Search Results

Search found 12087 results on 484 pages for 'game mechanics'.

Page 327/484 | < Previous Page | 323 324 325 326 327 328 329 330 331 332 333 334  | Next Page >

  • Shader compile log depending on hardware

    - by dreta
    I'm done with the core of my graphics engine and I'm testing it on every platform I can get my hands on. Now, what I noticed is that different drivers return different shader and program compile log content. For example, on my friend's laptop if you successfuly compile a shader then the log is simply empty. However on my PC I get some useful information along with it. So if I compile a vertex shader, I'll get: Vertex shader was successfully compiled to run on hardware. Which isn't that impressive, but is what happens when I compile a program. On my friend's computer the log is empty, since the program compiles. However on my own computer I get: Vertex shader(s) linked, fragment shader(s) linked. Which is awesome, because I'm attaching a geometry shader with 0 (I have a geometry shader file with trash, so it doesn't compile and the pointer is set to 0), and the compiler just tells me which shaders linked. Now it got me thinking, if I was going to buy a graphics card, is there a way for me to get the information about whether or not I'll get this "extended" compile information? Maybe it's vendor specific? Now I don't expect an answer TBH, this seems a bit obscure, but maybe somebody has any experience with this and could post it.

    Read the article

  • Restrict movement within a radius

    - by Phil
    I asked a similar question recently but now I think I know more about what I really want to know. I can answer my own question if I get to understand this bit. I have a situation where a sprite's center point needs to be constrained within a certain boundary in 2d space. The boundary is circular so the sprite is constrained within a radius. This radius is defined as a distance from the center of a certain point. I know the position of the center point and I can track the center position of the sprite. This is the code to detect the distance: float distance = Vector2.Distance(centerPosition, spritePosition)); if (distance > allowedDistance) { } The positions can be wherever on the grid, they are not described as in between -1 or 1. So basically the detecting code works, it only prints when the sprite is outside of it's boundary I just don't know what to do when it oversteps. Please explain any math used as I really want to understand what you're thinking to be able to elaborate on it myself.

    Read the article

  • IDirect3DDevice9::GetRenderTargetData() returns no data

    - by P. Avery
    I've got a simple function to get the rendertarget data of an RT( w/default pool ). This particular RT has a resolution of 1x1( it's the 10'th and final mip of a texture ). Here is my code to get data for IDirect3DSurface9 *pTargetSurface: IDirect3DSurface9 *pSOS = NULL; pd3dDevice->CreateOffScreenPlainSurface( 1, 1, D3DFMT_A8R8G8B8, D3DPOOL_SYSTEMMEM, &pSOS, NULL ); // get residual energy if( FAILED( hr = pd3dDevice->GetRenderTargetData( pTargetSurface, pSOS ) ) ) { DebugStringDX( ClassName, "Failed to IDirect3DDevice9::GetRenderTargetData() at DownsampleArea()", __LINE__, hr ); goto Exit; } // lock surface if( FAILED( hr = pSOS->LockRect( &rct, NULL, D3DLOCK_READONLY ) ) ) { DebugStringDX( ClassName, "Failed to IDirect3DSurface9::LockRect() at DownsampleArea()", __LINE__, hr ); goto Exit; } // get residual energy from downsampled texture pByte = ( BYTE* )rct.pBits; D3DXVECTOR4 vEnergy; vEnergy.z = ( float )pByte[ 0 ] / 255.0f; vEnergy.y = ( float )pByte[ 1 ] / 255.0f; vEnergy.x = ( float )pByte[ 2 ] / 255.0f; vEnergy.w = ( float )pByte[ 3 ] / 255.0f; V( pSOS->UnlockRect() ); All formatting and settings are correct, directx in debug mode shows no errors... The problem is that the 4 bytes above are 0...I know this to be incorrect by using PIX to debug...PIX shows that RGB bytes are 0.078 and Alpah is 1. These values are not less than that which can be represented by a single byte( 1 / 255 ). Any ideas? Am I copying rendertarget data correctly?

    Read the article

  • Having trouble's understanding NIF model file format?

