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  • How to use the float value from Noise function in voxel terrain?

    - by therealjohn
    Im using Unity, although this question is not really specific to that engine. Im also using an asset from the store called Coherent Noise. It has some neat noise functionality built it. I am using those functions to produce some noise values. I am getting a value between 0 and 1 (floats). I have an array of blocks (for minecraft like voxel terrain) and I am confused on how to use this float value for terrain? Do I do something like <= 0 == Solid block etc etc? I am confused on how to use the floating values that the noise functions produce to use for height values of an array of say a height of 16. Thanks for any guidance.

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  • Safe zone implementation in Asteroids

    - by Moaz
    I would like to implement a safe zone for asteroids so that when the ship gets destroyed, it shouldn't be there unless it is safe from other asteroids. I tried to check the distance between each asteroid and the ship, and if it is above threshold, it sets a flag to the ship that's a safe zone, but sometimes it work and sometimes it doesn't. What am I doing wrong? Here's my code: for (list<Asteroid>::iterator itr_astroid = asteroids.begin(); itr_astroid!=asteroids.end(); ) { if(currentShip.m_state == Ship::Ship_Dead) { float distance = itr_astroid->getCenter().distance(Vec2f(getWindowWidth()/2,getWindowHeight()/2)); if( distance>200) { currentShip.m_saveField = true; break; } else { currentShip.m_saveField = false; itr_astroid++; } } else { itr_astroid++; } } At ship's death: if(m_state == Ship_Dead && m_saveField==true) { --m_lifeSpan; } if(m_lifeSpan<=0 && m_saveField == true) { m_state = Ship_Alive; m_Vel = Vec2f(0,0); m_Pos.x = app::getWindowWidth()/2; m_Pos.y = app::getWindowHeight()/2; m_lifeSpan = 100; }

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  • Boat passing under a bridge in a 2D tile based RTS

    - by aleguna
    I'm writing a 2D tile based RTS. And I want to add a 'pseudo 3D' feature to it - bridges over the rivers. I havent't start any coding yet, just trying to think how it fits the collision detection model. A boat passing under the bridge and a unit moving over the bridge will eventually occupy the same cell on the map. How to prement them from colliding? Is there a common approach to solve such a problem? Or I need to implement a 3D world to do this?

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  • How to detect which edges of a rectange touch when they collide in iOS

    - by Mike King
    I'm creating a basic "game" in iOS 4.1. The premise is simple, there is a green rectangle ("disk") that moves/bounces around the screen, and red rectangle ("bump") that is stationary. The user can move the red "bump" by touching another coordinate on the screen, but that's irrelevant to this question. Each rectangle is a UIImageView (I will replace them with some kind of image/icon once I get the mechanics down). I've gotten as far as detecting when the rectangles collide, and I'm able to reverse the direction of the green "disk" on the Y axis if they do. This works well when the green "disk" approaches the red "bump" from top or bottom, it bounces off in the other direction. But when it approaches from the side, the bounce is incorrect; I need to reverse the X direction instead. Here's the timer I setup: - (void)viewDidLoad { xSpeed = 3; ySpeed = -3; gameTimer = [NSTimer scheduledTimerWithTimeInterval:0.05 target:self selector:@selector(mainGameLoop:) userInfo:nil repeats:YES]; [super viewDidLoad]; } Here's the main game loop: - (void) mainGameLoop:(NSTimer *)theTimer { disk.center = CGPointMake(disk.center.x + xSpeed, disk.center.y + ySpeed); // make sure the disk does not travel off the edges of the screen // magic number values based on size of disk's frame // startAnimating causes the image to "pulse" if (disk.center.x < 55 || disk.center.x > 265) { xSpeed = xSpeed * -1; [disk startAnimating]; } if (disk.center.y < 55 || disk.center.y > 360) { ySpeed = ySpeed * -1; [disk startAnimating]; } // check to see if the disk collides with the bump if (CGRectIntersectsRect(disk.frame, bump.frame)) { NSLog(@"Collision detected..."); if (! [disk isAnimating]) { ySpeed = ySpeed * -1; [disk startAnimating]; } } } So my question is: how can I detect whether I need to flip the X speed or the Y speed? ie: how can I calculate which edge of the bump was collided with?

