Search Results

Search found 26124 results on 1045 pages for 'unreal development kit'.

Page 407/1045 | < Previous Page | 403 404 405 406 407 408 409 410 411 412 413 414  | Next Page >

  • Workflow with Flash Pro CS6 and FlashDevelop: Using fla and swc to store assets

    - by Arthur Wulf White
    I am using this tutorial: http://www.flashdevelop.org/wikidocs/index.php?title=AS3:FlexAndFlashCS3Workflow In the past older versions of Flash Pro I was able to complete these steps: right-click on the symbol in the Library panel, select "Linkage..." dialog, check "Export for ActionScript" and fill in the symbol name (ie. MySymbol_design or assets.MySymbol_design), do not change the base class (ie. flash.display.MovieClip). Right now, I am stuck at that part. Any hints? What I wish to do is: Use fla for the artist to store assets. Publish to swc Extract the assets in FlashDevelop by creating an instance of their class. ... How is this done in CS6? To clear things up, this is what I see when I right click a Flash symbol:

    Read the article

  • Balancing game difficulty against player progression

    - by Raven Dreamer
    It seems that the current climate of games seems to cater to an obvious progression of player power, whether that means getting a bigger, more explosive gun in Halo, leveling up in an RPG, or unlocking new options in Command and Conquer 4. Yet this concept is not exclusive to video or computer games -- even in Dungeons and Dragons players can strive to acquire a +2 sword to replace the +1 weapon they've been using. Yet as a systems designer, the concept of player progression is giving me headache after headache. Should I balance around the players exact capabilities and give up on a simple linear progression? (I think ESIV:Oblivion is a good example of this) Is it better to throw the players into an "arms race" with their opponents, where if the players don't progress in an orderly manner, it is only a matter of time until gameplay is unbearably difficult? (4th Edition DnD strikes me as a good example of this) Perhaps it would make most sense to untether the core gameplay mechanics from progression at all -- give them flashier, more interesting (but not more powerful!) ways to grow?

    Read the article

  • Can I use DllImport/PInvoke in libraries loaded as Assets in Unity Free?

    - by sebf
    I am interested in using utilising third-party libraries in Unity Free. I know Unity can use managed libraries as Assets, but only the Pro version supports using native libraries. (DllImport within scripts). This thread however suggests that it is possible to import DLLs in the free version. I would like to utilise native libraries (as a hobbyist I cannot afford Pro), but want to do it the supported way so I don't have to worry about Unity 'fixing' this hole if that is what it is. Is there any supported way to use native libraries with Unity free? (i.e. does that thread suggest a workaround or is it a 'bug'? Is it supported to use DllImport/PInvoke in libraries loaded as assets? (could I create a wrapper myself?)

    Read the article

  • Shadow mapping: what is the light looking at?

    - by PgrAm
    I'm all set to set up shadow mapping in my 3d engine but there is one thing I am struggling to understand. The scene needs to be rendered from the light's point of view so I simply first move my camera to the light's position but then I need to find out which direction the light is looking. Since its a point light its not shining in any particular direction. How do I figure out what the orientation for the light point of view is?