    - by NoobScratcher
    I'm attempting too develop a 3rd party application to make it easy to import 3d model part's into my mod for skyrim the plan was to have a fileviewer and preview window of the nif model but since , I don't know what the NIF file format actually is or where to get the vertex data from it or the hole nine yards of parsing a text file in detail I'm at a lost what to do. I'm very good at C++ but not at this super over complicated file formats , id much prefer .obj over the nif file format specification here -- http://niftools.sourceforge.net/doc/nif/index.html If someone could help me in understanding the file format in a natural and simple way and the exact parsing needed to create the 3D Model in the frustum and a explanation on how you figured that out would be happy to know. I use cygwin , notepad++ , win32 7

    Read the article

  • What is the standard technique for shifting the frames of a sprite according to user input?

    - by virtual__
    From my own experience, I developed two techniques for changing the sprites of a character that's reacting to user input -- this in the context of a classic 2D platformer. The first one is to store all character's pixmaps in a list, putting the index of the currently used pixmap in an ordinary variable. This way, every time the player presses a key -- say the right arrow for moving the character forward -- the graphics engine sees what's the next pixmap to draw, draws it, and increments the index counter. That's a pretty common approach I believe, the problem is that in this case the animation's quality depends not only on the number of sprites available but also on how often your engine listens to user input. The second technique is to actually play an animation every key press event. For this you can use any sort of animation framework you want. It's only necessary to set the timer, the animation steps and to call the animation's play() method on your key press event handler. The problem with that approach is that is lacks responsiveness, since the character won't react to any input while the current animation is still being played. What I want to know is whether you are using one of these techniques -- or something similar -- in your games, or whether there's a standard method for animating sprites out there that's widely known by everybody but me.

    Read the article

  • Common way to store model transformations

    - by redreggae
    I ask myself what's the best way to store the transformations in a model class. What I came up with is to store the translation and scaling in a Vector3 and the rotation in a Matrix4. On each update (frame) I multiply the 3 matrices (first build a Translation and Scaling Matrix) to get the world matrix. In this way I have no accumulated error. world = translation * scaling * rotation Another way would be to store the rotation in a quaternion but then I would have a high cost to convert to a matrix every time step. If I lerp the model I convert the rotation matrix to quaternion and then back to matrix. For speed optimization I have a dirty flag for each transformation so that I only do a matrix multiplication if necessary. world = translation if (isScaled) { world *= scaling } if (isRotated) { world *= rotation } Is this a common way or is it more common to have only one Matrix4 for all transformations? And is it better to store the rotation only as quaternion? For info: Currently I'm building a CSS3D engine in Javascript but these questions are relevant for every 3D engine.

    Read the article

  • Calculate initial velocity of a 3d vector-based projectile

    - by Frotty
    Okay, so I got a Projectile with 2 Vectors, position and velocity. I now want to calculate the initial velocity for it in order to reach a specific point on the map. Or actually, how high has the start z-velocity to be (because x and y are probably defined by a speed variable) in order for the projectile to hit the marked position. The projectile is influenced by a constant gravity vector. All calculations are done 32 times per second. I want this, because I don't want to use a parabola function, so the projectile can still be influenced by other sources, simply adding some velocity. I didn't really find anything referring to that topic and would be glad for every helping answer, Thanks.

    Read the article

  • Particles are not moving correctly [closed]

    - by cr33p
    I want to make a particle explosion, after something gets destroyed, but somehow only one line of mixed colors show up on the screen. Here's the header: http://pastebin.com/JW5bPLj2 Here's the source: http://pastebin.com/KHmFqytD I don't get what's wrong, as it's nearly the same as in "Programming Linux Games" Can somebody help me fix that? PS: "Uint32 delta" is needed to update the pixels based on time. PSS: Maybe I should add that it's programmed in C and includes SDL. EDIT: Found the problem. It was the "drawParticles" function. The problem was, that I passed a double to "offset" (as particles[i].x, etc are all doubles). So I ended up with values like ~MAX_INT because I didn't cast the doubles properly to ints.

    Read the article

  • What are some ways of making manageable complex AI?

    - by Tetrad
    In the past I've used simple systems like finite state machines (FSMs) or hierarchical FSMs to control AI behavior. For any complex system, this pattern falls apart very quickly. I've heard about behavior trees and it seems like that's the next obvious step, but haven't seen a working implementation or really tried going down that route yet. Are there any other patterns to making manageable yet complex AI behaviors?

