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  • How to make my simple round sprite look right in XNA

    - by Joshua Perina
    Ok, I'm very new to graphics programming (but not new to coding). I'm trying to load a simple image in XNA which I can do fine. It is a simple round circle which I made in photoshop. The problem is the edges show up rough when I draw it on the screen even with the exact size. The anti-aliasing is missing. I'm sure I'm missing something very simple: GraphicsDevice.Clear(Color.Black); // TODO: Add your drawing code here spriteBatch.Begin(); spriteBatch.Draw(circle, new Rectangle(10, 10, 10, 10), Color.White); spriteBatch.End(); Couldn't post picture because I'm a first time poster. But my smooth png circle has rough edges. So I found that if I added: spriteBatch.Begin(SpriteSortMode.FrontToBack, BlendState.NonPremultiplied); I can get a smooth image when the image is the same size as the original png. But if I want to scale that image up or down then the rough edges return. How do I get XNA to smoothly resize my simple round image to a smaller size without getting the rough edges?

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  • Precision loss when transforming from cartesian to isometric

    - by Justin Skiles
    My goal is to display a tile map in isometric projection. This tile map has 25 tiles across and 25 tiles down. Each tile is 32x32. See below for how I'm accomplishing this. World Space World Space to Screen Space Rotation (45 degrees) Using a 2D rotation matrix, I use the following: double rotation = Math.PI / 4; double rotatedX = ((tileWorldX * Math.Cos(rotation)) - ((tileWorldY * Math.Sin(rotation))); double rotatedY = ((tileWorldX * Math.Sin(rotation)) + (tileWorldY * Math.Cos(rotation))); World Space to Screen Space Scale (Y-axis reduced by 50%) Here I simply scale down the Y value by a factor of 0.5. Problem And it works, kind of. There are some tiny 1px-2px gaps between some of the tiles when rendering. I think there's some precision loss somewhere, or I'm not understanding how to get these tiles to fit together perfectly. I'm not truncating or converting my values to non-decimal types until I absolutely have to (when I pass to the render method, which only takes integers). I'm not sure how to guarantee pixel perfect rendering precision when I'm rotating and scaling on a level of higher precision. Any advice? Do I need to supply for information?

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  • vector rotations for branches of a 3d tree

    - by freefallr
    I'm attempting to create a 3d tree procedurally. I'm hoping that someone can check my vector rotation maths, as I'm a bit confused. I'm using an l-system (a recursive algorithm for generating branches). The trunk of the tree is the root node. It's orientation is aligned to the y axis. In the next iteration of the tree (e.g. the first branches), I might create a branch that is oriented say by +10 degrees in the X axis and a similar amount in the Z axis, relative to the trunk. I know that I should keep a rotation matrix at each branch, so that it can be applied to child branches, along with any modifications to the child branch. My questions then: for the trunk, the rotation matrix - is that just the identity matrix * initial orientation vector ? for the first branch (and subsequent branches) - I'll "inherit" the rotation matrix of the parent branch, and apply x and z rotations to that also. e.g. using glm::normalize; using glm::rotateX; using glm::vec4; using glm::mat4; using glm::rotate; vec4 vYAxis = vec4(0.0f, 1.0f, 0.0f, 0.0f); vec4 vInitial = normalize( rotateX( vYAxis, 10.0f ) ); mat4 mRotation = mat4(1.0); // trunk rotation matrix = identity * initial orientation vector mRotation *= vInitial; // first branch = parent rotation matrix * this branches rotations mRotation *= rotate( 10.0f, 1.0f, 0.0f, 0.0f ); // x rotation mRotation *= rotate( 10.0f, 0.0f, 0.0f, 1.0f ); // z rotation Are my maths and approach correct, or am I completely wrong? Finally, I'm using the glm library with OpenGL / C++ for this. Is the order of x rotation and z rotation important?

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  • How do I dynamically reload content files?

    - by Kikaimaru
    Is there a relatively simple way to dynamically reload content files, such as effect files? I know I can do the following: Detect change of file Run content pipeline to rebuild that specific file Unload ALL content that was loaded Load all content And use double references to reference content files. The problem is with step 3 (and step 2 isn't that nice either). I need to unload everything because if I have model Hero.x which references Model.fx effect, and I change the Model.fx file, I need to reload the Hero.x file which will then call LoadExternalReference on Model.fx. Has someone managed to make this work without rewriting the whole ContentManager (and every ContentReader) and tracking calls to LoadExternalReference?

