Search Results

Search found 37616 results on 1505 pages for 'model driven development'.

Page 549/1505 | < Previous Page | 545 546 547 548 549 550 551 552 553 554 555 556 | Next Page >

Coarse Collision Detection in highly dynamic environment

- by Millianz

I'm currently working a 3D space game with A LOT of dynamic objects that are all moving (there is pretty much no static environment). I have the collision detection and resolution working just fine, but I am now trying to optimize the collision detection (which is currently O(N^2) -- linear search). I thought about multiple options, a bounding volume hierarchy, a Binary Spatial Partitioning tree, an Octree or a Grid. I however need some help with deciding what's best for my situation. A grid seems unfeasible simply due to the space requirements and cache coherence problems. Since everything is so dynamic however, it seems to be that trees aren't ideal either, since they would have to be completely rebuilt every frame. I must admit I never implemented a physics engine that required spatial partitioning, do I indeed need to rebuild the tree every frame (assuming that everything is constantly moving) or can I update the trees after integrating? Advice is much appreciated - to give some more background: You're flying a space ship in an asteroid field, and there are lots and lots of asteroids and some enemy ships, all of which shoot bullets. EDIT: I came across the "Sweep an Prune" algorithm, which seems like the right thing for my purposes. It appears like the right mixture of fast building of the data structures involved and detailed enough partitioning. This is the best resource I can find: http://www.codercorner.com/SAP.pdf If anyone has any suggestions whether or not I'm going in the right direction, please let me know.

Read the article
Jumping with Mecanim synchronization

- by Abhishek Deb

I am using Unity3D 4.1 for one of my projects. I have a robot character which is always running. I am using mecanim animation system. What I really want:When I press Space bar, the character should jump up in the air, triggering an animation clip and then by the time it reaches the ground, the animation clip should also end. What actually is happening:When I press Space bar, the character jumps in the air. Animation clip plays as it should, but ends way before it reaches the ground. So, it looks like he is running in the mid air. What have I done: I have this humanoid robot setup with a jump animation bounded with the space bar key. Also, instead of using root motion, I am directly moving the robot from code. //Jumping if(Input.GetKeyDown(KeyCode.Space)){ rigidbody.AddForce(Vector3.up*jumpVelocty); anim.SetBool("Jump",true); } else anim.SetBool("Jump",false); Character's Details: Rigidbody = Mass:30, Freeze rotaion:x,y,z Capsule Collider = Material: metal, center(0,4.5,0), radius:1, height:11 Script = jumpVelocity:20000 Jump Animation Clip: ~ 2 seconds. I am really out of ideas how to synchronize everything. Should I make the character jump in some other way so that it quickly comes down and touches the ground to match the animation clip? If yes, please provide a direction.

Read the article
How can I calculate a vertex normal for a hard edge?

- by K.G.

Here is a picture of a lovely polygon: Circled is a vertex, and numbered are its adjacent faces. I have calculated the normals of those faces as such (not yet normalized, 0-indexed): Vertex 1 normal 0: 0.000000 0.000000 -0.250000 Vertex 1 normal 1: 0.000000 0.000000 -0.250000 Vertex 1 normal 2: -0.250000 0.000000 0.000000 Vertex 1 normal 3: -0.250000 0.000000 0.000000 Vertex 1 normal 4: 0.250000 0.000000 0.000000 What I'm wondering is, how can I determine, taken as given that I want this vertex to represent a hard edge, whether its normal should be the normal of 1/2 or 3/4? My plan after I glanced at the sketch I used to put this together was "Ha! I'll just use whichever two faces have the same normal!" and now I see that there are two sets of two faces for which this is true. Is there a rule I can apply based on the face winding, angle of the adjacent edges, moon phase, coin flip, to consistently choose a normal direction for this box? For the record, all of the other polygons I plan to use will have their normals dictated in Maya, but after encountering this problem, it made me really curious.

