorithm represents a cube as multiple vertices covering every face of the cube, not just the corners. This is because the cubes can be much bigger than the voxels, so multiple sample points (vertices) are required (the distance between sample points must be at least the width of a voxel). This very rapidly becomes intractable. It would be great if there were some standard algorithm(s) for collision detection between convex shapes and arbitrary voxel based terrain (like there is with OBB's and seperating axis theorem etc). Any help much appreciated.

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  • How are these bullets done?

    - by Mike
    I really want to know how the bullets in Radiangames Inferno are done. The bullets seem like they are just billboard particles but I am curious about how their tails are implemented. They can curve so this means they are not just a billboard. Also, they appear continuous which implies that the tails are not made of a bunch of smaller particles (I think). Can anyone shead some light on this for me?

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  • How to implement efficient Fog of War?

    - by Cambrano
    I've asked a question how to implement Fog Of War(FOW) with shaders. Well I've got this working. I use the vertex color to identify the alpha of a single vertex. I guess the most of you know what the FOW of Age of Empires was like, anyway I'll shortly explain it: You have a map. Everything is unexplored(solid black / 100% transparency) at the beginning. When your NPC's / other game units explore the world (by moving around mostly) they unshadow the map. That means. Everything in a specific radius (viewrange) around a NPC is visible (0%transparency). Anything that is out of viewrange but already explored is visible but shadowed (50% transparency). So yeah, AoE had relatively huge maps. Requirements was something around 100mhz etc. So it should be relatively easy to implement something to solve this problem - actually. Okay. I'm currently adding planes above my world and set the color per vertex. Why do I use many planes ? Unity has a vertex limit of 65.000 per mesh. According to the size of my tiles and the size of my map I need more than one plane. So I actually need a lot of planes. This is obviously pita for my FPS. Well so my question is, what are simple (in sense of performance) techniques to implement a FOW shader? Okay some simplified code what I'm doin so far: // Setup for (int x = 0; x < (Map.Dimension/planeSize); x++) { for (int z = 0; z < (Map.Dimension/planeSize); z++) { CreateMeshAt(x*planeSize, 3, z*planeSize) } } // Explore (is called from NPCs when walking for example) for (int x = ((int) from.x - radius); x < from.x + radius; x ++) { for (int z = ((int) from.z - radius); z < from.z + radius; z ++) { if (from.Distance(x, 1, z) > radius) continue; _transparency[x/tileSize, z/tileSize] = 0.5f; } } // Update foreach(GameObject plane in planes){ foreach(Vector3 vertex in vertices){ Vector3 worldPos = GetWorldPos(vertex); vertex.Color = new Color(0,0,0, _transparency[worldPos.x/tileSize, worldPos.z/tileSize]); } } My shader just sets the transparency of the vertex now, which comes from the vertex color channel

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  • Corona SDK: Quality of support and resources?

    - by Nick Wiggill
    I've not used Corona SDK before and am looking into it for a friend. (He is also considering Unity.) I wonder what the support is like for Corona? While Unity has a great many customers and so the Unity team can often not address issues directly, the community at large is very helpful and there are many excellent resources: tutorials, forum posts, code resources. What is Corona like in this regard, and by comparison?

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  • Basic Connections Through Socket Server

    - by Walrus
    I'm designing a simple 2 player RTS with Stencyl, a program that uses blocks for coding. The current code updates lists whenever an actor moves (new X and Y), and I'd want the server to update the game state with each change to the list. However, to start off: I don't even know how to set up a socket server. Stencyl has taught me the basics of logic, but I've yet to learn any programming languages. I've downloaded a Smartfox 2X socket server that I'm intending to use. Right now I'm only looking to make baby steps; I want to do something to this effect: "When someone connects to the server, open insert file here". How can I do this? My intention is to have this file be the game client. Is this "open file when connected" method the best way to go about this? When answering: assume that I know nothing, because really, though I have done research (I know that UDPTCP for real time), implementation-wise I know nothing.