    Read the article

  • Making efficeint voxel engines using "chunks"

    - by Wardy
    Concept I'm currently looking in to how voxel engines work with a view to possibly making one myself. I see a lot of stuff like this ... https://sites.google.com/site/letsmakeavoxelengine/home/chunks ... which talks about how to go about reducing the draw calls. What I can't seem to understand is how it actually saves draw call counts on the basis of the logic being something like this ... Without chunks foreach voxel in myvoxels DrawIfVisible() With Chunks foreach chunk in mychunks DrawIfVisible() which then does ... foreach voxel in myvoxels DrawIfVisible() So surely you saved nothing ?!?! You still make a draw call for each visible voxel do you not? A visible voxel needs a draw call in either scenario. The only real saving I can see is that the logic that evaluates a chunk will be able to determine if a large number of voxels are visible or not effectively saving a bit of "is this chunk visible" cpu time. But it's the draw calls that interest me ... The fewer of those, the faster the application. EDIT: In case it makes any difference I will probably be using XNA (DX not OpenGL) for my engine so don't consider my choice of example in the link above my choice of technology. But this question is such that I doubt it would matter.

    Read the article

  • Blender 2.6: How to Merge the Pros of Meshes and Surfaces

    - by fridojet
    there are two interesting kinds of objects: Meshes and Surfaces. Each of them offers very cool features. Object Type Specific Features Nice Features of Surfaces: (for example) They're as scalable as vector graphics (really nice!) You can build winding things real simply. Nice Features of Meshes: (for example) You can build organic things really good using the Sculpt Mode and a graphic tablet. You can use some special things like Physics. My Question There are things for which Surfaces are better and things for which Meshes are better. But how can I use both the best features of Surfaces and the best features of Meshes on one object at once? For example: How can I use Physics (like on Meshes) on lossless scalable objects (like Surfaces)? Thanks.

    Read the article

  • AndEngine player, background and camera

    - by valdemar593
    I'm developing a 2D shooter using AndEngine. At the moment I'm trying to make the camera follow the player. As I've understood the common approach is to use the SmoothCamera zooming it and setting the chased entity. The problem is that the camera follows the player WITH background moving also (RepeatingSpriteBackground), so it looks like the player doesn't move at all though the actual position changes. So I don't really get how to make the camera follow the player and have the background not moving. Thanks in advance.

    Read the article

  • XNA Octree with batching

    - by Alex
    I'm integrating batching in my engine. However I'm using an octree which is auto generated around my scene. Now batching renders a hole group at ones while an octree sorts out which objects that should be rendered within the camera frustum, therefore dividing the group. Batching and octree doesn't go along very well, right? Problem: The way I see it I have two options, either create batch groups based on objects who are close to one another within the octree or I can rebuild the batching matrixbuffer for the instances visible each frame. Which approach should I go with or does there exist another solution?

    Read the article

  • 2-components color model

    - by Cyan
    RGB is the natural color model for OpenGL. But a lot of other color models exist. For example, CMY(K) for printers, YUV for JPEG, the little cousins YCbCr and YCoCg, HSL & HSV from the 70's, and so on. All these models tend to share a common property : they are based on 3 components. Therefore my question is : Does it exist a 2-components color model ? I'm surprised to not find any. I was expecting something along the line of Hue+light could exist. I guess it cannot be as "complete" as a true 3-components color model, but a fine-enough approximation will be good for my usecase. The end objective is to store the 2 components into a single BC5 texture (GL_COMPRESSED_RED_GREEN_RGTC2 in OpenGL). The 3rd component requires a second fetch into a second texture, which hurts performance.

    Read the article

  • How to texture voxel terrain without triplanar texturing?

    - by Thelvyn
    How can a voxel terrain (marching cubes) be textured without triplanar mapping ? The goal being to have more artistic freedom. I think, I could unwrap the mesh while extracting the isosurface then use projective painting. But I do not know how to handle terrain modifications without breaking the texture. I also guess that virtual texturing could help here. Links for these matters would be appreciated.

    Read the article

  • How can I render multiple windows with DirectX 9 in C++?