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  • Skip the first RenderTarget when writing to MRT with Opaque blending

    - by cubrman
    I am writing to three rendertargets and whant to know how to tell a GPU not to write to the first RT. When you write a shader you can simply output less data than you have RTs (like output a single float4 when writing to three RTs) and only the first RTs will be affected, but you cannot specify to output this data anywhere else but to COLOR0, then 1, etc. Is there a way to write to several RTs but skip the first target? If I output zeroes, the data in the target will become zeroes, but I need it to remain untuched in the first target and only change in the specified ones. The reason I need this is to prevent data loss when calling SetRendertarget() with DiscardContents RTs. I write to all the RTs at one point and I need to write to only the specified ones afterwards. It must be the first texture as I have a depth buffer linked to it (XNA 4.0). Thanks.

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  • How to loop section from a song correctly?

    - by Teflo
    I'm programming a little Music Engine for my game in C# and XNA, and one aspect from it is the possibility to loop a section from a song. For example, my song has an intropart, and when the song reached the end ( or any other specific point ), it jumps back where the intropart is just over. ( A - B - B - B ... ) Now I'm using IrrKlank, which is working perfectly, without any gaps, but I have a problem: The point where to jump back is a bit inaccurate. Here's some example code: public bool Passed(float time) { if ( PlayPosition >= time ) return true; return false; } //somewhere else if( song.Passed( 10.0f ) ) song.JumpTo( 5.0f ); Now the problem is, the song passes the 10 seconds, but play a few milliseconds until 10.1f or so, and then jumps to 5 seconds. It's not that dramatic, but very incorrect for my needs. I tried to fix it like that: public bool Passed( float time ) { if( PlayPosition + 3 * dt >= time && PlayPosition <= time ) return true; return false; } ( dt is the delta time, the elapsed time since the last frame ) But I don't think, that's a good solution for that. I hope, you can understand my problem ( and my english, yay /o/ ) and help me :)

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  • A good way to build a game loop in OpenGL

    - by Jeff
    I'm currently beginning to learn OpenGL at school, and I've started making a simple game the other day (on my own, not for school). I'm using freeglut, and am building it in C, so for my game loop I had really just been using a function I made passed to glutIdleFunc to update all the drawing and physics in one pass. This was fine for simple animations that I didn't care too much about the frame rate, but since the game is mostly physics based, I really want to (need to) tie down how fast it's updating. So my first attempt was to have my function I pass to glutIdleFunc (myIdle()) to keep track of how much time has passed since the previous call to it, and update the physics (and currently graphics) every so many milliseconds. I used timeGetTime() to do this (by using <windows.h>). And this got me to thinking, is using the idle function really a good way of going about the game loop? My question is, what is a better way to implement the game loop in OpenGL? Should I avoid using the idle function?

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  • Resources on expected behaviour when manipulating 3D objects with the mouse

    - by sebf
    Hello, In my animation editor, I have a 3D gizmo that sits on the origin of a bone; the user drags the mesh around to rotate the bone. I've found that translating the 2D movements of the mouse into sensible 3D transforms is not near as simple as i'd hoped. For example what is intuitively 'up' or 'down'? How should the magnitude of rotations change with respect to dX/dY? How to implement this? What happens when the gizmo changes position or orientation with respect to the camera? ect. So far with trial and error i've written something (very) simple that works 70% of the time. I could probably continue to hack at it until I made something that works 99% of the time, but there must be someone who needed the same thing, and spent the time coming up with a much more elegant solution. Does anyone know of one?

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  • Algorithm for creating spheres?