    Read the article

  • Normal map applied as diffuse textures looks wrong

    - by KaiserJohaan
    Diffuse textures works fine, but I am having problem with normal maps, so I thought I'd tried to apply the normal maps as the diffuse map in my fragment shader so I could see everything is OK. I comment-out my normal map code and just set the diffuse map to the normal map and I get this: http://postimg.org/image/j9gudjl7r/ Looks like a smurf! This is the actual normal map of the main body: http://postimg.org/image/sbkyr6fg9/ Here is my fragment shader, notice I commented out normal map code so I could debug the normal map as a diffuse texture "#version 330 \n \ \n \ layout(std140) uniform; \n \ \n \ const int MAX_LIGHTS = 8; \n \ \n \ struct Light \n \ { \n \ vec4 mLightColor; \n \ vec4 mLightPosition; \n \ vec4 mLightDirection; \n \ \n \ int mLightType; \n \ float mLightIntensity; \n \ float mLightRadius; \n \ float mMaxDistance; \n \ }; \n \ \n \ uniform UnifLighting \n \ { \n \ vec4 mGamma; \n \ vec3 mViewDirection; \n \ int mNumLights; \n \ \n \ Light mLights[MAX_LIGHTS]; \n \ } Lighting; \n \ \n \ uniform UnifMaterial \n \ { \n \ vec4 mDiffuseColor; \n \ vec4 mAmbientColor; \n \ vec4 mSpecularColor; \n \ vec4 mEmissiveColor; \n \ \n \ bool mHasDiffuseTexture; \n \ bool mHasNormalTexture; \n \ bool mLightingEnabled; \n \ float mSpecularShininess; \n \ } Material; \n \ \n \ uniform sampler2D unifDiffuseTexture; \n \ uniform sampler2D unifNormalTexture; \n \ \n \ in vec3 frag_position; \n \ in vec3 frag_normal; \n \ in vec2 frag_texcoord; \n \ in vec3 frag_tangent; \n \ in vec3 frag_bitangent; \n \ \n \ out vec4 finalColor; " " \n \ \n \ void CalcGaussianSpecular(in vec3 dirToLight, in vec3 normal, out float gaussianTerm) \n \ { \n \ vec3 viewDirection = normalize(Lighting.mViewDirection); \n \ vec3 halfAngle = normalize(dirToLight + viewDirection); \n \ \n \ float angleNormalHalf = acos(dot(halfAngle, normalize(normal))); \n \ float exponent = angleNormalHalf / Material.mSpecularShininess; \n \ exponent = -(exponent * exponent); \n \ \n \ gaussianTerm = exp(exponent); \n \ } \n \ \n \ vec4 CalculateLighting(in Light light, in vec4 diffuseTexture, in vec3 normal) \n \ { \n \ if (light.mLightType == 1) // point light \n \ { \n \ vec3 positionDiff = light.mLightPosition.xyz - frag_position; \n \ float dist = max(length(positionDiff) - light.mLightRadius, 0); \n \ \n \ float attenuation = 1 / ((dist/light.mLightRadius + 1) * (dist/light.mLightRadius + 1)); \n \ attenuation = max((attenuation - light.mMaxDistance) / (1 - light.mMaxDistance), 0); \n \ \n \ vec3 dirToLight = normalize(positionDiff); \n \ float angleNormal = clamp(dot(normalize(normal), dirToLight), 0, 1); \n \ \n \ float gaussianTerm = 0.0; \n \ if (angleNormal > 0.0) \n \ CalcGaussianSpecular(dirToLight, normal, gaussianTerm); \n \ \n \ return diffuseTexture * (attenuation * angleNormal * Material.mDiffuseColor * light.mLightIntensity * light.mLightColor) + \n \ (attenuation * gaussianTerm * Material.mSpecularColor * light.mLightIntensity * light.mLightColor); \n \ } \n \ else if (light.mLightType == 2) // directional light \n \ { \n \ vec3 dirToLight = normalize(light.mLightDirection.xyz); \n \ float angleNormal = clamp(dot(normalize(normal), dirToLight), 0, 1); \n \ \n \ float gaussianTerm = 0.0; \n \ if (angleNormal > 0.0) \n \ CalcGaussianSpecular(dirToLight, normal, gaussianTerm); \n \ \n \ return diffuseTexture * (angleNormal * Material.mDiffuseColor * light.mLightIntensity * light.mLightColor) + \n \ (gaussianTerm * Material.mSpecularColor * light.mLightIntensity * light.mLightColor); \n \ } \n \ else if (light.mLightType == 4) // ambient light \n \ return diffuseTexture * Material.mAmbientColor * light.mLightIntensity * light.mLightColor; \n \ else \n \ return vec4(0.0); \n \ } \n \ \n \ void main() \n \ { \n \ vec4 diffuseTexture = vec4(1.0); \n \ if (Material.mHasDiffuseTexture) \n \ diffuseTexture = texture(unifDiffuseTexture, frag_texcoord); \n \ \n \ vec3 normal = frag_normal; \n \ if (Material.mHasNormalTexture) \n \ { \n \ diffuseTexture = vec4(normalize(texture(unifNormalTexture, frag_texcoord).xyz * 2.0 - 1.0), 1.0); \n \ // vec3 normalTangentSpace = normalize(texture(unifNormalTexture, frag_texcoord).xyz * 2.0 - 1.0); \n \ //mat3 tangentToWorldSpace = mat3(normalize(frag_tangent), normalize(frag_bitangent), normalize(frag_normal)); \n \ \n \ // normal = tangentToWorldSpace * normalTangentSpace; \n \ } \n \ \n \ if (Material.mLightingEnabled) \n \ { \n \ vec4 accumLighting = vec4(0.0); \n \ \n \ for (int lightIndex = 0; lightIndex < Lighting.mNumLights; lightIndex++) \n \ accumLighting += Material.mEmissiveColor * diffuseTexture + \n \ CalculateLighting(Lighting.mLights[lightIndex], diffuseTexture, normal); \n \ \n \ finalColor = pow(accumLighting, Lighting.mGamma); \n \ } \n \ else { \n \ finalColor = pow(diffuseTexture, Lighting.mGamma); \n \ } \n \ } \n"; Here is my wrapper around a texture OpenGLTexture::OpenGLTexture(const std::vector<uint8_t>& textureData, uint32_t textureWidth, uint32_t textureHeight, TextureFormat textureFormat, TextureType textureType, Logger& logger) : mLogger(logger), mTextureID(gNextTextureID++), mTextureType(textureType) { glGenTextures(1, &mTexture); CHECK_GL_ERROR(mLogger); glBindTexture(GL_TEXTURE_2D, mTexture); CHECK_GL_ERROR(mLogger); GLint glTextureFormat = (textureFormat == TextureFormat::TEXTURE_FORMAT_RGB ? GL_RGB : textureFormat == TextureFormat::TEXTURE_FORMAT_RGBA ? GL_RGBA : GL_RED); glTexImage2D(GL_TEXTURE_2D, 0, glTextureFormat, textureWidth, textureHeight, 0, glTextureFormat, GL_UNSIGNED_BYTE, &textureData[0]); CHECK_GL_ERROR(mLogger); glGenerateMipmap(GL_TEXTURE_2D); CHECK_GL_ERROR(mLogger); glBindTexture(GL_TEXTURE_2D, 0); CHECK_GL_ERROR(mLogger); } OpenGLTexture::~OpenGLTexture() { glDeleteBuffers(1, &mTexture); CHECK_GL_ERROR(mLogger); } And here is the sampler I create which is shared between Diffuse and normal textures // texture sampler setup glGenSamplers(1, &mTextureSampler); CHECK_GL_ERROR(mLogger); glSamplerParameteri(mTextureSampler, GL_TEXTURE_MAG_FILTER, GL_LINEAR); CHECK_GL_ERROR(mLogger); glSamplerParameteri(mTextureSampler, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST); CHECK_GL_ERROR(mLogger); glSamplerParameteri(mTextureSampler, GL_TEXTURE_WRAP_S, GL_REPEAT); CHECK_GL_ERROR(mLogger); glSamplerParameteri(mTextureSampler, GL_TEXTURE_WRAP_T, GL_REPEAT); CHECK_GL_ERROR(mLogger); glSamplerParameterf(mTextureSampler, GL_TEXTURE_MAX_ANISOTROPY_EXT, mCurrentAnisotropy); CHECK_GL_ERROR(mLogger); glUniform1i(glGetUniformLocation(mDefaultProgram.GetHandle(), "unifDiffuseTexture"), OpenGLTexture::TEXTURE_UNIT_DIFFUSE); CHECK_GL_ERROR(mLogger); glUniform1i(glGetUniformLocation(mDefaultProgram.GetHandle(), "unifNormalTexture"), OpenGLTexture::TEXTURE_UNIT_NORMAL); CHECK_GL_ERROR(mLogger); glBindSampler(OpenGLTexture::TEXTURE_UNIT_DIFFUSE, mTextureSampler); CHECK_GL_ERROR(mLogger); glBindSampler(OpenGLTexture::TEXTURE_UNIT_NORMAL, mTextureSampler); CHECK_GL_ERROR(mLogger); SetAnisotropicFiltering(mCurrentAnisotropy); The diffuse textures looks like they should, but the normal looks so wierd. Why is this?

    Read the article

  • How can I view an R32G32B32 texture?

    - by bobobobo
    I have a texture with R32G32B32 floats. I create this texture in-program on D3D11, using DXGI_FORMAT_R32G32B32_FLOAT. Now I need to see the texture data for debug purposes, but it will not save to anything but dds, showing the error in debug output, "Can't find matching WIC format, please save this file to a DDS". So, I write it to DDS but I can't open it now! The DirectX texture tool says "An error occurred trying to open that file". I know the texture is working because I can read it in the GPU and the colors seem correct. How can I view an R32G32B32 texture in an image viewer?

    Read the article

  • How do I generate terrain like that of Scorched Earth?

    - by alex
    Hi, I'm a web developer and I am keen to start writing my own games. For familiarity, I've chosen JavaScript and canvas element for now. I want to generate some terrain like that in Scorched Earth. My first attempt made me realise I couldn't just randomise the y value; there had to be some sanity in the peaks and troughs. I have Googled around a bit, but either I can't find something simple enough for me or I am using the wrong keywords. Can you please show me what sort of algorithm I would use to generate something in the example, keeping in mind that I am completely new to games programming (since making Breakout in 2003 with Visual Basic anyway)?

