Search Results

Search found 19281 results on 772 pages for 'blender game engine'.

Page 425/772 | < Previous Page | 421 422 423 424 425 426 427 428 429 430 431 432  | Next Page >

  • Change collision action

    - by PatrickR
    I have a collision detection and its working fine, the problem is, that whenever my "bird" is hitting a "cloud", the cloud dissapers and i get some points. The same happens for the "sol" which it should, but not with the clouds. How can this be changed ? ive tryed a lot, but can seem to figger it out. Collision Code - (void)update:(ccTime)dt { bird.position = ccpAdd(bird.position, skyVelocity); NSMutableArray *projectilesToDelete = [[NSMutableArray alloc] init]; for (CCSprite *bird in _projectiles) { bird.anchorPoint = ccp(0, 0); CGRect absoluteBox = CGRectMake(bird.position.x, bird.position.y, [bird boundingBox].size.width, [bird boundingBox].size.height); NSMutableArray *targetsToDelete = [[NSMutableArray alloc] init]; for (CCSprite *cloudSprite in _targets) { cloudSprite.anchorPoint = ccp(0, 0); CGRect absoluteBox = CGRectMake(cloudSprite.position.x, cloudSprite.position.y, [cloudSprite boundingBox].size.width, [cloudSprite boundingBox].size.height); if (CGRectIntersectsRect([bird boundingBox], [cloudSprite boundingBox])) { [targetsToDelete addObject:cloudSprite]; } } for (CCSprite *solSprite in _targets) { solSprite.anchorPoint = ccp(0, 0); CGRect absoluteBox = CGRectMake(solSprite.position.x, solSprite.position.y, [solSprite boundingBox].size.width, [solSprite boundingBox].size.height); if (CGRectIntersectsRect([bird boundingBox], [solSprite boundingBox])) { [targetsToDelete addObject:solSprite]; score += 50/2; [scoreLabel setString:[NSString stringWithFormat:@"%d", score]]; } } // NÅR SKYEN BLIVER RAMT AF FUGLEN for (CCSprite *cloudSprite in targetsToDelete) { //[_targets removeObject:cloudSprite]; //[self removeChild:cloudSprite cleanup:YES]; } // NÅR SOLEN BLIVER RAMT AF FUGLEN for (CCSprite *solSprite in targetsToDelete) { [_targets removeObject:solSprite]; [self removeChild:solSprite cleanup:YES]; } if (targetsToDelete.count > 0) { [projectilesToDelete addObject:bird]; } [targetsToDelete release]; } // NÅR FUGLEN BLIVER RAMT AF ALT ANDET for (CCSprite *bird in projectilesToDelete) { //[_projectiles removeObject:bird]; //[self removeChild:bird cleanup:YES]; } [projectilesToDelete release]; }

    Read the article

  • Java keyboard input [on hold]

    - by dØd
    I'm trying to implement a input system that can detect whether a certain key was held or was only pressed briefly. So far I have this: KEY_INTERACTION_TRESHOLD = 400ms //inside a constructor shouldMeasure = true; @Override public void keyPressed(KeyEvent e) { if (shouldMeasure) { startTime = System.currentTimeMillis(); shouldMeasure = false; return; } System.out.println("Button is held down"); e.consume(); } @Override public void keyReleased(KeyEvent e) { if (System.currentTimeMillis() - startTime < KEY_INTERACTION_TRESHOLD) { System.out.println("Button was only pressed briefly"); } startTime = 0; shouldMeasure = true; e.consume(); } Now this works, but the problem is that there is this delay between when I press a key to hold and when the message 'Button is held down' gets displayed. I understand why this delay occurs (for example when you press and hold a letter there will be a similar delay between the first and the second letter printed out), but I would like to somehow avoid it. I'm using only the Java API.