    - by Dan the Man
    Does anyone have an algorithm for creating a sphere proceduraly with la amount of latitude lines, lo amount of longitude lines, and a radius of r? I need it to work with Unity, so the vertex positions need to be defined and then, the triangles defined via indexes (more info). EDIT I managed to get the code working in unity. But I think I might have done something wrong. When I turn up the detailLevel, All it does is add more vertices and polygons without moving them around. Did I forget something?

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  • Comparing angles and working out the difference

    - by Thomas O
    I want to compare angles and get an idea of the distance between them. For this application, I'm working in degrees, but it would also work for radians and grads. The problem with angles is that they depend on modular arithmetic, i.e. 0-360 degrees. Say one angle is at 15 degrees and one is at 45. The difference is 30 degrees, and the 45 degree angle is greater than the 15 degree one. But, this breaks down when you have, say, 345 degrees and 30 degrees. Although they compare properly, the difference between them is 315 degrees instead of the correct 45 degrees. How can I solve this? I could write algorithmic code: if(angle1 > angle2) delta_theta = 360 - angle2 - angle1; else delta_theta = angle2 - angle1; But I'd prefer a solution that avoids compares/branches, and relies entirely on arithmetic.

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  • Tools for creating assets? [closed]

    - by Agent_9191
    There are similar questions about finding existing resources that are free for use (free sprites/images, music, sound), but I'm interested in creating the resources myself. What tools do you use for asset creation/modification? Please only put one tool per answer. Also try to include the following information: Product Name Link to website Type of assets is can create (2D images, 3D images, audio, etc) OS(s) supported Cost License (if free/open source) General summary

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  • Sending changes to a terrain heightmap over UDP

    - by Floomi
    This is a more conceptual, thinking-out-loud question than a technical one. I have a 3D heightmapped terrain as part of a multiplayer RTS that I would like to terraform over a network. The terraforming will be done by units within the gameworld; the player will paint a "target heightmap" that they'd like the current terrain to resemble and units will deform towards that on their own (a la Perimeter). Given my terrain is 257x257 vertices, the naive approach of sending heights when they change will flood the bandwidth very quickly - updating a quarter of the terrain every second will hit ~66kB/s. This is clearly way too much. My next thought was to move to a brush-based system, where you send e.g. the centre of a circle, its radius, and some function defining the influence of the brush from the centre going outwards. But even with reliable UDP the "start" and "stop" messages could still be delayed. I guess I could compare timestamps and compensate for this, although it'd likely mean that clients would deform verts too much on their local simulations and then have to smooth them back to the correct heights. I could also send absolute vert heights in the "start" and "stop" messages to guarantee correct data on the clients. Alternatively I could treat brushes in a similar way to units, and do the standard position + velocity + client-side prediction jazz on them, with the added stipulation that they deform terrain within a certain radius around them. The server could then intermittently do a pass and send (a subset of) recently updated verts to clients as and when there's bandwidth to spare. Any other suggestions, or indications that I'm on the right (or wrong!) track with any of these ideas would be greatly appreciated.

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  • GLSL billboard move center of rotation

    - by Jacob Kofoed
    I have successfully set up a billboard shader that works, it can take in a quad and rotate it so it always points toward the screen. I am using this vertex-shader: void main(){ vec4 tmpPos = (MVP * bufferMatrix * vec4(0.0, 0.0, 0.0, 1.0)) + (MV * vec4( vertexPosition.x * 1.0 * bufferMatrix[0][0], vertexPosition.y * 1.0 * bufferMatrix[1][1], vertexPosition.z * 1.0 * bufferMatrix[2][2], 0.0) ); UV = UVOffset + vertexUV * UVScale; gl_Position = tmpPos; BufferMatrix is the model-matrix, it is an attribute to support Instance-drawing. The problem is best explained through pictures: This is the start position of the camera: And this is the position, looking in from 45 degree to the right: Obviously, as each character is it's own quad, the shader rotates each one around their own center towards the camera. What I in fact want is for them to rotate around a shared center, how would I do this? What I have been trying to do this far is: mat4 translation = mat4(1.0); translation = glm::translate(translation, vec3(pos)*1.f * 2.f); translation = glm::scale(translation, vec3(scale, 1.f)); translation = glm::translate(translation, vec3(anchorPoint - pos) / vec3(scale, 1.f)); Where the translation is the bufferMatrix sent to the shader. What I am trying to do is offset the center, but this might not be possible with a single matrix..? I am interested in a solution that doesn't require CPU calculations each frame, but rather set it up once and then let the shader do the billboard rotation. I realize there's many different solutions, like merging all the quads together, but I would first like to know if the approach with offsetting the center is possible. If it all seems a bit confusing, it's because I'm a little confused myself.