    Read the article

  • How can I generate a view or projection matrix for OpenGL 3.+

    - by Ken
    I'm transitioning from OpenGL 2 to OpenGL 3.+ and to GLSL 1.5. I'm trying to avoid using the deprecated features. My question how do we now generate the view or projection matrix. I was using the matrix stack to calculate the projection matrix for me; GLfloat ptr[16]; gluPerspective(...); glGetFloatv(GL_MODELVIEW_MATRIX, ptr); //then pass ptr via a uniform to the shader But obviously the matrix stack is deprecated. So this approach is not the best an option going forward. I have the 'Red Book', 7th ed, which covers 3.0 & 3.1 and it still uses the deprecated matrix functions in it's examples. I could write some utility-code myself to generate the matrices. But I don't want to re-invent this particular wheel, especially when this functionality is required for every 3D graphics program. What is the accepted way to generate world,view & projection matrices for OpenGL? Is there an emerging 'standard' library for this? Or is there some other hidden (to me) functionality in OpenGL/GLSL which I have overlooked?

    Read the article

  • Meaning of offset in pygame Mask.overlap methods

    - by Alan
    I have a situation in which two rectangles collide, and I have to detect how much did they collide so so I can redraw the objects in a way that they are only touching each others edges. It's a situation in which a moving ball should hit a completely unmovable wall and instantly stop moving. Since the ball sometimes moves multiple pixels per screen refresh, it it possible that it enters the wall with more that half its surface when the collision is detected, in which case i want to shift it position back to the point where it only touches the edges of the wall. Here is the conceptual image it: I decided to implement this with masks, and thought that i could supply the masks of both objects (wall and ball) and get the surface (as a square) of their intersection. However, there is also the offset parameter which i don't understand. Here are the docs for the method: Mask.overlap Returns the point of intersection if the masks overlap with the given offset - or None if it does not overlap. Mask.overlap(othermask, offset) -> x,y The overlap tests uses the following offsets (which may be negative): +----+----------.. |A | yoffset | +-+----------.. +--|B |xoffset | | : :

    Read the article

  • Pygame set_colorkey transparency issues

    - by Nathan Chowning
    I'm having a strange issue that I cannot seem to remedy. I am doing some prototyping with Pygame on a desktop running windows and a laptop running OS X. Both are running python v2.7.3 (installed via homebrew for the Macbook) and pygame v1.9.1. For transparency, I have been using set_colorkey with a transparency color of (255, 0, 255). Here is the applicable code: transColor = pygame.Color(255, 0, 255) image = pygame.image.load(playerPath + "idle.png").convert() image.set_colorkey(transColor) This works flawlessly on my windows machine. On my laptop, it does not work. It just shows the hideous magenta color. Here's the strange part. If I change the transColor to (0, 0, 0), all black pixels in my images are transparent. Has anyone run into this issue before?

    Read the article

  • Using 2D sprites and 3D models together

    - by Sweta Dwivedi
    I have gone through a few posts that talks about changing the GraphicsDevice.BlendState and GraphicsDevice.DepthStencilState (SpriteBatch & Render states). . however even after changing the states .. i cant see my 3D model on the screen.. I see the model for a second before i draw my video in the background. . Here is the code: case GameState.InGame: GraphicsDevice.Clear(Color.AliceBlue); spriteBatch.Begin(); if (player.State != MediaState.Stopped) { videoTexture = player.GetTexture(); } Rectangle screen = new Rectangle(GraphicsDevice.Viewport.X, GraphicsDevice.Viewport.Y, GraphicsDevice.Viewport.Width, GraphicsDevice.Viewport.Height); // Draw the video, if we have a texture to draw. if (videoTexture != null) { spriteBatch.Draw(videoTexture, screen, Color.White); if (Selected_underwater == true) { spriteBatch.DrawString(font, "MaxX , MaxY" + maxWidth + "," + maxHeight, new Vector2(400, 10), Color.Red); spriteBatch.Draw(kinectRGBVideo, new Rectangle(0, 0, 100, 100), Color.White); spriteBatch.Draw(butterfly, handPosition, Color.White); foreach (AnimatedSprite a in aSprites) { a.Draw(spriteBatch); } } if(Selected_planet == true) { spriteBatch.Draw(kinectRGBVideo, new Rectangle(0, 0, 100, 100), Color.White); spriteBatch.Draw(butterfly, handPosition, Color.White); spriteBatch.Draw(videoTexture,screen,Color.White); GraphicsDevice.BlendState = BlendState.Opaque; GraphicsDevice.DepthStencilState = DepthStencilState.Default; GraphicsDevice.SamplerStates[0] = SamplerState.LinearWrap; foreach (_3DModel m in Solar) { m.DrawModel(); } } spriteBatch.End(); break;

    Read the article

  • Help, i cant reference my vars!

    - by SystemNetworks
    I have a sub-class(let's call it sub) and it contains all the function of an object in my game. In my main class(Let's call it main), i connect my sub to main. (Example sub Code: s = new sub(); Then I put my sub function at the update method. Code: s.myFunc(); Becuase in my sub, i have booleans, integers, float and more. The problem is that I don't want to connect my main class to use my main's int, booleans and others. If i connect it, it will have a stack overflow. This is what I put in my sub: Code: package javagame; import org.newdawn.slick.GameContainer; import org.newdawn.slick.Graphics; import org.newdawn.slick.Input; import org.newdawn.slick.state.StateBasedGame; public class Armory { package javagame; import org.newdawn.slick.GameContainer; import org.newdawn.slick.Graphics; import org.newdawn.slick.Input; import org.newdawn.slick.state.StateBasedGame; public class Store { public Integer wood; public Float probePositionX; public Float probePositionY; public Boolean StoreOn; public Boolean darkBought; public Integer money; public Integer darkEnergy; public Integer lifeLeft; public Integer powerLeft; public void darkStores(GameContainer gc, StateBasedGame sbg, GameContainer gc2) { Input input1 = gc.getInput(); //Player need wood to enter(200) If not there will be an error. if(wood>=200) { //Enter Store! if(input1.isKeyDown(Input.KEY_Q)) { //Player must be in this cord! if((probePositionX>393 && probePositionX<555) && (probePositionY< 271 && probePositionY>171)) { //The Store is On StoreOn=true; } } } } } In my main (update function) I put: Code: s.darkBought = darkBought; s.darkEnergy = darkEnergy; s.lifeLeft = lifeLeft; s.money = money; s.powerLeft = powerLeft; s.probePositionX = probePositionX; s.probePositionY = probePositionY; s.StoreOn = StoreOn; s.wood = wood; s.darkStores(gc, sbg, gc); The problem is when I go to the place, and I press q, nothing shows up. It should show another image. Is there anything wrong???

    Read the article

  • Is there a global "low resolution" filter for OpenGL?

    - by Ian Henry
    I'm trying to learn a little about OpenGL, so I'm making a simple 2D game (with OpenTK), and so far it's coming along well. I thought it would be fun to give it that, for lack of a better word, retropixelated look of games from the early nineties. I figured it would be an easy thing to do -- simply draw everything at half its normal size and scale up with no anti-aliasing. But I can't find any resources on how to do this. I can set the min/mag filters of my textures to nearest and that works fine for my sprites, but I'm using lots of primitives and I'd like the effect to apply to them as well. The one idea I had was to draw everything at half size, then somehow copy the render buffer to a texture, then render that texture full-size, but I don't know how to do that, and it seems like there must be a better way. Can anyone help me out?

    Read the article

  • Are there any alternative JS ports of Box2D?