    - by Friso1990
    I'm trying to render multiple windows, using DirectX 9 and swap chains, but even though I create 2 windows, I only see the first one that I've created. My RendererDX9 header is this: #include <d3d9.h> #include <Windows.h> #include <vector> #include "RAT_Renderer.h" namespace RAT_ENGINE { class RAT_RendererDX9 : public RAT_Renderer { public: RAT_RendererDX9(); ~RAT_RendererDX9(); void Init(RAT_WindowManager* argWMan); void CleanUp(); void ShowWin(); private: LPDIRECT3D9 renderInterface; // Used to create the D3DDevice LPDIRECT3DDEVICE9 renderDevice; // Our rendering device LPDIRECT3DSWAPCHAIN9* swapChain; // Swapchain to make multi-window rendering possible WNDCLASSEX wc; std::vector<HWND> hwindows; void Render(int argI); }; } And my .cpp file is this: #include "RAT_RendererDX9.h" static LRESULT CALLBACK MsgProc( HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam ); namespace RAT_ENGINE { RAT_RendererDX9::RAT_RendererDX9() : renderInterface(NULL), renderDevice(NULL) { } RAT_RendererDX9::~RAT_RendererDX9() { } void RAT_RendererDX9::Init(RAT_WindowManager* argWMan) { wMan = argWMan; // Register the window class WNDCLASSEX windowClass = { sizeof( WNDCLASSEX ), CS_CLASSDC, MsgProc, 0, 0, GetModuleHandle( NULL ), NULL, NULL, NULL, NULL, "foo", NULL }; wc = windowClass; RegisterClassEx( &wc ); for (int i = 0; i< wMan->getWindows().size(); ++i) { HWND hWnd = CreateWindow( "foo", argWMan->getWindow(i)->getName().c_str(), WS_OVERLAPPEDWINDOW, argWMan->getWindow(i)->getX(), argWMan->getWindow(i)->getY(), argWMan->getWindow(i)->getWidth(), argWMan->getWindow(i)->getHeight(), NULL, NULL, wc.hInstance, NULL ); hwindows.push_back(hWnd); } // Create the D3D object, which is needed to create the D3DDevice. renderInterface = (LPDIRECT3D9)Direct3DCreate9( D3D_SDK_VERSION ); // Set up the structure used to create the D3DDevice. Most parameters are // zeroed out. We set Windowed to TRUE, since we want to do D3D in a // window, and then set the SwapEffect to "discard", which is the most // efficient method of presenting the back buffer to the display. And // we request a back buffer format that matches the current desktop display // format. D3DPRESENT_PARAMETERS deviceConfig; ZeroMemory( &deviceConfig, sizeof( deviceConfig ) ); deviceConfig.Windowed = TRUE; deviceConfig.SwapEffect = D3DSWAPEFFECT_DISCARD; deviceConfig.BackBufferFormat = D3DFMT_UNKNOWN; deviceConfig.BackBufferHeight = 1024; deviceConfig.BackBufferWidth = 768; deviceConfig.EnableAutoDepthStencil = TRUE; deviceConfig.AutoDepthStencilFormat = D3DFMT_D16; // Create the Direct3D device. Here we are using the default adapter (most // systems only have one, unless they have multiple graphics hardware cards // installed) and requesting the HAL (which is saying we want the hardware // device rather than a software one). Software vertex processing is // specified since we know it will work on all cards. On cards that support // hardware vertex processing, though, we would see a big performance gain // by specifying hardware vertex processing. renderInterface->CreateDevice( D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hwindows[0], D3DCREATE_SOFTWARE_VERTEXPROCESSING, &deviceConfig, &renderDevice ); this->swapChain = new LPDIRECT3DSWAPCHAIN9[wMan->getWindows().size()]; this->renderDevice->GetSwapChain(0, &swapChain[0]); for (int i = 0; i < wMan->getWindows().size(); ++i) { renderDevice->CreateAdditionalSwapChain(&deviceConfig, &swapChain[i]); } renderDevice->SetRenderState(D3DRS_CULLMODE, D3DCULL_CCW); // Set cullmode to counterclockwise culling to save resources renderDevice->SetRenderState(D3DRS_AMBIENT, 0xffffffff); // Turn on ambient lighting renderDevice->SetRenderState(D3DRS_ZENABLE, TRUE); // Turn on the zbuffer } void RAT_RendererDX9::CleanUp() { renderDevice->Release(); renderInterface->Release(); } void RAT_RendererDX9::Render(int argI) { // Clear the backbuffer to a blue color renderDevice->Clear( 0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB( 0, 0, 255 ), 1.0f, 0 ); LPDIRECT3DSURFACE9 backBuffer = NULL; // Set draw target this->swapChain[argI]->GetBackBuffer(0, D3DBACKBUFFER_TYPE_MONO, &backBuffer); this->renderDevice->SetRenderTarget(0, backBuffer); // Begin the scene renderDevice->BeginScene(); // End the scene renderDevice->EndScene(); swapChain[argI]->Present(NULL, NULL, hwindows[argI], NULL, 0); } void RAT_RendererDX9::ShowWin() { for (int i = 0; i < wMan->getWindows().size(); ++i) { ShowWindow( hwindows[i], SW_SHOWDEFAULT ); UpdateWindow( hwindows[i] ); // Enter the message loop MSG msg; while( GetMessage( &msg, NULL, 0, 0 ) ) { if (PeekMessage( &msg, NULL, 0U, 0U, PM_REMOVE ) ) { TranslateMessage( &msg ); DispatchMessage( &msg ); } else { Render(i); } } } } } LRESULT CALLBACK MsgProc( HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam ) { switch( msg ) { case WM_DESTROY: //CleanUp(); PostQuitMessage( 0 ); return 0; case WM_PAINT: //Render(); ValidateRect( hWnd, NULL ); return 0; } return DefWindowProc( hWnd, msg, wParam, lParam ); } I've made a sample function to make multiple windows: void RunSample1() { //Create the window manager. RAT_ENGINE::RAT_WindowManager* wMan = new RAT_ENGINE::RAT_WindowManager(); //Create the render manager. RAT_ENGINE::RAT_RenderManager* rMan = new RAT_ENGINE::RAT_RenderManager(); //Create a window. //This is currently needed to initialize the render manager and create a renderer. wMan->CreateRATWindow("Sample 1 - 1", 10, 20, 640, 480); wMan->CreateRATWindow("Sample 1 - 2", 150, 100, 480, 640); //Initialize the render manager. rMan->Init(wMan); //Show the window. rMan->getRenderer()->ShowWin(); } How do I get the multiple windows to work?