    Read the article

  • Triangulating a partially triangulated mesh (2D)

    - by teodron
    Referring to the above exhibits, this is the scenario I am working with: starting with a planar graph (in my case, a 2D mesh) with a given triangulation, based on a certain criterion, the graph nodes are labeled as RED and BLACK. (A) a subgraph containing all the RED nodes (with edges between only the directly connected neighbours) is formed (note: although this figure shows a tree forming, it may well happen that the subgraph contain loops) (B) Problem: I need to quickly build a triangulation around the subgraph (e.g. as shown in figure C), but under the constraint that I have to keep the already present edges in the final result. Question: Is there a fast way of achieving this given a partially triangulated mesh? Ideally, the complexity should be in the O(n) class. Some side-remarks: it would be nice for the triangulation algorithm to take into account a certain vertex priority when adding edges (e.g. it should always try to build a "1-ring" structure around the most important nodes first - I can implement iteratively such a routine, but it's O(n^2) ). it would also be nice to reflect somehow the "hop distance" when adding edges: add edges first between the nodes that were "closer" to each other given the start topology. Nevertheless, disregarding the remarks, is there an already known scenario similar to this one where a triangulation is built upon a partially given set of triangles/edges?

    Read the article

  • Slick 2d scrolling off screen

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

    Read the article

  • How to properly do weapon cool-down reload timer in multi-player laggy environment?

    - by John Murdoch
    I want to handle weapon cool-down timers in a fair and predictable way on both client on server. Situation: Multiple clients connected to server, which is doing hit detection / physics Clients have different latency for their connections to server ranging from 50ms to 500ms. They want to shoot weapons with fairly long reload/cool-down times (assume exactly 10 seconds) It is important that they get to shoot these weapons close to the cool-down time, as if some clients manage to shoot sooner than others (either because they are "early" or the others are "late") they gain a significant advantage. I need to show time remaining for reload on player's screen Clients can have clocks which are flat-out wrong (bad timezones, etc.) What I'm currently doing to deal with latency: Client collects server side state in a history, tagged with server timestamps Client assesses his time difference with server time: behindServerTimeNs = (behindServerTimeNs + (System.nanoTime() - receivedState.getServerTimeNs())) / 2 Client renders all state received from server 200 ms behind from his current time, adjusted by what he believes his time difference with server time is (whether due to wrong clocks, or lag). If he has server states on both sides of that calculated time, he (mostly LERP) interpolates between them, if not then he (LERP) extrapolates. No other client-side prediction of movement, e.g., to make his vehicle seem more responsive is done so far, but maybe will be added later So how do I properly add weapon reload timers? My first idea would be for the server to send each player the time when his reload will be done with each world state update, the client then adjusts it for the clock difference and thus can estimate when the reload will be finished in client-time (perhaps considering also for latency that the shoot message from client to server will take as well?), and if the user mashes the "shoot" button after (or perhaps even slightly before?) that time, send the shoot event. The server would get the shoot event and consider the time shot was made as the server time when it was received. It would then discard it if it is nowhere near reload time, execute it immediately if it is past reload time, and hold it for a few physics cycles until reload is done in case if it was received a bit early. It does all seem a bit convoluted, and I'm wondering whether it will work (e.g., whether it won't be the case that players with lower ping get better reload rates), and whether there are more elegant solutions to this problem.

    Read the article

  • When mapping the surface of a sphere with tiles, how might you deal with polar distortion?

    - by clweeks
    It's easy to deal with the way locations interact on a clean Cartesian grid. It's just vanilla math. And you can kind of ignore the geometry of the sphere's surface for a bunch of it if you want to just truncate the poles or something. But I keep coming up with ideas for games where the polar space matters. Geo-coded ARGs and global roguelikes and stuff. I want square(ish?) locations -- reasonably representable by square tiles of the same size across the globe, anyway. This has to be a solved problem, right? What are the solutions? ETA: At the equator -- and assuming that your square locations are reasonably small, it's close enough to true that you can get away with having one square in the rows north and south of the most equatorial row. And you could probably get away with that by just hand-waving the difference up to like 45-degrees or so. But eventually, you need to have fewer squares in a pole-ward circumferential row. If I reduce the length of the row by one and offset the squares by 1/2 then they're just like hexes and it's relatively easy to do the coding to keep track of the connections. But as you get pole-ward, it gets more and more extreme. Projecting the surface of the world onto the surface of a cube is tempting. But I figured there must be more elegant solutions already in use. If I did the cube thing (not dissecting it further through geodesy) Are there any pros and cons related to placing the pole at the center of a face or at the vertex of three sides?