Read the article
Ruby: implementing alpha-beta pruning for tic-tac-toe

- by DerNalia

So, alpha-beta pruning seems to be the most efficient algorithm out there aside from hard coding (for tic tac toe). However, I'm having problems converting the algorithm from the C++ example given in the link: http://www.webkinesia.com/games/gametree.php #based off http://www.webkinesia.com/games/gametree.php # (converted from C++ code from the alpha - beta pruning section) # returns 0 if draw LOSS = -1 DRAW = 0 WIN = 1 @next_move = 0 def calculate_ai_next_move score = self.get_best_move(COMPUTER, WIN, LOSS) return @next_move end def get_best_move(player, alpha, beta) best_score = nil score = nil if not self.has_available_moves? return false elsif self.has_this_player_won?(player) return WIN elsif self.has_this_player_won?(1 - player) return LOSS else best_score = alpha NUM_SQUARES.times do |square| if best_score >= beta break end if self.state[square].nil? self.make_move_with_index(square, player) # set to negative of opponent's best move; we only need the returned score; # the returned move is irrelevant. score = -get_best_move(1-player, -beta, -alpha) if (score > bestScore) @next_move = square best_score = score end undo_move(square) end end end return best_score end the problem is that this is returning nil. some support methods that are used above: WAYS_TO_WIN = [[0, 1, 2], [3, 4, 5], [6, 7, 8], [0, 3, 6], [1, 4, 7], [2, 5, 8],[0, 4, 8], [2, 4, 6]] def has_this_player_won?(player) result = false WAYS_TO_WIN.each {|solution| result = self.state[solution[0]] if contains_win?(solution) } return (result == player) end def contains_win?(ttt_win_state) ttt_win_state.each do |pos| return false if self.state[pos] != self.state[ttt_win_state[0]] or self.state[pos].nil? end return true end def make_move(x, y, player) self.set_square(x,y, player) end

Read the article
GoogleAppEngine : ClassNotFoundException : javax.jdo.metadata.ComponentMetadata

- by James.Elsey

I'm trying to deploy my application to a locally running GoogleAppEngine development server, but I'm getting the following stack trace when I start the server Apr 23, 2010 9:03:33 PM com.google.apphosting.utils.jetty.JettyLogger warn WARNING: Nested in org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'clientDao' defined in ServletContext resource [/WEB-INF/applicationContext.xml]: Cannot resolve reference to bean 'entityManagerFactory' while setting bean property 'entityManagerFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in ServletContext resource [/WEB-INF/applicationContext.xml]: Invocation of init method failed; nested exception is java.lang.NoClassDefFoundError: javax/jdo/metadata/ComponentMetadata: java.lang.ClassNotFoundException: javax.jdo.metadata.ComponentMetadata at java.net.URLClassLoader$1.run(URLClassLoader.java:217) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:205) at java.lang.ClassLoader.loadClass(ClassLoader.java:319) at com.google.appengine.tools.development.IsolatedAppClassLoader.loadClass(IsolatedAppClassLoader.java:151) at java.lang.ClassLoader.loadClass(ClassLoader.java:264) at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:332) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:264) at javax.jdo.JDOHelper$18.run(JDOHelper.java:2009) at javax.jdo.JDOHelper$18.run(JDOHelper.java:2007) at java.security.AccessController.doPrivileged(Native Method) at javax.jdo.JDOHelper.forName(JDOHelper.java:2006) at javax.jdo.JDOHelper.invokeGetPersistenceManagerFactoryOnImplementation(JDOHelper.java:1155) at javax.jdo.JDOHelper.getPersistenceManagerFactory(JDOHelper.java:803) at javax.jdo.JDOHelper.getPersistenceManagerFactory(JDOHelper.java:698) at org.datanucleus.jpa.EntityManagerFactoryImpl.initialisePMF(EntityManagerFactoryImpl.java:482) at org.datanucleus.jpa.EntityManagerFactoryImpl.<init>(EntityManagerFactoryImpl.java:255) at org.datanucleus.store.appengine.jpa.DatastoreEntityManagerFactory.<init>(DatastoreEntityManagerFactory.java:68) at org.datanucleus.store.appengine.jpa.DatastorePersistenceProvider.createContainerEntityManagerFactory(DatastorePersistenceProvider.java:45) at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:224) at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:291) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1369) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1335) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:473) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory$1.run(AbstractAutowireCapableBeanFactory.java:409) at java.security.AccessController.doPrivileged(Native Method) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:380) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:264) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:261) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:269) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:104) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1245) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1010) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:472) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory$1.run(AbstractAutowireCapableBeanFactory.java:409) at java.security.AccessController.doPrivileged(Native Method) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:380) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:264) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:261) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:429) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:728) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:380) at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:255) at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:199) at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:45) at org.mortbay.jetty.handler.ContextHandler.startContext(ContextHandler.java:530) at org.mortbay.jetty.servlet.Context.startContext(Context.java:135) at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1218) at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:500) at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:40) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:117) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:40) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:117) at org.mortbay.jetty.Server.doStart(Server.java:217) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:40) at com.google.appengine.tools.development.JettyContainerService.startContainer(JettyContainerService.java:181) at com.google.appengine.tools.development.AbstractContainerService.startup(AbstractContainerService.java:116) at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerImpl.java:217) at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:162) at com.google.appengine.tools.util.Parser$ParseResult.applyArgs(Parser.java:48) at com.google.appengine.tools.development.DevAppServerMain.<init>(DevAppServerMain.java:113) at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMain.java:89) The server is running at http://localhost:1234/ I'm a little confused over this, since I have the same application running locally on GlassFish/MySQL. All I have done is to swap in the relevant jar files, and change the persistence.xml. My applicationContext.xml looks as follows : <context:annotation-config/> <bean id="clientDao" class="com.jameselsey.salestracker.dao.jpa.JpaDaoClient"> <property name="entityManagerFactory" ref="entityManagerFactory"/> </bean> <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"/> <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager"> <property name="entityManagerFactory" ref="entityManagerFactory" /> </bean> <bean id="org.springframework.context.annotation.internalPersistenceAnnotationProcessor" class="com.jameselsey.salestracker.util.GaeFixInternalPersistenceAnnotationProcessor" /> <bean class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor"/> <tx:annotation-driven/> <bean id="clientService" class="com.jameselsey.salestracker.service.ClientService"/> </beans> My JPA DAO looks like this public class JpaDao extends JpaDaoSupport { protected <T> List<T> findAll(Class<T> clazz) { return getJpaTemplate().find("select c from " + clazz.getName() + " c"); } protected <T> T findOne(String jpql, Map params) { List<T> results = getJpaTemplate().findByNamedParams(jpql, params); if(results.isEmpty()) { return null; } if(results.size() > 1) { throw new IncorrectResultSizeDataAccessException(1, results.size()); } return results.get(0); } } And an example implemented method looks like this : @Override public Client getClientById(Integer clientId) { String jpql = "SELECT c " + "FROM com.jameselsey.salestracker.domain.Client c " + "WHERE c.id = " + clientId; return (Client) getJpaTemplate().find(jpql).get(0); } Like I say, this works ok on Glassfish/MySQL, is it possible this error could be a red herring to something else?