    - by Petteri Hietavirta
    I have been thinking about creating a top down 2D car game for HTML5. For my first game I wrote the physics and collisions my self but for this one I would like to use some ready made library. I found out Box2D and its JS port. http://box2d-js.sourceforge.net It seems to be quite old port, made in 2008. Is it lacking many features of current Box2D or does it have major issues with it? And are there any alternatives for it?

    Read the article

  • XNA RTS A* pathfinding issues

    - by Slayter
    I'm starting to develop an RTS game using the XNA framework in C# and am still in the very early prototyping stage. I'm working on the basics. I've got unit selection down and am currently working on moving multiple units. I've implemented an A* pathfinding algorithm which works fine for moving a single unit. However when moving multiple units they stack on top of each other. I tried fixing this with a variation of the boids flocking algorithm but this has caused units to sometimes freeze and get stuck trying to move but going no where. Ill post the related methods for moving the units below but ill only post a link to the pathfinding class because its really long and i don't want to clutter up the page. These parts of the code are in the update method for the main controlling class: if (selectedUnits.Count > 0) { int indexOfLeader = 0; for (int i = 0; i < selectedUnits.Count; i++) { if (i == 0) { indexOfLeader = 0; } else { if (Vector2.Distance(selectedUnits[i].position, destination) < Vector2.Distance(selectedUnits[indexOfLeader].position, destination)) indexOfLeader = i; } selectedUnits[i].leader = false; } selectedUnits[indexOfLeader].leader = true; foreach (Unit unit in selectedUnits) unit.FindPath(destination); } foreach (Unit unit in units) { unit.Update(gameTime, selectedUnits); } These three methods control movement in the Unit class: public void FindPath(Vector2 destination) { if (path != null) path.Clear(); Point startPoint = new Point((int)position.X / 32, (int)position.Y / 32); Point endPoint = new Point((int)destination.X / 32, (int)destination.Y / 32); path = pathfinder.FindPath(startPoint, endPoint); pointCounter = 0; if (path != null) nextPoint = path[pointCounter]; dX = 0.0f; dY = 0.0f; stop = false; } private void Move(List<Unit> units) { if (nextPoint == position && !stop) { pointCounter++; if (pointCounter <= path.Count - 1) { nextPoint = path[pointCounter]; if (nextPoint == position) stop = true; } else if (pointCounter >= path.Count) { path.Clear(); pointCounter = 0; stop = true; } } else { if (!stop) { map.occupiedPoints.Remove(this); Flock(units); // Move in X ********* TOOK OUT SPEED ********** if ((int)nextPoint.X > (int)position.X) { position.X += dX; } else if ((int)nextPoint.X < (int)position.X) { position.X -= dX; } // Move in Y if ((int)nextPoint.Y > (int)position.Y) { position.Y += dY; } else if ((int)nextPoint.Y < (int)position.Y) { position.Y -= dY; } if (position == nextPoint && pointCounter >= path.Count - 1) stop = true; map.occupiedPoints.Add(this, position); } if (stop) { path.Clear(); pointCounter = 0; } } } private void Flock(List<Unit> units) { float distanceToNextPoint = Vector2.Distance(position, nextPoint); foreach (Unit unit in units) { float distance = Vector2.Distance(position, unit.position); if (unit != this) { if (distance < space && !leader && (nextPoint != position)) { // create space dX += (position.X - unit.position.X) * 0.1f; dY += (position.Y - unit.position.Y) * 0.1f; if (dX > .05f) nextPoint.X = nextPoint.X - dX; else if (dX < -.05f) nextPoint.X = nextPoint.X + dX; if (dY > .05f) nextPoint.Y = nextPoint.Y - dY; else if (dY < -.05f) nextPoint.Y = nextPoint.Y + dY; if ((dX < .05f && dX > -.05f) && (dY < .05f && dY > -.05f)) stop = true; path[pointCounter] = nextPoint; Console.WriteLine("Make Space: " + dX + ", " + dY); } else if (nextPoint != position && !stop) { dX = speed; dY = speed; Console.WriteLine(dX + ", " + dY); } } } } And here's the link to the pathfinder: https://docs.google.com/open?id=0B_Cqt6txUDkddU40QXBMeTR1djA I hope this post wasn't too long. Also please excuse the messiness of the code. As I said before this is early prototyping. Any help would be appreciated. Thanks!