    Read the article

  • Android Dynamic 2D Map

    - by Deltharis
    My problem is, I want to create a 2D tiled map. Yes, I know it's been asked a lot. I've seen answers that propose the use of tiled however it only allows (or so it seems to me) to generate static maps that do not change once generated. And I need a large empty uniform space of empty tiles, upon which players may place various buildings (some spanning more than one tile and logically being the same one). How to approach this in Android? Do I make some kind of TableLayout, use arbitrarly large amount of rows and imageviews (with my emptyTile), than somehow work event-based changing of image ids from there? I'd think that only a portion of that map should be visible at a time, but I don't see how scrolling around could be the part of that structure.

    Read the article

  • How to configure background image to be at the bottom OpenGL Android

    - by Maxim Shoustin
    I have class that draws white line: public class Line { //private FloatBuffer vertexBuffer; private FloatBuffer frameVertices; ByteBuffer diagIndices; float[] vertices = { -0.5f, -0.5f, 0.0f, -0.5f, 0.5f, 0.0f }; public Line(GL10 gl) { // a float has 4 bytes so we allocate for each coordinate 4 bytes ByteBuffer vertexByteBuffer = ByteBuffer.allocateDirect(vertices.length * 4); vertexByteBuffer.order(ByteOrder.nativeOrder()); // allocates the memory from the byte buffer frameVertices = vertexByteBuffer.asFloatBuffer(); // fill the vertexBuffer with the vertices frameVertices.put(vertices); // set the cursor position to the beginning of the buffer frameVertices.position(0); } /** The draw method for the triangle with the GL context */ public void draw(GL10 gl) { gl.glEnableClientState(GL10.GL_VERTEX_ARRAY); gl.glVertexPointer(2, GL10.GL_FLOAT, 0, frameVertices); gl.glColor4f(1.0f, 1.0f, 1.0f, 1f); gl.glDrawArrays(GL10.GL_LINE_LOOP , 0, vertices.length / 3); gl.glLineWidth(5.0f); gl.glDisableClientState(GL10.GL_VERTEX_ARRAY); } } It works fine. The problem is: When I add BG image, I don't see the line glView = new GLSurfaceView(this); // Allocate a GLSurfaceView glView.setEGLConfigChooser(8, 8, 8, 8, 16, 0); glView.setRenderer(new mainRenderer(this)); // Use a custom renderer glView.setBackgroundResource(R.drawable.bg_day); // <- BG glView.setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY); glView.getHolder().setFormat(PixelFormat.TRANSLUCENT); How to get rid of that?