Read the article
Turn-based tile game dynamic item/skill/command script files

- by user1542

I want to create a mechanism that could read text script, for example some kind of custom script such as ".skill" or ".item", which maybe contain some sort of simple script like .item Item.Name = "Strength Gauntlet"; Character.STR += 20; .. .skill Skill.Name = "Poison Attack"; Skill.Description = "Steal HP and inflict poison"; Player.HP += 200; Enemy.HP -= 200; Enemy.Status += Status.POISON; It may be different from this, but just want to give some idea of what I desire. However, I do not know how to dynamically parse these things and translate it into working script. For example, in battle scenerio, I should make my game read one of this ".skill" file and apply it to the current enemy, or the current player. How would I do this? Should I go for String parsing? It is like a script engine, but I prefer C# than creating new language, so how would I parse custom files into appropiate status commands? Another problem is, I have also created a command engine which would read String input and parse it into action such as "MOVE (1,2)" would move character to tile (1,2). Each command belong to separate class, and provide generic parsing method that should be implemented by hand. This is for the reason of custom number/type of arguments per each command. However, I think this is not well designed, because I desire it to automatically parse the parameters according to specify list of types. For example, MOVE command in "MOVE 1 2" would automatically parse the parameters into int, int and put it into X and Y. Now, this form can change, and we should be able to manually specify all type of formats. Any suggestion to this problem? Should I change from string parsing to some hardcode methods/classes?

Read the article
Finding Z given X & Y coordinates on terrain?

- by mrky

I need to know what the most efficient way of finding Z given X & Y coordinates on terrain. My terrain is set up as a grid, each grid block consisting of two triangles, which may be flipped in any direction. I want to move game objects smoothly along the floor of the terrain without "stepping." I'm currently using the following method with unexpected results: double mapClass::getZ(double x, double y) { int vertexIndex = ((floor(y))*width*2)+((floor(x))*2); vec3ray ray = {glm::vec3(x, y, 2), glm::vec3(x, y, 0)}; vec3triangle tri1 = { glmFrom(vertices[vertexIndex].v1), glmFrom(vertices[vertexIndex].v2), glmFrom(vertices[vertexIndex].v3) }; vec3triangle tri2 = { glmFrom(vertices[vertexIndex+1].v1), glmFrom(vertices[vertexIndex+1].v2), glmFrom(vertices[vertexIndex+1].v3) }; glm::vec3 intersect; if (!intersectRayTriangle(tri1, ray, intersect)) { intersectRayTriangle(tri2, ray, intersect); } return intersect.z; } intersectRayTriangle() and glmFrom() are as follows: bool intersectRayTriangle(vec3triangle tri, vec3ray ray, glm::vec3 &worldIntersect) { glm::vec3 barycentricIntersect; if (glm::intersectLineTriangle(ray.origin, ray.direction, tri.p0, tri.p1, tri.p2, barycentricIntersect)) { // Convert barycentric to world coordinates double u, v, w; u = barycentricIntersect.x; v = barycentricIntersect.y; w = 1 - (u+v); worldIntersect.x = (u * tri.p0.x + v * tri.p1.x + w * tri.p2.x); worldIntersect.y = (u * tri.p0.y + v * tri.p1.y + w * tri.p2.y); worldIntersect.z = (u * tri.p0.z + v * tri.p1.z + w * tri.p2.z); return true; } else { return false; } } glm::vec3 glmFrom(s_point3f point) { return glm::vec3(point.x, point.y, point.z); } My convenience structures are defined as: struct s_point3f { GLfloat x, y, z; }; struct s_triangle3f { s_point3f v1, v2, v3; }; struct vec3ray { glm::vec3 origin, direction; }; struct vec3triangle { glm::vec3 p0, p1, p2; }; vertices is defined as: std::vector<s_triangle3f> vertices; Basically, I'm trying to get the intersect of a ray (which is positioned at the x, and y coordinates specified facing pointing downwards toward the terrain) and one of the two triangles on the grid. getZ() rarely returns anything but 0. Other times, the numbers it generates seem to be completely off. Am I taking the wrong approach? Can anyone see a problem with my code? Any help or critique is appreciated!