    Read the article

  • How to attach two XNA models together?

    - by jeangil
    I go back on unsolved question I asked about attaching two models together, could you give me some help on this ? For example, If I want to attach together Model1 (= Main model) & Model2 ? I have to get the transformation matrix of Model1 and after get the Bone index on Model1 where I want to attach Model2 and then apply some transformation to attach Model2 to Model1 I wrote some code below about this, but It does not work at all !! (6th line of my code seems to be wrong !?) Model1TransfoMatrix=New Matrix[Model1.Bones.Count]; Index=Model1.bone[x].Index; foreach (ModelMesh mesh in Model2.Meshes) { foreach(BasicEffect effect in mesh.effects) { matrix model2Transform = Matrix.CreateScale(0.1.0f)*Matrix.CreateFromYawPitchRoll(x,y,z); effect.World= model2Transform *Model1TransfoMatrix[Index]; effect.view = camera.View; effect.Projection= camera.Projection; } mesh.draw(); }

    Read the article

  • What would be a good filter to create 'magnetic deformers' from a depth map?

    - by sebf
    In my project, I am creating a system for deforming a highly detailed mesh (clothing) so that it 'fits' a convex mesh. To do this I use depth maps of the item and the 'hull' to determine at what point in world space the deviation occurs and the extent. Simply transforming all occluded vertices to the depths as defined by the 'hull' is fairly effective, and has good performance, but it suffers the problem of not preserving the features of the mesh and requires extensive culling to avoid false-positives. I would like instead to generate from the depth deviation map a set of simple 'deformers' which will 'push'* all vertices of the deformed mesh outwards (in world space). This way, all features of the mesh are preserved and there is no need to have complex heuristics to cull inappropriate vertices. I am not sure how to go about generating this deformer set however. I am imagining something like an algorithm that attempts to match a spherical surface to each patch of contiguous deviations within a certain range, but do not know where to start doing this. Can anyone suggest a suitable filter or algorithm for generating deformers? Or to put it another way 'compressing' a depth map? (*Push because its fitting to a convex 'bulgy' humanoid so transforms are likely to be 'spherical' from the POV of the surface.)

    Read the article

  • how can i get rotation vector from matrix4x4 in xna?

    - by mr.Smyle
    i want to get rotation vector from matrix to realize some parent-children system for models. Matrix bonePos = link.Bone.Transform * World; Matrix m = Matrix.CreateTranslation(link.Offset) * Matrix.CreateScale(link.gameObj.Scale.X, link.gameObj.Scale.Y, link.gameObj.Scale.Z) * Matrix.CreateFromYawPitchRoll(MathHelper.ToRadians(link.gameObj.Rotation.Y), MathHelper.ToRadians(link.gameObj.Rotation.X), MathHelper.ToRadians(link.gameObj.Rotation.Z)) //need rotation vector from bone matrix here (now it's global model rotation vector) * Matrix.CreateFromYawPitchRoll(MathHelper.ToRadians(Rotation.Y), MathHelper.ToRadians(Rotation.X), MathHelper.ToRadians(Rotation.Z)) * Matrix.CreateTranslation(bonePos.Translation); link.gameObj.World = m; where : link - struct with children model settings, like position, rotation etc. And link.Bone - Parent Bone

    Read the article

  • Box2d world width and height ratio with screen width and height

    - by Sujith
    I have view, for example GameView which extends SurfaceView . I have integrated Box2D physics in GameView. I have two widths , GameView width, height and Box2D physics world width ,height. I need to get the position of box2d world with the GameView co-ordinates. For example, Total width of screen = 240 Total height of screen = 320 Screen points needed to be mapped onto box2d co-ordinates (x,y) = 127, 139 For this i need to get the max width and height of the Box2d physics world. Is there is any way to get the max width and height of Box2d world. or Can i limit the width and height of box2d world within the screen resolution.