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  • Does md2 support skeletal meshes?

    - by jsvcycling
    I'm creating an FPS game. I'm writing my own game engine. So far all the backend stuff is going great. I'd like to support md2 as the native file format for 3D Objects, but I also want to use skeletal meshes. Does anyone know if the md2 file format supports skeletal meshes? In-case you need to know, I'm going to use blender as my Mesh creation tool and C++ as my programming language... Thanks For got to mention, the engine is based on OpenGL... Alright, for anyone who is reading this, I just found the Doom 3 md5 specifications (http://tfc.duke.free.fr/coding/md5-specs-en.html). It gives you some help on writing a parser (see bottom of link), but the example doesn't support lighting and texture mapping (the second set of example code allows for animation). Thanks @Neverender for answering my question...

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  • General visual effects to meshes/entities

    - by Pacha
    I am trying to add some visual effects to some entities, meshes, or whatever you want to call them as they are looking pretty dull in my game right now. What I want to achieve is this: http://youtu.be/zox8935PLw0?t=36s (the "texture" gets disintegrated and then goes back to normal, covering the whole mesh.) Also I would like to know what is the best way to add effects like the one in the video to my game (for example, thunder effects, shattering, etc.) I know that I can do some things with shaders, but I haven't learned them too well and I am still in a beginner level. I am using Ogre3D, and GLSL for shaders. Thanks! Note: this is a screen-shot of my game, I want to apply the effect in the video to my main character):

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  • Game physics / 2D Collision detection AS3

    - by Jery
    I know there are some methods you can use like hittestPoint and so on, but I want to see where my movieclip colliedes with another another movieclip. Any other methods I can use? by any chance does somebody know some a good introduction to game physics? Im asking because I coded a small engine and pretty much the whole code is spagetti code thats why I would like to know how you can setup something like this properly

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  • Sprites as Actors

    - by Scán
    Hello, I'm not experienced in GameDev questions, but as a programmer. In the language Scala, you can have scalable multi-tasking with Actors, very stable, as I hear. You can even habe hundreds of thousands of them running at once without a problem. So I thought, maybe you can use these as a base class for 2D-Sprites, to break out of the game-loop thing that requires to go through all the sprites and move them. They'd basically move themselves, event-driven. Would that make sense for a game? Having it multitasked like that? After all, it will run on the JVM, though that should not be much of a problem nowadays.

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  • How to balance a non-symmetric "extension" based game?

    - by Klaim
    Most strategy games have fixed units and possible behaviours. However, think of a game like Magic The Gathering : each card is a set of rules. Regularly, new sets of card types are created. I remember that the firsts editions of the game have been said to be prohibited in official tournaments because the cards were often too powerful. Later extensions of the game provided more subtle effects/rules in cards and they managed to balance the game apparently effectively, even if there is thousands of different cards possible. I'm working on a strategy game that is a bit in the same position : every units are provided by extensions and the game is thought to be extended for some years, at least. The effects variety of the units are very large even with some basic design limitations set to be sure it's manageable. Each player choose a set of units to play with (defining their global strategy) before playing (like chooseing a themed deck of Magic cards). As it's a strategy game (you can think of Magic as a strategy game too in some POV), it's essentially skirmish based so the game have to be fair, even if the players don't choose the same units before starting to play. So, how do you proceed to balance this type of non-symmetric (strategy) game when you know it will always be extended? For the moment, I'm trying to apply those rules but I'm not sure it's right because I don't have enough design experience to know : each unit would provide one unique effect; each unit should have an opposite unit that have an opposite effect that would cancel each others; some limitations based on the gameplay; try to get a lot of beta tests before each extension release? Looks like I'm in the most complex case?

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  • Is it important for reflection-based serialization maintain consistent field ordering?