    Read the article

  • Pathfinding results in false path costs that are too high

    - by user2144536
    I'm trying to implement pathfinding in a game I'm programming using this method. I'm implementing it with recursion but some of the values after the immediate circle of tiles around the player are way off. For some reason I cannot find the problem with it. This is a screen cap of the problem: The pathfinding values are displayed in the center of every tile. Clipped blocks are displayed with the value of 'c' because the values were too high and were covering up the next value. The red circle is the first value that is incorrect. The code below is the recursive method. //tileX is the coordinates of the current tile, val is the current pathfinding value, used[][] is a boolean //array to keep track of which tiles' values have already been assigned public void pathFind(int tileX, int tileY, int val, boolean[][] used) { //increment pathfinding value int curVal = val + 1; //set current tile to true if it hasn't been already used[tileX][tileY] = true; //booleans to know which tiles the recursive call needs to be used on boolean topLeftUsed = false, topUsed = false, topRightUsed = false, leftUsed = false, rightUsed = false, botomLeftUsed = false, botomUsed = false, botomRightUsed = false; //set value of top left tile if necessary if(tileX - 1 >= 0 && tileY - 1 >= 0) { //isClipped(int x, int y) returns true if the coordinates givin are in a tile that can't be walked through (IE walls) //occupied[][] is an array that keeps track of which tiles have an enemy in them // //if the tile is not clipped and not occupied set the pathfinding value if(isClipped((tileX - 1) * 50 + 25, (tileY - 1) * 50 + 25) == false && occupied[tileX - 1][tileY - 1] == false && !(used[tileX - 1][tileY - 1])) { pathFindingValues[tileX - 1][tileY - 1] = curVal; topLeftUsed = true; used[tileX - 1][tileY - 1] = true; } //if it is occupied set it to an arbitrary high number so enemies find alternate routes if the best is clogged if(occupied[tileX - 1][tileY - 1] == true) pathFindingValues[tileX - 1][tileY - 1] = 1000000000; //if it is clipped set it to an arbitrary higher number so enemies don't travel through walls if(isClipped((tileX - 1) * 50 + 25, (tileY - 1) * 50 + 25) == true) pathFindingValues[tileX - 1][tileY - 1] = 2000000000; } //top middle if(tileY - 1 >= 0 ) { if(isClipped(tileX * 50 + 25, (tileY - 1) * 50 + 25) == false && occupied[tileX][tileY - 1] == false && !(used[tileX][tileY - 1])) { pathFindingValues[tileX][tileY - 1] = curVal; topUsed = true; used[tileX][tileY - 1] = true; } if(occupied[tileX][tileY - 1] == true) pathFindingValues[tileX][tileY - 1] = 1000000000; if(isClipped(tileX * 50 + 25, (tileY - 1) * 50 + 25) == true) pathFindingValues[tileX][tileY - 1] = 2000000000; } //top right if(tileX + 1 <= used.length && tileY - 1 >= 0) { if(isClipped((tileX + 1) * 50 + 25, (tileY - 1) * 50 + 25) == false && occupied[tileX + 1][tileY - 1] == false && !(used[tileX + 1][tileY - 1])) { pathFindingValues[tileX + 1][tileY - 1] = curVal; topRightUsed = true; used[tileX + 1][tileY - 1] = true; } if(occupied[tileX + 1][tileY - 1] == true) pathFindingValues[tileX + 1][tileY - 1] = 1000000000; if(isClipped((tileX + 1) * 50 + 25, (tileY - 1) * 50 + 25) == true) pathFindingValues[tileX + 1][tileY - 1] = 2000000000; } //left if(tileX - 1 >= 0) { if(isClipped((tileX - 1) * 50 + 25, (tileY) * 50 + 25) == false && occupied[tileX - 1][tileY] == false && !(used[tileX - 1][tileY])) { pathFindingValues[tileX - 1][tileY] = curVal; leftUsed = true; used[tileX - 1][tileY] = true; } if(occupied[tileX - 1][tileY] == true) pathFindingValues[tileX - 1][tileY] = 1000000000; if(isClipped((tileX - 1) * 50 + 25, (tileY) * 50 + 25) == true) pathFindingValues[tileX - 1][tileY] = 2000000000; } //right if(tileX + 1 <= used.length) { if(isClipped((tileX + 1) * 50 + 25, (tileY) * 50 + 25) == false && occupied[tileX + 1][tileY] == false && !(used[tileX + 1][tileY])) { pathFindingValues[tileX + 1][tileY] = curVal; rightUsed = true; used[tileX + 1][tileY] = true; } if(occupied[tileX + 1][tileY] == true) pathFindingValues[tileX + 1][tileY] = 1000000000; if(isClipped((tileX + 1) * 50 + 25, (tileY) * 50 + 25) == true) pathFindingValues[tileX + 1][tileY] = 2000000000; } //botom left if(tileX - 1 >= 0 && tileY + 1 <= used[0].length) { if(isClipped((tileX - 1) * 50 + 25, (tileY + 1) * 50 + 25) == false && occupied[tileX - 1][tileY + 1] == false && !(used[tileX - 1][tileY + 1])) { pathFindingValues[tileX - 1][tileY + 1] = curVal; botomLeftUsed = true; used[tileX - 1][tileY + 1] = true; } if(occupied[tileX - 1][tileY + 1] == true) pathFindingValues[tileX - 1][tileY + 1] = 1000000000; if(isClipped((tileX - 1) * 50 + 25, (tileY + 1) * 50 + 25) == true) pathFindingValues[tileX - 1][tileY + 1] = 2000000000; } //botom middle if(tileY + 1 <= used[0].length) { if(isClipped((tileX) * 50 + 25, (tileY + 1) * 50 + 25) == false && occupied[tileX][tileY + 1] == false && !(used[tileX][tileY + 1])) { pathFindingValues[tileX][tileY + 1] = curVal; botomUsed = true; used[tileX][tileY + 1] = true; } if(occupied[tileX][tileY + 1] == true) pathFindingValues[tileX][tileY + 1] = 1000000000; if(isClipped((tileX) * 50 + 25, (tileY + 1) * 50 + 25) == true) pathFindingValues[tileX][tileY + 1] = 2000000000; } //botom right if(tileX + 1 <= used.length && tileY + 1 <= used[0].length) { if(isClipped((tileX + 1) * 50 + 25, (tileY + 1) * 50 + 25) == false && occupied[tileX + 1][tileY + 1] == false && !(used[tileX + 1][tileY + 1])) { pathFindingValues[tileX + 1][tileY + 1] = curVal; botomRightUsed = true; used[tileX + 1][tileY + 1] = true; } if(occupied[tileX + 1][tileY + 1] == true) pathFindingValues[tileX + 1][tileY + 1] = 1000000000; if(isClipped((tileX + 1) * 50 + 25, (tileY + 1) * 50 + 25) == true) pathFindingValues[tileX + 1][tileY + 1] = 2000000000; } //call the method on the tiles that need it if(tileX - 1 >= 0 && tileY - 1 >= 0 && topLeftUsed) pathFind(tileX - 1, tileY - 1, curVal, used); if(tileY - 1 >= 0 && topUsed) pathFind(tileX , tileY - 1, curVal, used); if(tileX + 1 <= used.length && tileY - 1 >= 0 && topRightUsed) pathFind(tileX + 1, tileY - 1, curVal, used); if(tileX - 1 >= 0 && leftUsed) pathFind(tileX - 1, tileY, curVal, used); if(tileX + 1 <= used.length && rightUsed) pathFind(tileX + 1, tileY, curVal, used); if(tileX - 1 >= 0 && tileY + 1 <= used[0].length && botomLeftUsed) pathFind(tileX - 1, tileY + 1, curVal, used); if(tileY + 1 <= used[0].length && botomUsed) pathFind(tileX, tileY + 1, curVal, used); if(tileX + 1 <= used.length && tileY + 1 <= used[0].length && botomRightUsed) pathFind(tileX + 1, tileY + 1, curVal, used); }

    Read the article

  • Picture rendered from above and below using an Orthographic camera do not match

    - by Roy T.
    I'm using an orthographic camera to render slices of a model (in order to voxelize it). I render each slice both from above and below in order to determine what is inside each slice. I am using an orthographic camera The model I render is a simple 'T' shape constructed from two cubes. The cubes have the same dimensions and have the same Y (height) coordinate. See figure 1 for a render of it in Blender. I render this model once directly from above and once directly from below. My expectation was that I would get exactly the same image (except for mirroring over the y-axis). However when I render using a very low resolution render target (25x25) the position (in pixels) of the 'T' is different when rendered from above as opposed to rendered from below. See figure 2 and 3. The pink blocks are not part of the original rendering but I've added them so you can easily count/see the differences. Figure 2: the T rendered from above Figure 3: the T rendered from below This is probably due to what I've read about pixel and texel coordinates which might be biased to the top-left as seen from the camera. Since I'm using the same 'up' vector for both of my camera's my bias only shows on the x-axis. I've tried to change the position of the camera and it's look-at by, what I thought, should be half a pixel. I've tried both shifting a single camera and shifting both cameras and while I see some effect I am not able to get a pixel-by-pixel perfect copy from both camera's. Here I initialize the camera and compute, what I believe to be, half pixel. boundsDimX and boundsDimZ is a slightly enlarged bounding box around the model which I also use as the width and height of the view volume of the orthographic camera. Matrix projection = Matrix.CreateOrthographic(boundsDimX, boundsDimZ, 0.5f, sliceHeight + 0.5f); Vector3 halfPixel = new Vector3(boundsDimX / (float)renderTarget.Width, 0, boundsDimY / (float)renderTarget.Height) * 0.5f; This is the code where I set the camera position and camera look ats // Position camera if (downwards) { float cameraHeight = bounds.Max.Y + 0.501f - (sliceHeight * i); Vector3 cameraPosition = new Vector3 ( boundsCentre.X, // possibly adjust by half a pixel? cameraHeight, boundsCentre.Z ); camera.Position = cameraPosition; camera.LookAt = new Vector3(cameraPosition.X, cameraHeight - 1.0f, cameraPosition.Z); } else { float cameraHeight = bounds.Max.Y - 0.501f - (sliceHeight * i); Vector3 cameraPosition = new Vector3 ( boundsCentre.X, cameraHeight, boundsCentre.Z ); camera.Position = cameraPosition; camera.LookAt = new Vector3(cameraPosition.X, cameraHeight + 1.0f, cameraPosition.Z); } Main Question Now you've seen all the problems and code you can guess it. My main question is. How do I align both camera's so that they each render exactly the same image (mirrored along the Y axis)? Figure 1 the original model rendered in blender