Read the article
problem adding bumpmap to textured gluSphere in JOGL

- by ChocoMan

I currently have one texture on a gluSphere that represents the Earth being displayed perfectly, but having trouble figuring out how to implement a bumpmap as well. The bumpmap resides in "res/planet/earth/earthbump1k.jpg".Here is the code I have for the regular texture: gl.glTranslatef(xPath, 0, yPath + zPos); gl.glColor3f(1.0f, 1.0f, 1.0f); // base color for earth earthGluSphere = glu.gluNewQuadric(); colorTexture.enable(); // enable texture colorTexture.bind(); // bind texture // draw sphere... glu.gluDeleteQuadric(earthGluSphere); colorTexture.disable(); // texturing public void loadPlanetTexture(GL2 gl) { InputStream colorMap = null; try { colorMap = new FileInputStream("res/planet/earth/earthmap1k.jpg"); TextureData data = TextureIO.newTextureData(colorMap, false, null); colorTexture = TextureIO.newTexture(data); colorTexture.getImageTexCoords(); colorTexture.setTexParameteri(GL2.GL_TEXTURE_MAG_FILTER, GL2.GL_LINEAR); colorTexture.setTexParameteri(GL2.GL_TEXTURE_MIN_FILTER, GL2.GL_NEAREST); colorMap.close(); } catch(IOException e) { e.printStackTrace(); System.exit(1); } // Set material properties gl.glTexParameteri(GL2.GL_TEXTURE_2D, GL2.GL_TEXTURE_MAG_FILTER, GL2.GL_LINEAR); gl.glTexParameteri(GL2.GL_TEXTURE_2D, GL2.GL_TEXTURE_MIN_FILTER, GL2.GL_NEAREST); colorTexture.setTexParameteri(GL2.GL_TEXTURE_2D, GL2.GL_TEXTURE_WRAP_S); colorTexture.setTexParameteri(GL2.GL_TEXTURE_2D, GL2.GL_TEXTURE_WRAP_T); } How would I add the bumpmap as well to the same gluSphere?

Read the article
Scrolling background stops after awhile?

- by Lewis

Can anyone tell me where my maths is wrong please, it stops scrolling after awhile. if (background.position.y < background2.position.y) { background.position = ccp(background.contentSize.width / 2, background.position.y - 50 * delta); background2.position = ccp(background.contentSize.width / 2, background.position.y + background.contentSize.height); } else { background.position = ccp(background2.contentSize.width / 2, background2.position.y - 50 * delta); background.position = ccp(background2.contentSize.width / 2, background2.position.y + background.contentSize.height); } //reset if (background.position.y <-background.contentSize.height / 2) { background.position = ccp(background.contentSize.width / 2 ,background2.position.y + background2.contentSize.height); } else if (background2.position.y < -background2.contentSize.height / 2) { background2.position = ccp(background2.contentSize.width / 2, background.position.y + background.contentSize.height); }

Read the article
Better way to do AI Behavior in AS3/Flixel

- by joon

I'm making a game in Flixel and I need to program an NPC. It's rapidly turning more complex than I expected. I was wondering if there are any best practices, tutorials or examples that you can refer me to, to see how this is done. I can probably hack it together, which is what I always do, but it would be nice if I can make it maintanable and can add stuff later on. Here's screenshot to give you an idea: The butler will be an NPC that will follow you, or guide you, and talk to you the whole time. EDIT: More specifically: What I have now is a long list of IF statements in the update loop of the butler (about 8 different cases), and all I have covered is his walking behavior. I want him to comment on things and sometimes switch his main behavior to be more aggresive or distant,... Is there any way to keep track of this, or is complex code with many many nested if statements the way to go?