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  • How is the iOS support in UDK compared to Unity?

    - by Joe
    I have some significant experience in Unity for web clients, but I'm skeptical about the 3K$ price tag to create/deploy iOS games. I noticed UDK now supports iOS, and appears to have "free" version control- and it's only 100$ from what I can tell. My primary question is: Does UDK make iOS development and deployment easy, or do you have to jump through a couple of hoops to make it work? A few side questions not worth another post: How hard is the transition from Unity to UDK? Is UnrealScript easy to pick up from a C/C# background? Does the UDK have good documentation compared to Unity?

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  • Getting isometric grid coordinates from standard X,Y coordinates

    - by RoryHarvey
    I'm currently trying to add sprites to an isometric Tiled TMX map using Objects in cocos2d. The problem is the X and Y metadata from TMX object are in standard 2d format (pixels x, pixels y), instead of isometric grid X and Y format. Usually you would just divide them by the tile size, but isometric needs some sort of transform. For example on a 64x32 isometric tilemap of size 40 tiles by 40 tiles an object at (20,21)'s coordinates come out as (640,584) So the question really is what formula gets (20,21) from (640,584)?

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  • Is there a good way to get pixel-perfect collision detection in XNA?

    - by ashes999
    Is there a well-known way (or perhaps reusable bit of code) for pixel-perfect collision detection in XNA? I assume this would also use polygons (boxes/triangles/circles) for a first-pass, quick-test for collisions, and if that test indicated a collision, it would then search for a per-pixel collision. This can be complicated, because we have to account for scale, rotation, and transparency. WARNING: If you're using the sample code from the link from the answer below, be aware that the scaling of the matrix is commented out for good reason. You don't need to uncomment it out to get scaling to work.

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  • Proper updating of GeoClipMaps

    - by thr
    I have been working on an implementation of gpu-based geo clip maps, but there is a section of the GPU Gems 2 article that i just can't seem to understand, specifically this paragraph and more precisely the bolded part: The choice of grid size n = 2k-1 has the further advantage that the finer level is never exactly centered with respect to its parent next-coarser level. In other words, it is always offset by 1 grid unit either left or right, as well as either top or bottom (see Figure 2-4), depending on the position of the viewpoint. In fact, it is necessary to allow a finer level to shift while its next-coarser level stays fixed, and therefore the finer level must sometimes be off-center with respect to the next-coarser level. An alternative choice of grid size, such as n = 2k-3, would provide the possibility for exact centering Let's take an example image from the article: My "understanding" of the way the clip maps were update was that you floor the position of the viewpoint to an int, and such get the center vertex point if this is not the same as the previous center point, you update the entire map. Now, this obviously is not the case - but what I am failing to understand is this: If you look at the image above, if the viewpoint was to move one unit to the right, then the inner ring (the one just around the view point + white center square) would end up getting a 1 unit space on both the left and right side of itself. But there is nothing in the paper that deals with this, what i mean is that it would end up looking like this (excuse my crummy cut-and-paste editing of the above image): This is obviously not a valid state of the. So, would the solution be that a clip ring (layer) can only move in increments of the ring/layer it's contained within? Wouldn't this end up being very restrictive? I feel like I am missing some crucial understanding of parts of the algorithm, but I have been over both this paper and the original paper from 2004 and I just can't see what I am not getting.

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  • Finding closest object to a location within a specific perpendicular distance to direction vector

    - by Sniper
    I have a location and a direction vector indicating facing, I want to find the closest object to that location that is within some tolerance distance (perpendicular distance) to the ray formed by the location and direction vector. Basically I want to get the object that is being aimed at. I have thought about finding all objects within a box and then finding the closest object to my vector from them results, but I am sure that there is a more efficient way. The Z axis is optional, the objects are most likely within a few meters of the search vector.

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  • How stoper one annimation model on XNA?