    Read the article

  • Basics of drawing in 2d with OpenGL 3 shaders

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

    Read the article

  • Player sprite moving slower on iPhone 4

    - by nvillec
    I just finished getting movement/jump animation for a player sprite in Xcode using Cocos2D. The basic movement algorithm is a timer that updates every 0.01 sec, changing the sprite position to (sprite.position.x + xVel, sprite.position.y + yVel). Each time a movement button is tapped, the appropriate velocity (initialized to 0) is changed to whatever speed I choose, then a stop movement button returns the velocity to 0. It's not an ideal solution but I'm very new at this and stoked to at least have that working with little help from the internet. So I may not have explained that perfectly, but it is in fact working to my satisfaction in Xcode's iPhone Simulator, however when I build it for my device and run it on my phone, the sprite's movement speed is noticeably slower than in Xcode. At first I thought it must have to do with the resolution of the iPhone 4, making the sprite's movement path twice as long, but I found that if I pull up the multitask bar, then return to the app the speed will sometimes jump back to normal. My second theory was that the code is just inefficient and is bogging the processes down, but I would see this reflected in the frame rate wouldn't I? It stays at 59-60 the whole time, and the spritesheet animation runs at the correct speed. Has anyone experienced this? Is this a really obvious issue that I'm completely missing? Any help (or tips for optimizing my approach to movement) would be much appreciated!

    Read the article

  • Why doesn't my texture display with this GLSL shader?

    - by Chewy Gumball
    I am trying to display a DXT1 compressed texture on a quad using a VBO and shaders, but I have been unable to get it working. All I get is a black square. I know my texture is uploaded properly because when I use immediate mode without shaders the texture displays fine but I will include that part just in case. Also, when I change the gl_FragColor to something like vec4 (0.0, 1.0, 1.0, 1.0) then I get a nice blue quad so I know that my shader is able to set the colour. It appears to be either the texture is not being bound correctly in the shader or the texture coordinates are not being picked up. However, I can't find the error! What am I doing wrong? I am using OpenTK in C# (not xna). Vertex Shader: void main() { gl_TexCoord[0] = gl_MultiTexCoord0; // Set the position of the current vertex gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex; } Fragment Shader: uniform sampler2D diffuseTexture; void main() { // Set the output color of our current pixel gl_FragColor = texture2D(diffuseTexture, gl_TexCoord[0].st); //gl_FragColor = vec4 (0.0,1.0,1.0,1.0); } Drawing Code: int vb, eb; GL.GenBuffers(1, out vb); GL.GenBuffers(1, out eb); // Position Texture float[] verts = { 0.1f, 0.1f, 0.0f, 0.0f, 0.0f, 1.9f, 0.1f, 0.0f, 1.0f, 0.0f, 1.9f, 1.9f, 0.0f, 1.0f, 1.0f, 0.1f, 1.9f, 0.0f, 0.0f, 1.0f }; uint[] indices = { 0, 1, 2, 0, 2, 3 }; //upload data to the VBO GL.BindBuffer(BufferTarget.ArrayBuffer, vb); GL.BindBuffer(BufferTarget.ElementArrayBuffer, eb); GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)(verts.Length * sizeof(float)), verts, BufferUsageHint.StaticDraw); GL.BufferData(BufferTarget.ElementArrayBuffer, (IntPtr)(indices.Length * sizeof(uint)), indices, BufferUsageHint.StaticDraw); //Upload texture int buffer = GL.GenTexture(); GL.BindTexture(TextureTarget.Texture2D, buffer); GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (float)TextureWrapMode.Repeat); GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (float)TextureWrapMode.Repeat); GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (float)TextureMagFilter.Linear); GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (float)TextureMinFilter.Linear); GL.TexEnv(TextureEnvTarget.TextureEnv, TextureEnvParameter.TextureEnvMode, (float)TextureEnvMode.Modulate); GL.CompressedTexImage2D(TextureTarget.Texture2D, 0, texture.format, texture.width, texture.height, 0, texture.data.Length, texture.data); //Draw GL.UseProgram(shaderProgram); GL.EnableClientState(ArrayCap.VertexArray); GL.EnableClientState(ArrayCap.TextureCoordArray); GL.VertexPointer(3, VertexPointerType.Float, 5 * sizeof(float), 0); GL.TexCoordPointer(2, TexCoordPointerType.Float, 5 * sizeof(float), 3); GL.ActiveTexture(TextureUnit.Texture0); GL.Uniform1(GL.GetUniformLocation(shaderProgram, "diffuseTexture"), 0); GL.DrawElements(BeginMode.Triangles, indices.Length, DrawElementsType.UnsignedInt, 0);