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  • How to automatically render all opaque meshes with a specific shader?

    - by dsilva.vinicius
    I have a specular outline shader that I want to be used on all opaque meshes of the scene whenever a specific camera renders. The shader is working properly when it is manually applied to some material. The shader is as follows: Shader "Custom/Outline" { Properties { _Color ("Main Color", Color) = (.5,.5,.5,1) _OutlineColor ("Outline Color", Color) = (1,0.5,0,1) _Outline ("Outline width", Range (0.0, 0.1)) = .05 _SpecColor ("Specular Color", Color) = (0.5, 0.5, 0.5, 1) _Shininess ("Shininess", Range (0.03, 1)) = 0.078125 _MainTex ("Base (RGB) Gloss (A)", 2D) = "white" {} } SubShader { Tags { "Queue"="Overlay" "RenderType"="Opaque" } Pass { Name "OUTLINE" Tags { "LightMode" = "Always" } Cull Off ZWrite Off // Uncomment to show outline always. //ZTest Always CGPROGRAM #pragma target 3.0 #pragma vertex vert #pragma fragment frag #include "UnityCG.cginc" struct appdata { float4 vertex : POSITION; float3 normal : NORMAL; }; struct v2f { float4 pos : POSITION; float4 color : COLOR; }; float _Outline; float4 _OutlineColor; v2f vert(appdata v) { // just make a copy of incoming vertex data but scaled according to normal direction v2f o; o.pos = mul(UNITY_MATRIX_MVP, v.vertex); float3 norm = mul ((float3x3)UNITY_MATRIX_IT_MV, v.normal); float2 offset = TransformViewToProjection(norm.xy); o.pos.xy += offset * o.pos.z * _Outline; o.color = _OutlineColor; return o; } float4 frag(v2f fromVert) : COLOR { return fromVert.color; } ENDCG } UsePass "Specular/FORWARD" } FallBack "Specular" } The camera used fot the effect has just a script component which setups the shader replacement: using UnityEngine; using System.Collections; public class DetectiveEffect : MonoBehaviour { public Shader EffectShader; // Use this for initialization void Start () { this.camera.SetReplacementShader(EffectShader, "RenderType=Opaque"); } // Update is called once per frame void Update () { } } Unfortunately, whenever I use this camera I just see the background color. Any ideas?

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  • Confusion with Libgdx UI

    - by BrotherJack
    I've started with Libgdx and am currently stumbling about trying to understand how to set up the interface. I have generated the base projects in Eclipse ( < proj-name ,< proj-name -android, < proj-name -desktop, < proj-name -html), and can get the program to display a simple background, play a looping sound file, and draw a tank. I have been having some problems implementing the UI though. I want to make a collapsible interface bar at the bottom of the screen that would contain buttons for movement, and selecting weapons. I'm confused since there appears to be several ways of doing this and the documentation (or tutorials explaining it) tend to be obsolete. How would one go about this? Use a stage for the bar and actors for the widgets? I'm a little lost on this.