    - by Mehdi Bugnard
    I met a Difficulty for one stoper annimation. Everything works great starter for the animation. But I do not see how stoper and can continue the annimation paused. The "animationPlayer.StartClip (clip)" is used to choke the annimation but impossible to find a way to stoper Thans's a lot Here is my code to use. protected override void LoadContent() { //Model - Player model_player = Content.Load<Model>("Models\\Player\\models"); // Look up our custom skinning information. SkinningData skinningData = model_player.Tag as SkinningData; if (skinningData == null) throw new InvalidOperationException ("This model does not contain a SkinningData tag."); // Create an animation player, and start decoding an animation clip. animationPlayer = new AnimationPlayer(skinningData); AnimationClip clip = skinningData.AnimationClips["ArmLowAction_006"]; animationPlayer.StartClip(clip); } protected overide update(GameTime gameTime) { KeyboardState key = Keyboard.GetState(); // If player don't move -> stop anim if (!key.IsKeyDown(Keys.W) && !keyStateOld.IsKeyUp(Keys.S) && !keyStateOld.IsKeyUp(Keys.A) && !keyStateOld.IsKeyUp(Keys.D)) { //animation stop ? not exist ? animationPlayer.Stop(); isPlayerStop = true; } else { if(isPlayerStop == true) { isPlayerStop = false; animationPlayer.StartClip(Clip); } }

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  • Vertex Array Object (OpenGL)

    - by Shin
    I've just started out with OpenGL I still haven't really understood what Vertex Array Objects are and how they can be employed. If Vertex Buffer Object are used to store vertex data (such as their positions and texture coordinates) and the VAOs only contain status flags, where can they be used? What's their purpose? As far as I understood from the (very incomplete and unclear) GL Wiki, VAOs are used to set the flags/status for every vertex, following the order described in the Element Array Buffer, but the wiki was really ambiguous about it and I'm not really sure about what VAOs really do and how I could employ them.

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  • Simplest way to render image over top of another with another image used as mask in OpenGL?

    - by Adam Naylor
    The effect I'm looking for is to have a single large background image that is always visible (at full alpha) and then show a second image (what I call a light map or specular map) that is partially shown over the top based on a third image (which is effectively a mask). The effect is similar to this effect except instead of simply darkening or lightening the background image using the third image it needs to mask the second without effecting the first at all. The third image is the only one that moves therefore hard baking the third images alpha into the second image isn't an option. If my explanation isn't clear I'll provide visual examples when I have more time. I'd prefer not to go down a shader route as I haven't taught myself this area yet so unless I have too I'd rather try to achieve this with simple alpha blending. Happy to use a shader approach. Cheers. Additional These third images are obviously light sources being cast onto the first image showing the specular information from the second image to simulate the light 'shining' off the objects in the first image. The solution I implement will need to allow two light sources to potentially overlap so my current thoughts are that the alpha values of the two images will need to be combined (Added?) to produce a final image which masks the second image? Don't worry about things like coloured lights. For this technique the lights are all considered white.

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  • Looping 3D environment in shmups

    - by kamziro
    So I was watching Ikaruga: http://www.youtube.com/watch?v=Aj23K8Ri68E And then raystorm: http://www.youtube.com/watch?v=TQ4V0G5ykAg After looking at their 3D backgrounds for a little bit, it appears that they use a lot of repeated segments. How would one start with the development with such systems? Would there be editors that can be used (or at least help) with creating the environments? Perhaps a 3D map with splines describing the path of the ship, as well as events on the splines?

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  • Surface normal to screen angle

    - by Tannz0rz
    I've been struggling to get this working. I simply wish to take a surface normal and convert it to a screen angle. As an example, assuming we're working with the highlighted surface on the sphere below, where the arrow is the normal, the 2D angle would obviously be PI/4 radians. Here's one of the many things I've tried to no avail: float4 A = v.vertex; float4 B = v.vertex + float4(v.normal, 0.0); A = mul(VP, A); B = mul(VP, B); A.xy = (0.5 * (A.xy / A.w)) + 0.5; B.xy = (0.5 * (B.xy / B.w)) + 0.5; o.theta = atan2(B.y - A.y, B.x - A.x); I'm finally at my wit's end. Thanks for any and all help.