    Read the article

  • Undefined fireball movement behavior

    - by optimisez
    Demonstration video I try to do after the player shoot 10 times of fireball, then delete all the fireball objects and recreate a 10 new set of fireball objects. I did it but there is a weird bug happens that sometimes the fireball will come out from top and move to the right after shooting a few times. All the 10 fireballs should follow the player all the time and all the fireball should come out from player even after a new set of fireballs is recreated. Any ideas to fix it? Variables typedef struct gameObject{ float X; float Y; int length; int height; bool action; }; // Fireball #define FIREBALL_NUM 10 LPDIRECT3DTEXTURE9 fireball = NULL; RECT fireballRect; gameObject *fireballDest = new gameObject[FIREBALL_NUM]; int iFireBallAnimation; int fireballCount = 0; Set up Fireball void setUpFireBall() { // Initialize destination rectangle, rectangle height and length for (int i = 0; i < FIREBALL_NUM; i++) { fireballDest[i].X = 0; fireballDest[i].Y = 0; fireballDest[i].length = fireballRect.right - fireballRect.left; fireballDest[i].height = fireballRect.bottom - fireballRect.top; } iFireBallAnimation = fireballRect.right - fireballRect.left; // Initialize boolean for (int i = 0; i < FIREBALL_NUM; i++) { fireballDest[i].action = false; } } Initialize fireball void initFireball() { hr = D3DXCreateTextureFromFileEx(d3dDevice, "fireball.png", 512, 512, D3DX_DEFAULT, NULL, D3DFMT_A8R8G8B8, D3DPOOL_MANAGED, D3DX_DEFAULT, D3DX_DEFAULT, D3DCOLOR_XRGB(255, 255, 0), NULL, NULL, &fireball); // Initialize source rectangle fireballRect.left = 0; fireballRect.top = 256; fireballRect.right = 64; fireballRect.bottom = 320; setUpFireBall(); } Update fireball void update() { updateAnimation(); updateAI(); updatePhysics(); updateGameState(); } void updatePhysics() { motion(); collison(); } void motion() { playerMove(); playerJump(); playerGravity(); shootFireball(); fireballFollowPlayer(); } void shootFireball() { if (keyArr['Z']) fireballDest[fireballCount].action = true; if (fireballDest[fireballCount].action) { fireballDest[fireballCount].X += 10; if (fireballDest[fireballCount].X > 800) fireballCount++; } } void fireballFollowPlayer() { for (int i = 0; i < FIREBALL_NUM; i++) { if (fireballDest[i].action == false) { fireballDest[i].X = playerDest.X - 30; fireballDest[i].Y = playerDest.Y - 14; } } } void updateGameState() { // When no more fireball left, rearm fireball if (fireballCount == FIREBALL_NUM) { delete[] fireballDest; fireballDest = new gameObject[10]; fireballCount = 0; setUpFireBall(); } } Render fireball void renderFireball() { for (int i = 0; i < FIREBALL_NUM; i++) { if (fireballDest[i].action) sprite->Draw(fireball, &fireballRect, NULL, &D3DXVECTOR3(fireballDest[i].X, fireballDest[i].Y, 0), D3DCOLOR_XRGB(255,255, 255)); } }

    Read the article

  • 2D platformers: why make the physics dependent on the framerate?

    - by Archagon
    "Super Meat Boy" is a difficult platformer that recently came out for PC, requiring exceptional control and pixel-perfect jumping. The physics code in the game is dependent on the framerate, which is locked to 60fps; this means that if your computer can't run the game at full speed, the physics will go insane, causing (among other things) your character to run slower and fall through the ground. Furthermore, if vsync is off, the game runs extremely fast. Could those experienced with 2D game programming help explain why the game was coded this way? Wouldn't a physics loop running at a constant rate be a better solution? (Actually, I think a physics loop is used for parts of the game, since some of the entities continue to move normally regardless of the framerate. Your character, on the other hand, runs exactly [fps/60] as fast.) What bothers me about this implementation is the loss of abstraction between the game engine and the graphics rendering, which depends on system-specific things like the monitor, graphics card, and CPU. If, for whatever reason, your computer can't handle vsync, or can't run the game at exactly 60fps, it'll break spectacularly. Why should the rendering step in any way influence the physics calculations? (Most games nowadays would either slow down the game or skip frames.) On the other hand, I understand that old-school platformers on the NES and SNES depended on a fixed framerate for much of their control and physics. Why is this, and would it be possible to create a patformer in that vein without having the framerate dependency? Is there necessarily a loss of precision if you separate the graphics rendering from the rest of the engine? Thank you, and sorry if the question was confusing.

    Read the article

  • How do I do Collisions in my JavaScript Game Code Below?