    Read the article

  • How to create a copy of an instance without having access to private variables

    - by Jamie
    Im having a bit of a problem. Let me show you the code first: public class Direction { private CircularList xSpeed, zSpeed; private int[] dirSquare = {-1, 0, 1, 0}; public Direction(int xSpeed, int zSpeed){ this.xSpeed = new CircularList(dirSquare, xSpeed); this.zSpeed = new CircularList(dirSquare, zSpeed); } public Direction(Point dirs){ this(dirs.x, dirs.y); } public void shiftLeft(){ xSpeed.shiftLeft(); zSpeed.shiftRight(); } public void shiftRight(){ xSpeed.shiftRight(); zSpeed.shiftLeft(); } public int getXSpeed(){ return this.xSpeed.currentValue(); } public int getZSpeed(){ return this.zSpeed.currentValue(); } } Now lets say i have an instance of Direction: Direction dir = new Direction(0, 0); As you can see in the code of Direction, the arguments fed to the constructor, are passed directly to some other class. One cannot be sure if they stay the same because methods shiftRight() and shiftLeft could have been called, which changes thos numbers. My question is, how do i create a completely new instance of Direction, that is basically copy(not by reference) of dir? The only way i see it, is to create public methods in both CircularList(i can post the code of this class, but its not relevant) and Direction that return the variables needed to create a copy of the instance, but this solution seems really dirty since those numbers are not supposed to be touched after beeing fed to the constructor, and therefore they are private.

    Read the article

  • Help understand GLSL directional light on iOS (left handed coord system)