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  • Child transforms problem when loading 3DS models using assimp

    - by MhdSyrwan
    I'm trying to load a textured 3d model into my scene using assimp model loader. The problem is that child meshes are not situated correctly (they don't have the correct transformations). In brief: all the mTansform matrices are identity matrices, why would that be? I'm using this code to render the model: void recursive_render (const struct aiScene *sc, const struct aiNode* nd, float scale) { unsigned int i; unsigned int n=0, t; aiMatrix4x4 m = nd->mTransformation; m.Scaling(aiVector3D(scale, scale, scale), m); // update transform m.Transpose(); glPushMatrix(); glMultMatrixf((float*)&m); // draw all meshes assigned to this node for (; n < nd->mNumMeshes; ++n) { const struct aiMesh* mesh = scene->mMeshes[nd->mMeshes[n]]; apply_material(sc->mMaterials[mesh->mMaterialIndex]); if (mesh->HasBones()){ printf("model has bones"); abort(); } if(mesh->mNormals == NULL) { glDisable(GL_LIGHTING); } else { glEnable(GL_LIGHTING); } if(mesh->mColors[0] != NULL) { glEnable(GL_COLOR_MATERIAL); } else { glDisable(GL_COLOR_MATERIAL); } for (t = 0; t < mesh->mNumFaces; ++t) { const struct aiFace* face = &mesh->mFaces[t]; GLenum face_mode; switch(face->mNumIndices) { case 1: face_mode = GL_POINTS; break; case 2: face_mode = GL_LINES; break; case 3: face_mode = GL_TRIANGLES; break; default: face_mode = GL_POLYGON; break; } glBegin(face_mode); for(i = 0; i < face->mNumIndices; i++)// go through all vertices in face { int vertexIndex = face->mIndices[i];// get group index for current index if(mesh->mColors[0] != NULL) Color4f(&mesh->mColors[0][vertexIndex]); if(mesh->mNormals != NULL) if(mesh->HasTextureCoords(0))//HasTextureCoords(texture_coordinates_set) { glTexCoord2f(mesh->mTextureCoords[0][vertexIndex].x, 1 - mesh->mTextureCoords[0][vertexIndex].y); //mTextureCoords[channel][vertex] } glNormal3fv(&mesh->mNormals[vertexIndex].x); glVertex3fv(&mesh->mVertices[vertexIndex].x); } glEnd(); } } // draw all children for (n = 0; n < nd->mNumChildren; ++n) { recursive_render(sc, nd->mChildren[n], scale); } glPopMatrix(); } What's the problem in my code ? I've added some code to abort the program if there's any bone in the meshes, but the program doesn't abort, this means : no bones, is that normal? if (mesh->HasBones()){ printf("model has bones"); abort(); } Note: I am using openGL & SFML & assimp

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  • Is 2 lines of push/pop code for each pre-draw-state too many?

    - by Griffin
    I'm trying to simplify vector graphics management in XNA; currently by incorporating state preservation. 2X lines of push/pop code for X states feels like too many, and it just feels wrong to have 2 lines of code that look identical except for one being push() and the other being pop(). The goal is to eradicate this repetitiveness,and I hoped to do so by creating an interface in which a client can give class/struct refs in which he wants restored after the rendering calls. Also note that many beginner-programmers will be using this, so forcing lambda expressions or other advanced C# features to be used in client code is not a good idea. I attempted to accomplish my goal by using Daniel Earwicker's Ptr class: public class Ptr<T> { Func<T> getter; Action<T> setter; public Ptr(Func<T> g, Action<T> s) { getter = g; setter = s; } public T Deref { get { return getter(); } set { setter(value); } } } an extension method: //doesn't work for structs since this is just syntatic sugar public static Ptr<T> GetPtr <T> (this T obj) { return new Ptr<T>( ()=> obj, v=> obj=v ); } and a Push Function: //returns a Pop Action for later calling public static Action Push <T> (ref T structure) where T: struct { T pushedValue = structure; //copies the struct data Ptr<T> p = structure.GetPtr(); return new Action( ()=> {p.Deref = pushedValue;} ); } However this doesn't work as stated in the code. How might I accomplish my goal? Example of code to be refactored: protected override void RenderLocally (GraphicsDevice device) { if (!(bool)isCompiled) {Compile();} //TODO: make sure state settings don't implicitly delete any buffers/resources RasterizerState oldRasterState = device.RasterizerState; DepthFormat oldFormat = device.PresentationParameters.DepthStencilFormat; DepthStencilState oldBufferState = device.DepthStencilState; { //Rendering code } device.RasterizerState = oldRasterState; device.DepthStencilState = oldBufferState; device.PresentationParameters.DepthStencilFormat = oldFormat; }