    - by Henry
    I'm trying to figure out how would I add collision detection to my code so that when the "Man" character touches the "RedHouse" the RedHouse disappears? Thanks. By the way, I'm new to how things are done on this site, so thus, if there is anything else needed or so, let me know. <title>HMan</title> <body style="background:#808080;"> <br> <canvas id="canvasBg" width="800px" height="500px"style="display:block;background:#ffffff;margin:100px auto 0px;"></canvas> <canvas id="canvasRedHouse" width="800px" height="500px" style="display:block;margin:-500px auto 0px;"></canvas> <canvas id="canvasEnemy" width="800px" height="500px" style="display:block;margin:-500px auto 0px;"></canvas> <canvas id="canvasEnemy2" width="800px" height="500px" style="display:block;margin:-500px auto 0px;"></canvas> <canvas id="canvasMan" width="800px" height="500px" style="display:block;margin:-500px auto 0px;"></canvas> <script> var isPlaying = false; var requestAnimframe = window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.msRequestAnimationFrame || window.oRequestAnimationFrame; var canvasBg = document.getElementById('canvasBg'); var ctxBg = canvasBg.getContext('2d'); var canvasRedHouse = document.getElementById('canvasRedHouse'); var ctxRedHouse = canvasRedHouse.getContext('2d'); var House1; House1 = new RedHouse(); var canvasMan = document.getElementById('canvasMan'); var ctxMan = canvasMan.getContext('2d'); var Man1; Man1 = new Man(); var imgSprite = new Image(); imgSprite.src = 'SpritesI.png'; imgSprite.addEventListener('load',init,false); function init() { drawBg(); startLoop(); document.addEventListener('keydown',checkKeyDown,false); document.addEventListener('keyup',checkKeyUp,false); } function drawBg() { var SpriteSourceX = 0; var SpriteSourceY = 0; var drawManOnScreenX = 0; var drawManOnScreenY = 0; ctxBg.drawImage(imgSprite,SpriteSourceX,SpriteSourceY,800,500,drawManOnScreenX, drawManOnScreenY,800,500); } function clearctxBg() { ctxBg.clearRect(0,0,800,500); } function Man() { this.SpriteSourceX = 10; this.SpriteSourceY = 540; this.width = 40; this.height = 115; this.DrawManOnScreenX = 100; this.DrawManOnScreenY = 260; this.speed = 10; this.actualFrame = 1; this.speed = 2; this.isUpKey = false; this.isRightKey = false; this.isDownKey = false; this.isLeftKey = false; } Man.prototype.draw = function () { clearCtxMan(); this.updateCoors(); this.checkDirection(); ctxMan.drawImage(imgSprite,this.SpriteSourceX,this.SpriteSourceY+this.height* this.actualFrame, this.width,this.height,this.DrawManOnScreenX,this.DrawManOnScreenY, this.width,this.height); } Man.prototype.updateCoors = function(){ this.leftX = this.DrawManOnScreenX; this.rightX = this.DrawManOnScreenX + this.width; this.topY = this.DrawManOnScreenY; this.bottomY = this.DrawManOnScreenY + this.height; } Man.prototype.checkDirection = function () { if (this.isUpKey && this.topY > 240) { this.DrawManOnScreenY -= this.speed; } if (this.isRightKey && this.rightX < 800) { this.DrawManOnScreenX += this.speed; } if (this.isDownKey && this.bottomY < 500) { this.DrawManOnScreenY += this.speed; } if (this.isLeftKey && this.leftX > 0) { this.DrawManOnScreenX -= this.speed; } if (this.isRightKey && this.rightX < 800) { if (this.actualFrame > 0) { this.actualFrame = 0; } else { this.actualFrame++; } } if (this.isLeftKey) { if (this.actualFrame > 2) { this.actualFrame = 2; } function checkKeyDown(var keyID = e.keyCode || e.which; if (keyID === 38) { Man1.isUpKey = true; e.preventDefault(); } if (keyID === 39 ) { Man1.isRightKey = true; e.preventDefault(); } if (keyID === 40 ) { Man1.isDownKey = true; e.preventDefault(); } if (keyID === 37 ) { Man1.isLeftKey = true; e.preventDefault(); } } function checkKeyUp(e) { var keyID = e.keyCode || e.which; if (keyID === 38 || keyID === 87) { Man1.isUpKey = false; e.preventDefault(); } if (keyID === 39 || keyID === 68) { Man1.isRightKey = false; e.preventDefault(); } if (keyID === 40 || keyID === 83) { Man1.isDownKey = false; e.preventDefault(); } if (keyID === 37 || keyID === 65) { Man1.isLeftKey = false; e.preventDefault(); } } function clearCtxMan() { ctxMan.clearRect(0,0,800,500); } function RedHouse() { this.srcX = 135; this.srcY = 525; this.width = 265; this.height = 245; this.drawX = 480; this.drawY = 85; } RedHouse.prototype.draw = function () { clearCtxRedHouse(); ctxRedHouse.drawImage(imgSprite,this.srcX,this.srcY, this.width,this.height,this.drawX,this.drawY,this.width,this.height); }; function clearCtxRedHouse() { ctxRedHouse.clearRect(0,0,800,500); } function loop() { if (isPlaying === true){ Man1.draw(); House1.draw(); requestAnimframe(loop); } } function startLoop(){ isPlaying = true; loop(); } function stopLoop(){ isPlaying = false; } </script> <style> .top{ position: absolute; top: 4px; left: 10px; color:black; } .top2{ position: absolute; top: 60px; left: 10px; color:black; } </style> <div class="top"> <p><font face="arial" color="black" size="4"><b>HGame</b><font/><p/> <p><font face="arial" color="black" size="3"> My Game Here <font/><p/> </div> <div class="top2"> <p><font face="arial" color="black" size="3"> It will start now <font/><p/> </div>

    Read the article

  • How can I create and animate 2D skeletons for HTML5 Javascript games? [on hold]

    - by user414209
    I'm trying to make a 2D fighting game in HTML5(somewhat like street fighter). So basically there are two players, one AI and one Human. The players need to have animations for the body movements. Also, there needs to be some collision detection system. I'm using createjs for coding but to design models/objects/animations, I need some other software. So I'm looking for a software that can: easily make custom animation of 2d objects. The objects structure(skeleton etc.) will be same once defined but need to be defined once. Can export the animations and models in a js readable format(preferably json) Collision detection can be done easily after the exported format is loaded in a game engine. For point 1, I'm looking for some generic skeleton based animation. Sprite-sheet based animations will be difficult for collision detection.

    Read the article

  • How can I implement 2D cel shading in XNA?

    - by Artii
    So I was just wondering on how to give a scene I am rendering a hand drawn look (like say Crayon Physics). I don't really want to preprocess the sprites and was thinking of using a shader. Cel shading supplies the effect I want to achieve, but I am only aware of the 3D instances for it. So I wanted to ask if anyone knew a way to get this effect in 2D, or if cel shading would work just as fine on 2D scenes?

    Read the article

  • Structure gameobjects and call events

    - by waco001
    I'm working on a 2D tile based game in which the player interacts with other game objects (chests, AI, Doors, Houses etc...). The entire map will be stored in a file which I can read. When loading the tilemap, it will find any tile with the ID that represents a gameobject and store it in a hashmap (right data structure I think?). private static HashMap<Integer, Class<GameObject>> gameObjects = new HashMap<Integer, Class<GameObject>>(); How exactly would I go about calling, and checking for events? I figure that I would just call the update, render and input methods of each gameobject using the hashmap. Should I got towards a Minecraft/Bukkit approach (sorry only example I can think of), where the user registers an event, and it gets called whenever that event happens, and where should I go as in resources to learn about that type of programming, (Java, LWJGL). Or should I just loop through the entire hashmap looking for an event that fits? Thanks waco

    Read the article

  • How does interpolation actually work to smooth out an object's movement?