    - by Matchlighter
    I just finished writing a packet builder that dynamically loads data into a data stream for eventual network transmission. Each builder operates by finding fields in a given class (and its superclasses) that are marked with a @data annotation. When I finishing my implementation, I remembered that getFields() does not return results in any specific order. Should reflection-based methods for serializing arbitrary data (like my packets) attempt to preserve a specific field ordering (such as alphabetical), and if so, how?

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  • Registering InputListener in libGDX

    - by JPRO
    I'm just getting started with libGDX and have run into a snag registering an InputListener for a button. I've gone through many examples and this code appears correct to me but the associated callback never triggers ("touched" is not printed to console). I'm just posting the code with the abstract game screen and the implementing screen. The application starts successfully with a label of "Exit" in the bottom left hand corner, but clicking the button/label does nothing. I'm guessing the fix is something simple. What am I overlooking? public abstract class GameScreen<T> implements Screen { protected final T game; protected final SpriteBatch batch; protected final Stage stage; public GameScreen(T game) { this.game = game; this.batch = new SpriteBatch(); this.stage = new Stage(0, 0, true); } @Override public final void render(float delta) { update(delta); // Clear the screen with the given RGB color (black) Gdx.gl.glClearColor(0f, 0f, 0f, 1f); Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT); stage.act(delta); stage.draw(); } public abstract void update(float delta); @Override public void resize(int width, int height) { stage.setViewport(width, height, true); } @Override public void show() { Gdx.input.setInputProcessor(stage); } // hide, pause, resume, dipose } public class ExampleScreen extends GameScreen<MyGame> { private TextButton exitButton; public ExampleScreen(MyGame game) { super(game); } @Override public void show() { super.show(); TextButton.TextButtonStyle buttonStyle = new TextButton.TextButtonStyle(); buttonStyle.font = Font.getFont("Origicide", 32); buttonStyle.fontColor = Color.WHITE; exitButton = new TextButton("Exit", buttonStyle); exitButton.addListener(new InputListener() { @Override public void touchUp (InputEvent event, float x, float y, int pointer, int button) { System.out.println("touched"); } }); stage.addActor(exitButton); } @Override public void update(float delta) { } }

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  • How to use shared_ptr for COM interface pointers

    - by Seefer
    I've been reading about various usage advice relating to the new c++ standard smart pointers unique_ptr, shared_ptr and weak_ptr and generally 'grok' what they are about when I'm writing my own code that declares and consumes them. However, all the discussions I've read seem restricted to this simple usage situation where the programmer is using smart in his/her own code, with no real discussion on techniques when having to work with libraries that expect raw pointers or other types of 'smart pointers' such as COM interface pointers. Specifically I'm learning my way through C++ by attempting to get a standard Win32 real-time game loop up and running that uses Direct2D & DirectWrite to render text to the display showing frames per second. My first task with Direct2D is in creating a Direct2D Factory object with the following code from the Direct2D examples on MSDN: ID2D1Factory* pD2DFactory = nullptr; HRESULT hr = D2D1CreateFactory(D2D1_FACTORY_TYPE_SINGLE_THREADED, &pD2DFactory); pD2DFactory is obviously an 'out' parameter and it's here where I become uncertain how to make use of smart pointers in this context, if indeed it's possible. My inexperienced C++ mind tells me I have two problems: With pD2DFactory being a COM interface pointer type, how would smart_ptr work with the Add() / Release() member functions for a COM object instance? Are smart pointers able to be passed to functions in situations where the function is using an 'out' pointer parameter technique? I did experiment with the alternative of using _com_ptr_t in the comip.h header file to help with pointer lifetime management and declared the pD2DFactory pointer with the following code: _com_ptr_t<_com_IIID<pD2DFactory, &__uuidof(pD2DFactory)>> pD2DFactory = nullptr; and it appears to work so far but, as you can see, the syntax is cumbersome :) So, I was wondering if any C++ gurus here could confirm whether smart pointers are able to help in cases like this and provide examples of usage, or point me to more in-depth discussions of smart pointer usage when needing to work with other code libraries that know nothing of them. Or is it simply a case of my trying to use the wrong tool for the job? :)

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