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  • 2D Rectangle Collision Response with Multiple Rectangles

    - by Justin Skiles
    Similar to: Collision rectangle response I have a level made up of tiles where the edges of the level are made up of collidable rectangles. The player's collision box is represented by a rectangle as well. The player can move in 8 directions. The player's velocity is equal in X and Y directions and constant. Each update, I am checking the player's collision against all tiles that are a certain distance away. When the player collides with a rectangle, I am finding the intersection depth and resolving along the most shallow axis followed by the other axis. This resolution happens for both axes simultaneously. See below for two examples of situations where I am having trouble. Moving up-left against the left wall In the scenario below, the player is colliding with two tiles. The tile intersection depth is equal on both axes for the top tile and more shallow in the X axis for the middle tile. Because the player is moving up the wall, the player should slide in an upward direction along the wall. This works properly as long as the rectangle with the more shallow depth is evaluated first. If the equal intersection depth rectangle is evaluated first, there is a chance the player becomes stuck. Moving up-left against the top wall Here is an identical scenario with the exception that the collision is with the top wall. The same problem occurs at the corners when intersection depth is equal for both axes. I guess my overall question is: How can I ensure that collision response occurs on tiles that have non-equal intersection depth before tiles that have equal intersection depth in order to get around the weirdness that occurs at these corners. Sean's answer in the linked question was good, but his solution required having different velocity components in a certain direction. My situation has equal velocities, so there's no good way to tell which direction to resolve at corners. I hope I have made my explanation clear.

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  • Simple project - make a 3D box tumble and fall to the ground [closed]

    - by Dominic Bou-Samra
    Possible Duplicate: Resources to learn programming rigid body simulation Hi guys, I want to try learning rigid-body dynamic simulation. I have done a fluid and cloth simulation before, but never anything rigid. My maths knowledge is limited in that I don't know the notation that well. Are there any good cliff-notes, tutorials, guides on how I would accomplish a simple task like this? I don't want a super complex pdf that's only a little relevant. Thanks.

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  • Who should map physical keys to abstract keys?

    - by Paul Manta
    How do you bridge the gap between the library's low-level event system and your engine's high-level event system? (I'm not necessarily talking about key events, but also about quit events.) At the top level of my event system, I send out KeyPressedEvents, KeyRelesedEvents and others of this kind. These high-level events only contain the abstract values of the keys (they don't say that Space way pressed, but that the JumpKey was pressed, for example). Whose responsibility should it be to map the "JumpKey" to an actual key on the keyboard?

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  • Checking whether a specific key was pressed in enchantJS

    - by MxyL
    I am using enchantJS and would like to use the letters and numbers as well as numpad on a keyboard to do different things (eg: hotkeys). From this page http://users.csc.calpoly.edu/~foaad/enchant/guide/playerInput.html By default, enchant.js provides input listeners for six buttons: UP, DOWN, LEFT, RIGHT, A, and B. By default, the directions are bound to the arrow keys. Any of the six buttons may also be bound to any key with an ASCII value. We’ll address that later. So enchant provides the ability to bind keys to different input such as up, down, left, right...but how can I simply check whether the D or X key was pressed, and if so, perform certain actions based on that event?