Read the article
Component-wise GLSL vector branching

- by Gustavo Maciel

I'm aware that it usually is a BAD idea to operate separately on GLSL vec's components separately. For example: //use instrinsic functions, they do the calculation on 4 components at a time. float dot = v1.x*v2.x + v1.y * v2.y + v1.z * v2.z; //NEVER float dot = dot(v1, v2); //YES //Multiply one by one is not good too, since the ALU can do the 4 components at a time too. vec3 mul = vec3(v1.x * v2.x, v1.y * v2.y, v1.z * v2.z); //NEVER vec3 mul = v1 * v2; I've been struggling thinking, are there equivalent operations for branching? For example: vec4 Overlay(vec4 v1, vec4 v2, vec4 opacity) { bvec4 less = lessThan(v1, vec4(0.5)); vec4 blend; for(int i = 0; i < 4; ++i) { if(less[i]) blend[i] = 2.0 * v1[i]*v2[i]; else blend[i] = 1.0 - 2.0 * (1.0 - v1[i])*(1.0 - v2[i]); } return v1 + (blend-v1)*opacity; } This is a Overlay operator that works component wise. I'm not sure if this is the best way to do it, since I'm afraid these for and if can be a bottleneck later. Tl;dr, Can I branch component wise? If yes, how can I optimize that Overlay function with it?

Read the article
Lighting-Reflectance Models & Licensing Issues

- by codey

Generally, or specifically, is there any licensing issue with using any of the well known lighting/reflectance models (i.e. the BRDFs or other distribution or approximation functions): Phong, Blinn–Phong, Cook–Torrance, Blinn-Torrance-Sparrow, Lambert, Minnaert, Oren–Nayar, Ward, Strauss, Ashikhmin-Shirley and common modifications where applicable, such as: Beckmann distribution, Blinn distribution, Schlick's approximation, etc. in your shader code utilised in a commercial product? Or is it a non-issue?

Read the article
Sounds to describe the weather?

- by Matthew

I'm trying to think of sounds that will help convey the time of day and weather condition. I'm not even sure of all the weather conditions I would consider, and some are obvious. Like if it's raining, the sound of rain. But then I'm thinking, what about for a calm day? If it's morning time, I could do birds chirping or something. Night time could be an owl or something. What are some good combinations of sounds/weather/time to have a good effect?

Read the article
OpenGL Tessellation makes point

- by urza57

A little problem with my tessellation shader. I try to implement a simple tessellation shader but it only makes points. Here's my vertex shader : out vec4 ecPosition; out vec3 ecNormal; void main( void ) { vec4 position = gl_Vertex; gl_Position = gl_ModelViewProjectionMatrix * position; ecPosition = gl_ModelViewMatrix * position; ecNormal = normalize(gl_NormalMatrix * gl_Normal); } My tessellation control shader : layout(vertices = 3) out; out vec4 ecPosition3[]; in vec3 ecNormal[]; in vec4 ecPosition[]; out vec3 myNormal[]; void main() { gl_out[gl_InvocationID].gl_Position = gl_in[gl_InvocationID].gl_Position; myNormal[gl_InvocationID] = ecNormal[gl_InvocationID]; ecPosition3[gl_InvocationID] = ecPosition[gl_InvocationID]; gl_TessLevelOuter[0] = float(4.0); gl_TessLevelOuter[1] = float(4.0); gl_TessLevelOuter[2] = float(4.0); gl_TessLevelInner[0] = float(4.0); } And my Tessellation Evaluation shader: layout(triangles, equal_spacing, ccw) in; in vec3 myNormal[]; in vec4 ecPosition3[]; out vec3 ecNormal; out vec4 ecPosition; void main() { float u = gl_TessCoord.x; float v = gl_TessCoord.y; float w = gl_TessCoord.z; vec3 position = vec4(gl_in[0].gl_Position.xyz * u + gl_in[1].gl_Position.xyz * v + gl_in[2].gl_Position.xyz * w ); vec3 position2 = vec4(ecPosition3[0].xyz * u + ecPosition3[1].xyz * v + ecPosition3[2].xyz * w ); vec3 normal = myNormal[0] * u + myNormal[1] * v + myNormal[2] * w ); ecNormal = normal; gl_Position = vec4(position, 1.0); ecPosition = vec4(position2, 1.0); } Thank you !