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  • How can I solve the same problems a CB-architecture is trying to solve without using hacks? [on hold]

    - by Jefffrey
    A component based system's goal is to solve the problems that derives from inheritance: for example the fact that some parts of the code (that are called components) are reused by very different classes that, hypothetically, would lie in a very different branch of the inheritance tree. That's a very nice concept, but I've found out that CBS is often hard to accomplish without using ugly hacks. Implementations of this system are often far from clean. But I don't want to discuss this any further. My question is: how can I solve the same problems a CBS try to solve with a very clean interface? (possibly with examples, there are a lot of abstract talks about the "perfect" design already). Here's an example I was going for before realizing I was just reinventing inheritance again: class Human { public: Position position; Movement movement; Sprite sprite; // other human specific components }; class Zombie { Position position; Movement movement; Sprite sprite; // other zombie specific components }; After writing that I realized I needed an interface, otherwise I would have needed N containers for N different types of objects (or to use boost::variant to gather them all together). So I've thought of polymorphism (move what systems do in a CBS design into class specific functions): class Entity { public: virtual void on_event(Event) {} // not pure virtual on purpose virtual void on_update(World) {} virtual void on_draw(Window) {} }; class Human { private: Position position; Movement movement; Sprite sprite; public: virtual void on_event(Event) { ... } virtual void on_update(World) { ... } virtual void on_draw(Window) { ... } }; class Zombie { private: Position position; Movement movement; Sprite sprite; public: virtual void on_event(Event) { ... } virtual void on_update(World) { ... } virtual void on_draw(Window) { ... } }; Which was nice, except for the fact that now the outside world would not even be able to know where a Human is positioned (it does not have access to its position member). That would be useful to track the player position for collision detection or if on_update the Zombie would want to track down its nearest human to move towards him. So I added const Position& get_position() const; to both the Zombie and Human classes. And then I realized that both functionality were shared, so it should have gone to the common base class: Entity. Do you notice anything? Yes, with that methodology I would have a god Entity class full of common functionality (which is the thing I was trying to avoid in the first place).

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  • Changing Ogre3D terrain lighting in real time

    - by lezebulon
    I'm looking at the Ogre 3D library and I'm browsing through some examples / tutorials. My question is about terrain. There are a few examples showing how great the terrain system is, but I think that the global illumination and shadows of the terrain have to be pre-computed, which kinda makes it impossible to integrate this with a day / night cycle. Is there a way to change the terrain light sources in real time? If so it is possible to do it and keep a decent FPS?

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  • andengine - how to make the game wait for an animation to finish?

    - by petervaz
    I'm teaching myself andengine while trying to make a match-3 puzzle, so far I have a grid of gems that I populate and can move then around. Matching gems and new gems falling is working already. My problem is that the game keeps flowing while animations runs. How can I make the flow suspend until movement is done? I use entity modifiers for the gems animations. MoveYModifier for the fall and PathModifier for the swap.

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  • Getting an OBB out of another OBB?

    - by Milo
    I'm working on collision resolution for my game. I just need a good way to get an object out of another object if it gets stuck. In this case a car. Here is a typical scenario. The red car is in the green object. How do I correctly get it out so the car can slide along the edge of the object as it should. I tried: if(buildings.size() > 0) { Entity e = buildings.get(0); Vector2D vel = new Vector2D(); vel.x = vehicle.getVelocity().x; vel.y = vehicle.getVelocity().y; vel.normalize(); while(vehicle.getRect().overlaps(e.getRect())) { vehicle.setCenter(vehicle.getCenterX() - vel.x * 0.1f, vehicle.getCenterY() - vel.y * 0.1f); } colided = true; } But that does not work too well. Is there some sort of vector I could calculate to use as the vector to move the car away from the object? Thanks

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  • Turn based battle and formula

    - by Mark Chapman
    I'm building a game called DVP(Digimon Virtual Pet), and in this game other than taking care of your digimon, You can also battle and breed them. I'm working on the battle system (making it first cause the actual pet system will be easy compared to the netplay, or 39DLL)but here is the problem I don't want it to be "too" simple or "too" complicated, but I do want to go by a certain formula. There are str, def, spd, and int. Strength: How hard the attacking digimon is hitting Defense: How much damage your digimon can defend when being attacked Speed: The chance of you missing the enemy Intelligence (battle knowledge): The chance of you hitting a critical hit or defending a critical hit. I can make a super simple turn based example, but I don't know how exactly to make the formulas for what I've explained above, any help?