    - by Robse
    I now have changed from GLKBaseEffect to a own shader implementation. I have a shader management, which compiles and applies a shader to the right time and does some shader setup like lights. Please have a look at my vertex shader code. Now, light direction should be provided in eye space, but I think there is something I don't get right. After I setup my view with camera I save a lightMatrix to transform the light from global space to eye space. My modelview and projection setup: - (void)setupViewWithWidth:(int)width height:(int)height camera:(N3DCamera *)aCamera { aCamera.aspect = (float)width / (float)height; float aspect = aCamera.aspect; float far = aCamera.far; float near = aCamera.near; float vFOV = aCamera.fieldOfView; float top = near * tanf(M_PI * vFOV / 360.0f); float bottom = -top; float right = aspect * top; float left = -right; // projection GLKMatrixStackLoadMatrix4(projectionStack, GLKMatrix4MakeFrustum(left, right, bottom, top, near, far)); // identity modelview GLKMatrixStackLoadMatrix4(modelviewStack, GLKMatrix4Identity); // switch to left handed coord system (forward = z+) GLKMatrixStackMultiplyMatrix4(modelviewStack, GLKMatrix4MakeScale(1, 1, -1)); // transform camera GLKMatrixStackMultiplyMatrix4(modelviewStack, GLKMatrix4MakeWithMatrix3(GLKMatrix3Transpose(aCamera.orientation))); GLKMatrixStackTranslate(modelviewStack, -aCamera.position.x, -aCamera.position.y, -aCamera.position.z); } - (GLKMatrix4)modelviewMatrix { return GLKMatrixStackGetMatrix4(modelviewStack); } - (GLKMatrix4)projectionMatrix { return GLKMatrixStackGetMatrix4(projectionStack); } - (GLKMatrix4)modelviewProjectionMatrix { return GLKMatrix4Multiply([self projectionMatrix], [self modelviewMatrix]); } - (GLKMatrix3)normalMatrix { return GLKMatrix3InvertAndTranspose(GLKMatrix4GetMatrix3([self modelviewProjectionMatrix]), NULL); } After that, I save the lightMatrix like this: [self.renderer setupViewWithWidth:view.drawableWidth height:view.drawableHeight camera:self.camera]; self.lightMatrix = [self.renderer modelviewProjectionMatrix]; And just before I render a 3d entity of the scene graph, I setup the light config for its shader with the lightMatrix like this: - (N3DLight)transformedLight:(N3DLight)light transformation:(GLKMatrix4)matrix { N3DLight transformedLight = N3DLightMakeDisabled(); if (N3DLightIsDirectional(light)) { GLKVector3 direction = GLKVector3MakeWithArray(GLKMatrix4MultiplyVector4(matrix, light.position).v); direction = GLKVector3Negate(direction); // HACK -> TODO: get lightMatrix right! transformedLight = N3DLightMakeDirectional(direction, light.diffuse, light.specular); } else { ... } return transformedLight; } You see the line, where I negate the direction!? I can't explain why I need to do that, but if I do, the lights are correct as far as I can tell. Please help me, to get rid of the hack. I'am scared that this has something to do, with my switch to left handed coord system. My vertex shader looks like this: attribute highp vec4 inPosition; attribute lowp vec4 inNormal; ... uniform highp mat4 MVP; uniform highp mat4 MV; uniform lowp mat3 N; uniform lowp vec4 constantColor; uniform lowp vec4 ambient; uniform lowp vec4 light0Position; uniform lowp vec4 light0Diffuse; uniform lowp vec4 light0Specular; varying lowp vec4 vColor; varying lowp vec3 vTexCoord0; vec4 calcDirectional(vec3 dir, vec4 diffuse, vec4 specular, vec3 normal) { float NdotL = max(dot(normal, dir), 0.0); return NdotL * diffuse; } ... vec4 calcLight(vec4 pos, vec4 diffuse, vec4 specular, vec3 normal) { if (pos.w == 0.0) { // Directional Light return calcDirectional(normalize(pos.xyz), diffuse, specular, normal); } else { ... } } void main(void) { // position highp vec4 position = MVP * inPosition; gl_Position = position; // normal lowp vec3 normal = inNormal.xyz / inNormal.w; normal = N * normal; normal = normalize(normal); // colors vColor = constantColor * ambient; // add lights vColor += calcLight(light0Position, light0Diffuse, light0Specular, normal); ... }

    Read the article

  • Android how to get opengl 3D coordinates in ontouch event

    - by Sandy
    I created a cube in opengl and it rotates in ontouch event. To to this I created a CustomSurfaceView as follows public class CustomSurfaceView extends GLSurfaceView { @Override public boolean onTouchEvent(MotionEvent e) { float x = e.getX() float y = e.getY(); } } Here x and y are screen coordinates. How can I get 3D coordinated from this? I have already looked gluProject and NeHe. But I dont know how to implement this in my project, it shows that there is no GLdouble,GLfloat class.

    Read the article

  • OpenGL ES 2. How do I Create a Basic Fading Streak Effect?

    - by dugla
    For the iPad app I am writing using OpenGL ES 2 I have a single quad - shaded using GLSL - that is dragged around the screen. Very basic. This works fine. But is rather boring. I want to increase the coolness a bit in the following way: when the user drags the quad it leaves a streak behind that fades over time. Continuous dragging would be a bit like a streaking comet across the night sky. What is the simplest way to implement this? Thanks.