Read the article
HLSL - Creating Shadows in 2D

- by richard

The way that I create shadows is by the following technique: http://www.catalinzima.com/2010/07/my-technique-for-the-shader-based-dynamic-2d-shadows/ But I have questions to HLSL. The way that I currently do it is, I have a black and white image, where Black means 'object', and white means 'nothing'. I then distort the image like in the tutorial. I do this with a pixel shader, but instead of rendering to the screen, I render to a texture, back to my application. I then take this, and create the shadows, and then send it back to the graphics card to undo the distortion, after the shadow has been added - this comes back and I have a stencil of shadow. I can put this ontop of the original image and send them back to the graphics card, which then puts them on the screen. To me this is alot of back and forth. Is there a way i can avoid this? The problem that I am having is that I need to basically go through all positions in the texture 3 times, and use the new new texture every time instead of the orginal one. I tried to read up on Passes, but i don't think that i am heading in the right direction there. Help?

Read the article
stdexcept On Android

- by David R.

I'm trying to compile SoundTouch on Android. I started with this configure line: ./configure CPPFLAGS="-I/Volumes/android-build/mydroid/development/ndk/build/platforms/android-3/arch-arm/usr/include/" LDFLAGS="-Wl,-rpath-link=/Volumes/android-build/mydroid/development/ndk/build/platforms/android-3/arch-arm/usr/lib -L/Volumes/android-build/mydroid/development/ndk/build/platforms/android-3/arch-arm/usr/lib -nostdlib -lc" --host=arm-eabi --enable-shared=yes CFLAGS="-nostdlib -O3 -mandroid" host_alias=arm-eabi --no-create --no-recursion Because the Android NDK targets ARM, I also had to change the Makefile to remove the -msse2 flags to progress. When I run 'make', I get: /bin/sh ../../libtool --tag=CXX --mode=compile arm-eabi-g++ -DHAVE_CONFIG_H -I. -I../../include -I../../include -I/Volumes/android-build/mydroid/development/ndk/build/platforms/android-3/arch-arm/usr/include/ -O3 -fcheck-new -I../../include -g -O2 -MT FIRFilter.lo -MD -MP -MF .deps/FIRFilter.Tpo -c -o FIRFilter.lo FIRFilter.cpp libtool: compile: arm-eabi-g++ -DHAVE_CONFIG_H -I. -I../../include -I../../include -I/Volumes/android-build/mydroid/development/ndk/build/platforms/android-3/arch-arm/usr/include/ -O3 -fcheck-new -I../../include -g -O2 -MT FIRFilter.lo -MD -MP -MF .deps/FIRFilter.Tpo -c FIRFilter.cpp -o FIRFilter.o FIRFilter.cpp:46:21: error: stdexcept: No such file or directory FIRFilter.cpp: In member function 'virtual void soundtouch::FIRFilter::setCoefficients(const soundtouch::SAMPLETYPE*, uint, uint)': FIRFilter.cpp:177: error: 'runtime_error' is not a member of 'std' FIRFilter.cpp: In static member function 'static void* soundtouch::FIRFilter::operator new(size_t)': FIRFilter.cpp:225: error: 'runtime_error' is not a member of 'std' make[2]: *** [FIRFilter.lo] Error 1 make[1]: *** [all-recursive] Error 1 make: *** [all-recursive] Error 1 This isn't very surprising, since the -nostdlib flag was required. Android seems to have neither stdexcept nor stdlib. How can I get past this block of compiling SoundTouch? At a guess, there may be some flag I don't know about that I should use. I could refactor the code not to use stdexcept. There may be a way to pull in the original stdexcept source and reference that. I might be able to link to a precompiled stdexcept library.

Read the article
What is the best way to "carve" a terrain created from a heightmap?

- by tigrou

I have a 3d landscape created from a heightmap. I'd like to "carve" some holes in that terrain. That will allow me to create bridges, caverns and tunnels inside it. That operation will be done in the game editor so it doesn't need to be realtime. In the end, rendering is done using traditional polygons. What would be the best/easiest way to do that ? I already think about several solutions : Solution 1 1) Create voxels from the heightmap (very easy). In other words, fill a 3D array like this : voxels[32][32][32] from the heightmap values. 2) Carve holes in the voxels as i want (easy too). 3) Convert voxels to polygons using some iso-surface extraction technique (like marching cubes). 4) Reduce (decimate) polygons created in 3). This technique seems to be the most promising for giving good results (untested). However the problem with marching cubes is that they tends to produce lots of polygons thus reducing them is mandatory. Implementing 4) also seems not trivial, i have read several papers on the web and it seems pretty complex. I was also unable to find an example, code snippet or something to start writing an algorithm for triangle mesh decimation. Maybe there is a special decimation algorithm (simpler) for meshes created from marching cubes ? Solution 2 1) Create some triangle mesh from the heighmap (easy). 2) Apply severals 3D boolean operation (eg: subtraction with a sphere) to carve the mesh. 3) apply some procedure to reduce polygons (optional). Operation 2) seems to be very complex and to be honest i have no idea how to do that. Also applying many boolean operation seems to be slow and will maybe degrade the triangle mesh every time a boolean operation is applied.