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  • Drawing an outline around an arbitrary group of hexagons

    - by Perky
    Is there an algorithm for drawing an outline around around an arbitrary group of hexagons? The polygon outline drawn may be concave. See the images below, the green line is what I am trying to achieve. The hexagons are stored as vertices and drawn as polygons. Edit: I've uploaded images that should explain more. I want to favour convex hulls because it's conveys an area of control more quickly. Each hexagon is stored in a multidimensional array so they all have x and y coordinates, I can easily find adjacent hexagons and the opposite vertex, i.e. adjacentHexagon = getAdjacentHexagon( someHexagon, NORTHWEST ) if there isn't a hexagon immediately adjacent it will continue to search in that direction until it finds one or hits the map edges.

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  • Drawing an animation over an already drawn screen

    - by Chandan Pednekar
    I am working on a XNA WP7 card game whose basic prototype is complete. In game screen, 6 cards are displayed at a time (3 for each of the two players say 1,2 and 3). If player A attacks one of player B's card then I want to show an animation over player B's card i.e the victim card(say a claw scratch for e.g.) My question is how do I approach with the animation system so that I can draw an animation over a card upon certain events e.g. dead, fire, claw attack etc. I have an attack function which detects which type of card is attacking which type of card. Depending on the type of attacker card I want to display the animation on the victim card. Can I call animation classes function for different animations in the attack function itself without actually having to call separate draw and update functions. If so, how? Also how do I play sound at the same time when the animation is going on?

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  • Android : glowing/pulsing line/triangle

    - by AndroidGecko
    I would like to create a simple Android app using Opengl ES 2.0 that is showing a simple shape (like line or triangle) that is glowing and pulsing like Nexus X logo in this video : http://youtu.be/jBKVAfZUFqI?t=59s What should I look for? So far I googled around for glowing effects and found techniques like "bloom" or "additive blending". Are they relevant here? how I would implement pulsing glow with them? Any links to relevant works very appreciated Thanks! P.S - I am very familiar with Android SDK; just started with OpenGL ES

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  • Octree subdivision problem