    Read the article

  • OpenGL textures trigger error 1281 if SFML is not called

    - by user3714670
    I am using SOIL to apply textures to VBOs, without textures i could change the background and display black (default color) vbos easily, but now with textures, openGL is giving an error 1281, the background is black and some textures are not applied. but the first texture IS applied (nothing else is working though). The strange thing is : if i create a dummy texture with SFML in the same program, all other textures do work. So i guess there is something i forgot in the texture creation/application, if someone could enlighten me. Here is the code i use to load textures, once loaded it is kept in memory, it mostly comes from the example of SOIL : texture = SOIL_load_OGL_single_cubemap( filename, SOIL_DDS_CUBEMAP_FACE_ORDER, SOIL_LOAD_AUTO, SOIL_CREATE_NEW_ID, SOIL_FLAG_POWER_OF_TWO | SOIL_FLAG_MIPMAPS | SOIL_FLAG_DDS_LOAD_DIRECT ); if( texture > 0 ) { glEnable( GL_TEXTURE_CUBE_MAP ); glEnable( GL_TEXTURE_GEN_S ); glEnable( GL_TEXTURE_GEN_T ); glEnable( GL_TEXTURE_GEN_R ); glTexGeni( GL_S, GL_TEXTURE_GEN_MODE, GL_REFLECTION_MAP ); glTexGeni( GL_T, GL_TEXTURE_GEN_MODE, GL_REFLECTION_MAP ); glTexGeni( GL_R, GL_TEXTURE_GEN_MODE, GL_REFLECTION_MAP ); glBindTexture( GL_TEXTURE_CUBE_MAP, texture ); std::cout << "the loaded single cube map ID was " << texture << std::endl; } else { std::cout << "Attempting to load as a HDR texture" << std::endl; texture = SOIL_load_OGL_HDR_texture( filename, SOIL_HDR_RGBdivA2, 0, SOIL_CREATE_NEW_ID, SOIL_FLAG_POWER_OF_TWO | SOIL_FLAG_MIPMAPS ); if( texture < 1 ) { std::cout << "Attempting to load as a simple 2D texture" << std::endl; texture = SOIL_load_OGL_texture( filename, SOIL_LOAD_AUTO, SOIL_CREATE_NEW_ID, SOIL_FLAG_POWER_OF_TWO | SOIL_FLAG_MIPMAPS | SOIL_FLAG_DDS_LOAD_DIRECT ); } if( texture > 0 ) { // enable texturing glEnable( GL_TEXTURE_2D ); // bind an OpenGL texture ID glBindTexture( GL_TEXTURE_2D, texture ); std::cout << "the loaded texture ID was " << texture << std::endl; } else { glDisable( GL_TEXTURE_2D ); std::cout << "Texture loading failed: '" << SOIL_last_result() << "'" << std::endl; } } and how i apply it when drawing : GLuint TextureID = glGetUniformLocation(shaderProgram, "myTextureSampler"); if(!TextureID) cout << "TextureID not found ..." << endl; // glEnableVertexAttribArray(TextureID); glActiveTexture(GL_TEXTURE0); if(SFML) sf::Texture::bind(sfml_texture); else { glBindTexture (GL_TEXTURE_2D, texture); // glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 1024, 768, 0, GL_RGB, GL_UNSIGNED_BYTE, &texture); } glUniform1i(TextureID, 0); I am not sure that SOIL is adapted to my program as i want something as simple as possible (i used sfml's texture object which was the best but i can't anymore), but if i can get it to work it would be great.

    Read the article

  • How to derive euler angles from matrix or quaternion?

    - by KlashnikovKid
    Currently working on steering behavior for my AI and just hit a little mathematical bump. I'm in the process of writing an align function, which basically tries to match the agent's orientation with a target orientation. I've got a good source material for implementing this behavior but it uses euler angles to calculate the rotational delta, acceleration, and so on. This is nice, however I store orientation as a quaternion and the math library I'm using doesn't provide any functionality for deriving the euler angles. But if it helps I also have rotational matrices at my disposal too. What would be the best way to decompose the quaternion or rotational matrix to get the euler information? I found one source for decomposing the matrix, but I'm not quite getting the correct results. I'm thinking it may be a difference of column/row ordering of my matrices but then again, math isn't my strong point. http://nghiaho.com/?page_id=846

    Read the article

  • Circle collision detection and Vector math: HELP?