Read the article
What collision detection approach for top down car game?

- by nathan

I have a quite advanced top down car game and i use masks to detect collisions. I have the actual designed track (what the player see) with fancy graphics etc. and two other pictures i use as mask for my detection collisions. Each mask has only two colors, white and black and i check each frame if a pixel of the car collide with a black pixel of the masks. This approach works of course but it's not really flexible. Whenever i want to change the look of a track, i have to redraw the mask and it's a real pain. What is the general approach for this kind of game? How can i improve the flexibility of such a mask based approach?

Read the article
Why does Unity3D crash in VirtualBox?

- by FakeRainBrigand

I'm running Unity3D in a virtual instance of Windows, using the Virtual Box software on Linux. I have guest additions installed with DirectX support. I've tried using Windows XP SP3 32-bit, and Windows 7 64bit. My host is Ubuntu 12.04 64bit. I installed and registered Unity on both. It loads up fine, and then crashes my entire VirtualBox instance (equivalent of a computer shutting off with no warning).

Read the article
matrix 4x4 position data

- by freefallr

I understand that a 4x4 matrix holds rotation and position data. The rotation data is held in the 3x3 sub-matrix at the top left of the matrix. The position data is held in the last column of the matrix. e.g. glm::vec3 vParentPos( mParent[3][0], mParent[3][1], mParent[3][2] ); My question is - am I accessing the parent matrix correctly in the example above? I know that opengl uses a different matrix ordering that directx, (row order instead of column order or something), so, should the mParent be accessed as follows instead? glm::vec3 vParentPos( mParent[0][3], mParent[1][3], mParent[2][3] ); thanks!

Read the article
2D XNA C#: Texture2D Wrapping Issue

- by Kieran

Working in C#/XNA for a Windows game: I'm using Texture2D to draw sprites. All of my sprites are 16 x 32. The sprites move around the screen as you would expect, by changing the top X/Y position of them when they're being drawn by the spritebatch. Most of the time when I run the game, the sprites appear like this: and when moved, they move as I expect, as one element. Infrequently they appear like this: and when moved it's like there are two sprites with a gap in between them - it's hard to describe. It only seems to happen sometimes - is there something I'm missing? I'd really like to know why this is happening. [Edit:] Adding Draw code as requested: This is the main draw routine - it first draws the sprite to a RenderTarget then blows it up by a scale of 4: protected override void Draw(GameTime gameTime) { // Draw to render target GraphicsDevice.SetRenderTarget(renderTarget); GraphicsDevice.Clear(Color.CornflowerBlue); Texture2D imSprite = null; spriteBatch.Begin(SpriteSortMode.FrontToBack, null, SamplerState.PointWrap, null, null); ManSprite.Draw(spriteBatch); base.Draw(gameTime); spriteBatch.End(); // Draw render target to screen GraphicsDevice.SetRenderTarget(null); imageFrame = (Texture2D)renderTarget; GraphicsDevice.Clear(ClearOptions.Target | ClearOptions.DepthBuffer, Color.DarkSlateBlue, 1.0f, 0); spriteBatch.Begin(SpriteSortMode.FrontToBack, null, SamplerState.PointClamp, null, null); spriteBatch.Draw(imageFrame, new Vector2(0, 0), null, Color.White, 0, new Vector2(0, 0), IM_SCALE, SpriteEffects.None, 0); spriteBatch.End(); } This is the draw routine for the Sprite class: public virtual void Draw(SpriteBatch spriteBatch) { spriteBatch.Draw(Texture, new Vector2(PositionX, PositionY), null, Color.White, 0.0f, Vector2.Zero, Scale, SpriteEffects.None, 0.3f); }

Read the article
Rotating an object about a point (2D) using box2d

- by noob

i just started developing using box2d on flixel and i realise the pivot point of the rotation of an object in box2d is set to the center of an object. i had read on forums and i found out that SetAsBox can change the pivot point of the object, however, i cannot seem to get it work to rotate about a point. what i would like to achieve is to rotate an object about a point like earth revolving around the sun. any one can help me with it? really thanks a lot and sorry for the bad english

Read the article
SpriteFont Exception, no such character?