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  • Inverse projection: question about w coordinate

    - by fayeWilly
    I have to perform in shader an inverse projection from a u/v of a render target. What I do is: Get NDC as 2*(u,v,depth) - 1 Then world space as tmp = (P*V)^-1 * (NDC,1.0); world space = tmp/tmp.w; This apparently works, but I am confused about the w division there. Why this work? Shouldn't be a multiplication by a w somewhere (as in the "forward" pipeline there is the perpsective division?) Thank you, Faye

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  • Managing constant buffers without FX interface

    - by xcrypt
    I am aware that there is a sample on working without FX in the samplebrowser, and I already checked that one. However, some questions arise: In the sample: D3DXMATRIXA16 mWorldViewProj; D3DXMATRIXA16 mWorld; D3DXMATRIXA16 mView; D3DXMATRIXA16 mProj; mWorld = g_World; mView = g_View; mProj = g_Projection; mWorldViewProj = mWorld * mView * mProj; VS_CONSTANT_BUFFER* pConstData; g_pConstantBuffer10->Map( D3D10_MAP_WRITE_DISCARD, NULL, ( void** )&pConstData ); pConstData->mWorldViewProj = mWorldViewProj; pConstData->fTime = fBoundedTime; g_pConstantBuffer10->Unmap(); They are copying their D3DXMATRIX'es to D3DXMATRIXA16. Checked on msdn, these new matrices are 16 byte aligned and optimised for intel pentium 4. So as my first question: 1) Is it necessary to copy matrices to D3DXMATRIXA16 before sending them to the constant buffer? And if no, why don't we just use D3DXMATRIXA16 all the time? I have another question about managing multiple constant buffers within one shader. Suppose that, within your shader, you have multiple constant buffers that need to be updated at different times: cbuffer cbNeverChanges { matrix View; }; cbuffer cbChangeOnResize { matrix Projection; }; cbuffer cbChangesEveryFrame { matrix World; float4 vMeshColor; }; Then how would I set these buffers all at different times? g_pd3dDevice->VSSetConstantBuffers( 0, 1, &g_pConstantBuffer10 ); gives me the possibility to set multiple buffers, but that is within one call. 2) Is that okay even if my constant buffers are updated at different times? And do I suppose I have to make sure the constantbuffers are in the same position in the array as the order they appear in the shader?

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  • Is good practice to optimize FPS even when it's above the lower limit to give illusion of movement?

    - by rraallvv
    I started over 50 FPS on the iPhone, but now I'm bellow 30 PFS, I've seen most iPhone games clamped to either 60 or 30 FPS, even when 24 or less would give the illusion of movement. I've concidered my limit to be a little bit over 15 FPS, in fact my physics simulation is updated at that rate (15.84 steps/s) as that is the lowest that still give fluid movement, a bit lower gives jerky motion. Is there a practical reason why to clamp FPS way above the lower limit? Update: The following image could help to clarify I can independently set the physic simulation step, frame rate, and simulation interval update. My concern is why should I clamp any of those to values greater than the minimum? For instance to conserve battery life I could just to choose the lower limits, but it seems that 60 or 30 FPS are the most used values.

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  • Scaling along an arbitrary axis (Dealing with non-uniform scale)

    - by Jon
    I'm trying to build my own little engine to get more familiar with the concepts of 3D programming. I have a transform class that on each frame it creates a Scaling Matrix (S), a Rotation Matrix from a Quaternion (R) and concatenates them together (S*R). Once i have SR, I insert the translation values into the bottom of the three columns. So i end up with a transformation matrix that looks like: [SR SR SR 0] [SR SR SR 0] [SR SR SR 0] [tx ty tz 1] This works perfectly in all cases except when rotating an object that has a non-uniform scale. For example a unit cube with ScaleX = 4, ScaleY = 2, ScaleZ = 1 will give me a rectangular box that is 4 times as wide as the depth and twice as high as the depth. If i then translate this around, the box stays the same and looks normal. The problem happens whenever I try to rotate this scaled box. The shape itself becomes distorted and it appears as though the Scale factors are affecting the object on the World X,Y,Z axis rather than the local X,Y,Z axis of the object. I've done some pretty extensive research through a variety of textbooks (Eberly, Moller/Hoffman, Phar etc) and there isn't a ton there to go off of. Online, most of the answers say to avoid non-uniform scaling which I understand the desire to avoid it, but I'd still like to figure out how to support it. The only thing I can think off is that when constructing a Scale Matrix: [sx 0 0 0] [0 sy 0 0] [0 0 sz 0] [0 0 0 1] This is scaling along the World Axis instead of the object's local Direction, Up and Right vectors or it's local Z, Y, X axis. Does anyone have any tips or ideas on how to handle construction a transformation matrix that allows for non-uniform scaling and rotation? Thanks!

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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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