    - by ChaosDev
    Im creating octree manually and want function for effectively divide all nodes and their subnodes - For example - I press button and subnodes divided - press again - all subnodes divided again. Must be like - 1 - 8 - 64. The problem is - i dont understand how organize recursive loops for that. OctreeNode in my unoptimized implementation contain pointers to subnodes(childs),parent,extra vector(contains dublicates of child),generation info and lots of information for drawing. class gOctreeNode { //necessary fields gOctreeNode* FrontBottomLeftNode; gOctreeNode* FrontBottomRightNode; gOctreeNode* FrontTopLeftNode; gOctreeNode* FrontTopRightNode; gOctreeNode* BackBottomLeftNode; gOctreeNode* BackBottomRightNode; gOctreeNode* BackTopLeftNode; gOctreeNode* BackTopRightNode; gOctreeNode* mParentNode; std::vector<gOctreeNode*> m_ChildsVector; UINT mGeneration; bool mSplitted; bool isSplitted(){return m_Splitted;} .... //unnecessary fields }; DivideNode of Octree class fill these fields, set mSplitted to true, and prepare for correctly drawing. Octree contains basic nodes(m_nodes). Basic node can be divided, but now I want recursivly divide already divided basic node with 8 subnodes. So I write this function. void DivideAllChildCells(int ix,int ih,int id) { std::vector<gOctreeNode*> nlist; std::vector<gOctreeNode*> dlist; int index = (ix * m_Height * m_Depth) + (ih * m_Depth) + (id * 1);//get index of specified node gOctreeNode* baseNode = m_nodes[index].get(); nlist.push_back(baseNode->FrontTopLeftNode); nlist.push_back(baseNode->FrontTopRightNode); nlist.push_back(baseNode->FrontBottomLeftNode); nlist.push_back(baseNode->FrontBottomRightNode); nlist.push_back(baseNode->BackBottomLeftNode); nlist.push_back(baseNode->BackBottomRightNode); nlist.push_back(baseNode->BackTopLeftNode); nlist.push_back(baseNode->BackTopRightNode); bool cont = true; UINT d = 0;//additional recursive loop param (?) UINT g = 0;//additional recursive loop param (?) LoopNodes(d,g,nlist,dlist); //Divide resulting nodes for(UINT i = 0; i < dlist.size(); i++) { DivideNode(dlist[i]); } } And now, back to the main question,I present LoopNodes, which must do all work for giving dlist nodes for splitting. void LoopNodes(UINT& od,UINT& og,std::vector<gOctreeNode*>& nlist,std::vector<gOctreeNode*>& dnodes) { //od++;//recursion depth bool f = false; //pass through childs for(UINT i = 0; i < 8; i++) { if(nlist[i]->isSplitted())//if node splitted and have childs { //pass forward through tree for(UINT j = 0; j < 8; j++) { nlist[j] = nlist[j]->m_ChildsVector[j];//set pointers to these childs } LoopNodes(od,og,nlist,dnodes); } else //if no childs { //add to split vector dnodes.push_back(nlist[i]); } } } This version of loop nodes works correctly for 2(or 1?) generations after - this will not divide neightbours nodes, only some corners. I need correct algorithm. Screenshot All I need - is correct version of LoopNodes, which can add all nodes for DivideNode.

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  • OpenGL ES 2.0 texture distortion on large geometry

    - by Spruce
    OpenGL ES 2.0 has serious precision issues with texture sampling - I've seen topics with a similar problem, but I haven't seen a real solution to this "distorted OpenGL ES 2.0 texture" problem yet. This is not related to the texture's image format or OpenGL color buffers, it seems like it's a precision error. I don't know what specifically causes the precision to fail - it doesn't seem like it's just the size of geometry that causes this distortion, because simply scaling vertex position passed to the the vertex shader does not solve the issue. Here are some examples of the texture distortion: Distorted Texture (on OpenGL ES 2.0): http://i47.tinypic.com/3322h6d.png What the texture normally looks like (also on OpenGL ES 2.0): http://i49.tinypic.com/b4jc6c.png The texture issue is limited to small scale geometry on OpenGL ES 2.0, otherwise the texture sampling appears normal, but the grainy effect gradually worsens the further the vertex data is from the origin of XYZ(0,0,0) These texture issues do not occur on desktop OpenGL (works fine under Windows XP, Windows 7, and Mac OS X) I've only seen the problem occur on Android, iPhone, or WebGL(which is similar to OpenGL ES 2.0) All textures are power of 2 but the problem still occurs Scaling the vertex data - The values of a vertex's X Y Z location are in the range of: -65536 to +65536 floating point I realized this was large, so I tried dividing the vertex positions by 1024 to shrink the geometry and hopefully get more accurate floating point precision, but this didn't fix or lessen the texture distortion issue Scaling the modelview or scaling the projection matrix does not help Changing texture filtering options does not help Disabling mipmapping, or using GL_NEAREST/GL_LINEAR does nothing Enabling/disabling anisotropic does nothing The banding effect still occurs even when using GL_CLAMP Dividing the texture coords passed to the vertex shader and then multiplying them back to the correct values in the fragment shader, also does not work precision highp sampler2D, highp float, highp int - in the fragment or the vertex shader didn't change anything (lowp/mediump did not work either) I'm thinking this problem has to have been solved at one point - Seeing that OpenGL ES 2.0 -based games have been able to render large-scale, highly detailed geometry

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