- by Michal Bozydar Pawlowski

I have such spriteFont: <?xml version="1.0" encoding="utf-8"?>  <XnaContent xmlns:Graphics="Microsoft.Xna.Framework.Content.Pipeline.Graphics"> <Asset Type="Graphics:FontDescription">  <FontName>Segoe UI</FontName>  <Size>20</Size>  <Spacing>0</Spacing>  <UseKerning>true</UseKerning>  <Style>Regular</Style>    <CharacterRegions> <CharacterRegion> <Start>	</Start> <End>	</End> </CharacterRegion> <CharacterRegion> <Start> </Start> <End>Ұ</End> </CharacterRegion> </CharacterRegions> </Asset> </XnaContent> It has the character regions (32-1200) And I get this exception: A first chance exception of type 'System.ArgumentException' occurred in Microsoft.Xna.Framework.Graphics.ni.dll The character '?' (0x0441) is not available in this SpriteFont. If applicable, adjust the font's start and end CharacterRegions to include this character. Parameter name: character Why? I'm drawing the string like this: spriteBatch.DrawString(font24, zasadyText, zasadyTextPos, kolorCzcionki1, -0.05f, Vector2.Zero, 1.0f, SpriteEffects.None, 0.5f) I even changed the spriteFont to cyrillic: <CharacterRegions> <CharacterRegion> <Start>	</Start> <End>	</End> </CharacterRegion> <CharacterRegion> <Start> </Start> <End>ſ</End> </CharacterRegion> <CharacterRegion> <Start>А</Start> <End>ї</End> </CharacterRegion> </CharacterRegions> </Asset> </XnaContent> and it still doesn't work. I got the (0x441 = char) exception -- EDIT -- Ok, I got the solution. It was a letter mistake in language. I had this: if (jezyk == "ru_RU") { font14 = Content.Load<SpriteFont>("ru_font14"); font24 = Content.Load<SpriteFont>("ru_font24"); font12 = Content.Load<SpriteFont>("ru_czcionkaFloty"); font10 = Content.Load<SpriteFont>("ru_font10"); font28 = Content.Load<SpriteFont>("ru_font28"); font20 = Content.Load<SpriteFont>("ru_font20"); } else { font14 = Content.Load<SpriteFont>("font14"); font24 = Content.Load<SpriteFont>("font24"); font12 = Content.Load<SpriteFont>("czcionkaFloty"); font10 = Content.Load<SpriteFont>("font10"); font28 = Content.Load<SpriteFont>("font28"); font20 = Content.Load<SpriteFont>("font20"); } and there should be not "ru_RU" but "ru-RU" I have no idea. I changed the spriteFont to cyrillic: <CharacterRegions> <CharacterRegion> <Start>	</Start> <End>	</End> </CharacterRegion> <CharacterRegion> <Start> </Start> <End>ſ</End> </CharacterRegion> <CharacterRegion> <Start>А</Start> <End>ї</End> </CharacterRegion> </CharacterRegions> </Asset> </XnaContent> and it still doesn't work. I got the (0x441 = char) exception

Read the article
Deserialize inherited classes into the same list in XNA

- by M0rgenstern

I am writing a Gui for a game (for what else ...). Therefor I wrote a class GuiElement which has some serializeable fields. From this class I deflect a Class "Button" which has one serializeable field more. Furthermore, I have a Class GuiWindow, which is as well deflected from "GuiElement". An Object of this Class has a Field "HandledElements" of the type "List". To know the layout of the Menues, I use XML-Files, which look like that (for example): <?xml version="1.0" encoding="utf-8" ?> <XnaContent xmlns:Generic="System.Collections.Generic"> <Asset Type="System.Collections.Generic.List[GUI.GuiWindow]"> <Item> <Position>0 0</Position> <AlternativeImagePath></AlternativeImagePath> <IsActive>true</IsActive> <Name>MainMenu</Name> <HandledElements> <Item> <Position>100 100</Position> <AlternativeImagePath></AlternativeImagePath> <IsActive>true</IsActive> <Name>Optionen</Name> <Caption>Optionen</Caption> </Item> </HandledElements> </Item> <Item> <Position>0 0</Position> <AlternativeImagePath></AlternativeImagePath> <IsActive>false</IsActive> <Name>Options</Name> <HandledElements> </HandledElements> </Item> </Asset> </XnaContent> As you can see, the first window has in its "HandledElements" List an Item with the Field . This is a field which only a Button has. The Problem is now: I can't deserialize this XML file, because GuiElement does not have this Field, it only has the few fields above. I thought it would know automatically which Class to use,but it doesn't. Do I really have to give my windows a list for each child class of GuiElement? Or can I do another workaround?

Read the article
OpenGL Shading Program Object Memory Requirement

- by Hans Wurst

gDEbugger states that OpenGL's program objects only occupy an insignificant amount of memory. How much is this actually? I don't know if the stuff I looked up in mesa is actually that I was looking for but it requires 16KB [Edit: false, confusing struct names, less than 1KB immediate, some further behind pointers] per program object. Not quite insignificant. So is it recommended to create a unique program object for each object of the scene? Or to share a single program object and set the scene's object's custom variables just before its draw call?

Read the article

< Previous Page | 545 546 547 548 549 550 551 552 553 554 555 556 | Next Page >