    - by user22241
    I've asked a few similar questions over the past 8 months or so with no real joy, so I am going make the question more general. I have an Android game which is OpenGL ES 2.0. within it I have the following Game Loop: My loop works on a fixed time step principle (dt = 1 / ticksPerSecond) loops=0; while(System.currentTimeMillis() > nextGameTick && loops < maxFrameskip){ updateLogic(dt); nextGameTick+=skipTicks; timeCorrection += (1000d/ticksPerSecond) % 1; nextGameTick+=timeCorrection; timeCorrection %=1; loops++; } render(); My intergration works like this: sprite.posX+=sprite.xVel*dt; sprite.posXDrawAt=sprite.posX*width; Now, everything works pretty much as I would like. I can specify that I would like an object to move across a certain distance (screen width say) in 2.5 seconds and it will do just that. Also because of the frame skipping that I allow in my game loop, I can do this on pretty much any device and it will always take 2.5 seconds. Problem However, the problem is that when a render frame skips, the graphic stutter. It's extremely annoying. If I remove the ability to skip frames, then everything is smooth as you like, but will run at different speeds on different devices. So it's not an option. I'm still not sure why the frame skips, but I would like to point out that this is Nothing to do with poor performance, I've taken the code right back to 1 tiny sprite and no logic (apart from the logic required to move the sprite) and I still get skipped frames. And this is on a Google Nexus 10 tablet (and as mentioned above, I need frame skipping to keep the speed consistent across devices anyway). So, the only other option I have is to use interpolation (or extrapolation), I've read every article there is out there but none have really helped me to understand how it works and all of my attempted implementations have failed. Using one method I was able to get things moving smoothly but it was unworkable because it messed up my collision. I can foresee the same issue with any similar method because the interpolation is passed to (and acted upon within) the rendering method - at render time. So if Collision corrects position (character now standing right next to wall), then the renderer can alter it's position and draw it in the wall. So I'm really confused. People have said that you should never alter an object's position from within the rendering method, but all of the examples online show this. So I'm asking for a push in the right direction, please do not link to the popular game loop articles (deWitters, Fix your timestep, etc) as I've read these multiple times. I'm not asking anyone to write my code for me. Just explain please in simple terms how Interpolation actually works with some examples. I will then go and try to integrate any ideas into my code and will ask more specific questions if need-be further down the line. (I'm sure this is a problem many people struggle with).

    Read the article

  • Physics System ignores collision in some rare cases

    - by Gajoo
    I've been developing a simple physics engine for my game. since the game physics is very simple I've decided to increase accuracy a little bit. Instead of formal integration methods like fourier or RK4, I'm directly computing the results after delta time "dt". based on the very first laws of physics : dx = 0.5 * a * dt^2 + v0 * dt dv = a * dt where a is acceleration and v0 is object's previous velocity. Also to handle collisions I've used a method which is somehow different from those I've seen so far. I'm detecting all the collision in the given time frame, stepping the world forward to the nearest collision, resolving it and again check for possible collisions. As I said the world consist of very simple objects, so I'm not loosing any performance due to multiple collision checking. First I'm checking if the ball collides with any walls around it (which is working perfectly) and then I'm checking if it collides with the edges of the walls (yellow points in the picture). the algorithm seems to work without any problem except some rare cases, in which the collision with points are ignored. I've tested everything and all the variables seem to be what they should but after leaving the system work for a minute or two the system the ball passes through one of those points. Here is collision portion of my code, hopefully one of you guys can give me a hint where to look for a potential bug! void PhysicalWorld::checkForPointCollision(Vec2 acceleration, PhysicsComponent& ball, Vec2& collisionNormal, float& collisionTime, Vec2 target) { // this function checks if there will be any collision between a circle and a point // ball contains informations about the circle (it's current velocity, position and radius) // collisionNormal is an output variable // collisionTime is also an output varialbe // target is the point I want to check for collisions Vec2 V = ball.mVelocity; Vec2 A = acceleration; Vec2 P = ball.mPosition - target; float wallWidth = mMap->getWallWidth() / (mMap->getWallWidth() + mMap->getHallWidth()) / 2; float r = ball.mRadius / (mMap->getWallWidth() + mMap->getHallWidth()); // r is ball radius scaled to match actual rendered object. if (A.any()) // todo : I need to first correctly solve the collisions in case there is no acceleration return; if (V.any()) // if object is not moving there will be no collisions! { float D = P.x * V.y - P.y * V.x; float Delta = r*r*V.length2() - D*D; if(Delta < eps) return; Delta = sqrt(Delta); float sgnvy = V.y > 0 ? 1: (V.y < 0?-1:0); Vec2 c1(( D*V.y+sgnvy*V.x*Delta) / V.length2(), (-D*V.x+fabs(V.y)*Delta) / V.length2()); Vec2 c2(( D*V.y-sgnvy*V.x*Delta) / V.length2(), (-D*V.x-fabs(V.y)*Delta) / V.length2()); float t1 = (c1.x - P.x) / V.x; float t2 = (c2.x - P.x) / V.x; if(t1 > eps && t1 <= collisionTime) { collisionTime = t1; collisionNormal = c1; } if(t2 > eps && t2 <= collisionTime) { collisionTime = t2; collisionNormal = c2; } } } // this function should step the world forward by dt. it doesn't check for collision of any two balls (components) // it just checks if there is a collision between the current component and 4 points forming a rectangle around it. void PhysicalWorld::step(float dt) { for (unsigned i=0;i<mObjects.size();i++) { PhysicsComponent &current = *mObjects[i]; Vec2 acceleration = current.mForces * current.mInvMass; float rt=dt; // stores how much more the world should advance while(rt > eps) { float collisionTime = rt; Vec2 collisionNormal = Vec2(0,0); float halfWallWidth = mMap->getWallWidth() / (mMap->getWallWidth() + mMap->getHallWidth()) / 2; // we check if there is any collision with any of those 4 points around the ball // if there is a collision both collisionNormal and collisionTime variables will change // after these functions collisionTime will be exactly the value of nearest collision (if any) // and if there was, collisionNormal will report in which direction the ball should return. checkForPointCollision(acceleration,current,collisionNormal,collisionTime,Vec2(floor(current.mPosition.x) + halfWallWidth,floor(current.mPosition.y) + halfWallWidth)); checkForPointCollision(acceleration,current,collisionNormal,collisionTime,Vec2(floor(current.mPosition.x) + halfWallWidth, ceil(current.mPosition.y) - halfWallWidth)); checkForPointCollision(acceleration,current,collisionNormal,collisionTime,Vec2( ceil(current.mPosition.x) - halfWallWidth,floor(current.mPosition.y) + halfWallWidth)); checkForPointCollision(acceleration,current,collisionNormal,collisionTime,Vec2( ceil(current.mPosition.x) - halfWallWidth, ceil(current.mPosition.y) - halfWallWidth)); // either if there is a collision or if there is not we step the forward since we are sure there will be no collision before collisionTime current.mPosition += collisionTime * (collisionTime * acceleration * 0.5 + current.mVelocity); current.mVelocity += collisionTime * acceleration; // if the ball collided with anything collisionNormal should be at least none zero in one of it's axis if (collisionNormal.any()) { collisionNormal *= Dot(collisionNormal, current.mVelocity) / collisionNormal.length2(); current.mVelocity -= 2 * collisionNormal; // simply reverse velocity along collision normal direction } rt -= collisionTime; } // reset all forces for current object so it'll be ready for later game event current.mForces.zero(); } }

    Read the article

< Previous Page | 403 404 405 406 407 408 409 410 411 412 413 414  | Next Page >