    - by Griffin
    Hey so i'm currently going through the wildbunny blog to learn about collision detection, but i'm a bit confused on how the vectors he's talking about come into play QUOTED BLOG: p = ||A-B|| – (r1+r2) The two spheres are penetrating by distance p. We would also like the penetration vector so that we can correct the penetration once we discover it. This is the vector that moves both circles to the point where they just touch, correcting the penetration. Importantly it is not only just a vector that does this, it is the only vector which corrects the penetration by moving the minimum amount. This is important because we only want to correct the error, not introduce more by moving too much when we correct, or too little. N = (A-B) / ||A-B|| P = N*p Here we have calculated the normalised vector N between the two centres and the penetration vector P by multiplying our unit direction by the penetration distance. Ok so i understand that p is the distance each circle is penetrating each other, but i don't get what exactly N and P is. it seems to me N is just the coordinates of the 3rd point of the right trianlge formed by point A and B (A-B) then being divided by the hypotenuse of that triangle or distance between A and B (||A-B||) Whats the significance of this? Also, what is the penetration vector used for? It seems to me like a movement that one of the circles would perform to get un-penetrated.

    Read the article

  • Debugging HLSL for Windows 8 application [migrated]

    - by Shervanator
    i'm currently in the process of creating a Windows 8 applicaiton using SharpDX (the managed c# directx wrapper). However I have ran into problems with one of my shaders and I want to know if its possible to debug such applications. PIX doesn't seem to work of directX apps as the executable does not like opening directly, and the new visual studio graphics debugging toolkit in VS2012 always states "unable to start the experiment" when I try to capture any information about my session. Thanks!

    Read the article

  • How do i make a minecraft server mod? [closed]

    - by Simon
    Possible Duplicate: Mods for Minecraft Server - how does it work? I have made some minecraft client mods, but i've started a server a mounth ago and i want to make a mod for it, but i cant find any tutorial on the internet. How can then the other guys making those mods for minecraft server know how they are going to do? Do they try forward as i tryed or are they doing something else. I would be glad if someone could tell me how to do or find tutorials for me, couse I have tryed to find them in nearly a week of searching. But i guess im searching at the wrong spot of internet, what do i know :o

    Read the article

  • Using a permutation table for simplex noise without storing it

    - by J. C. Leitão
    Generating Simplex noise requires a permutation table for randomisation (e.g. see this question or this example). In some applications, we need to persist the state of the permutation table. This can be done by creating the table, e.g. using def permutation_table(seed): table_size = 2**10 # arbitrary for this question l = range(1, table_size + 1) random.seed(seed) # ensures the same shuffle for a given seed random.shuffle(l) return l + l # see shared link why l + l; is a detail and storing it. Can we avoid storing the full table by generating the required elements every time they are required? Specifically, currently I store the table and call it using table[i] (table is a list). Can I avoid storing it by having a function that computes the element i, e.g. get_table_element(seed, i). I'm aware that cryptography already solved this problem using block cyphers, however, I found it too complex to go deep and implement a block cypher. Does anyone knows a simple implementation of a block cypher to this problem?

    Read the article

  • Drawing different per-pixel data on the screen

    - by Amir Eldor
    I want to draw different per-pixel data on the screen, where each pixel has a specific value according to my needs. An example may be a random noise pattern where each pixel is randomly generated. I'm not sure what is the correct and fastest way to do this. Locking a texture/surface and manipulating the raw pixel data? How is this done in modern graphics programming? I'm currently trying to do this in Pygame but realized I will face the same problem if I go for C/SDL or OpenGL/DirectX.

    Read the article

  • How to perform efficient 2D picking in HTML5?

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

    Read the article

< Previous Page | 421 422 423 424 425 426 427 428 429 430 431 432  | Next Page >