    Read the article

  • Randomly spawning bitmaps on cnvas

    - by Toystoj
    I need some ideas in order to finish algorithm. I'm randomly placing objects (bitmaps) on canvas without overlapping. Time needed to finish it is my problem. When I need to spawn for example 80% of canvas it takes to long. So i was thinking : I should make some change when the bitmaps take off 50 % of canvas. I want to tell algorithm that it should generate new locations (x,y) where it is free space. My question is : How to render new location (x,y) in place where is free space. In summary: Things I know : object location (x,y) 4 corners (x,y) of object object width, height canvas width, height Any suggestions?

    Read the article

  • Sprite animation problem

    - by hustlerinc
    I have this sprite I have to animate. The sprite is 7 images total but animation is 10 frames (2 positions are repeated). The order I want to go through the frames is like this: 3 - 4 - 5 - 6 - 4 - 3 - 2 - 1 - 0 - 2. My problem is how can I skip 1 frame once I reach the end of each direction? The reason I want to skip is to save me from creating duplicate positions in the spritesheet. I'm doing this in Javascript.

    Read the article

  • In 3D camera math, calculate what Z depth is pixel unity for a given FOV

    - by badweasel
    I am working in iOS and OpenGL ES 2.0. Through trial and error I've figured out a frustum to where at a specific z depth pixels drawn are 1 to 1 with my source textures. So 1 pixel in my texture is 1 pixel on the screen. For 2d games this is good. Of course it means that I also factor in things like the size of the quad and the size of the texture. For example if my sprite is a quad 32x32 pixels. The quad size is 3.2 units wide and tall. And the texcoords are 32 / the size of the texture wide and tall. Then the frustum is: matrixFrustum(-(float)backingWidth/frustumScale,(float)backingWidth/frustumScale, -(float)backingHeight/frustumScale, (float)backingHeight/frustumScale, 40, 1000, mProjection); Where frustumScale is 800 for a retina screen. Then at a distance of 800 from camera the sprite is pixel for pixel the same as photoshop. For 3d games sometimes I still want to be able to do this. But depending on the scene I sometimes need the FOV to be different things. I'm looking for a way to figure out what Z depth will achieve this same pixel unity for a given FOV. For this my mProjection is set using: matrixPerspective(cameraFOV, near, far, (float)backingWidth / (float)backingHeight, mProjection); With testing I found that at an FOV of 45.0 a Z of 38.5 is very close to pixel unity. And at an FOV of 30.0 a Z of 59.5 is about right. But how can I calculate a value that is spot on? Here's my matrixPerspecitve code: void matrixPerspective(float angle, float near, float far, float aspect, mat4 m) { //float size = near * tanf(angle / 360.0 * M_PI); float size = near * tanf(degreesToRadians(angle) / 2.0); float left = -size, right = size, bottom = -size / aspect, top = size / aspect; // Unused values in perspective formula. m[1] = m[2] = m[3] = m[4] = 0; m[6] = m[7] = m[12] = m[13] = m[15] = 0; // Perspective formula. m[0] = 2 * near / (right - left); m[5] = 2 * near / (top - bottom); m[8] = (right + left) / (right - left); m[9] = (top + bottom) / (top - bottom); m[10] = -(far + near) / (far - near); m[11] = -1; m[14] = -(2 * far * near) / (far - near); } And my mView is set using: lookAtMatrix(cameraPos, camLookAt, camUpVector, mView); * UPDATE * I'm going to leave this here in case anyone has a different solution, can explain how they do it, or why this works. This is what I figured out. In my system I use a 10th scale unit to pixels on non-retina displays and a 20th scale on retina displays. The iPhone is 640 pixels wide on retina and 320 pixels wide on non-retina (obsolete). So if I want something to be the full screen width I divide by 20 to get the OpenGL unit width. Then divide that by 2 to get the left and right unit position. Something 32 units wide centered on the screen goes from -16 to +16. Believe it or not I have an excel spreadsheet do all this math for me and output all the vertex data for my sprite sheet. It's an arbitrary thing I made up to do .1 units = 1 non-retina pixel or 2 retina pixels. I could have made it .01 units = 2 pixels and someday I might switch to that. But for now it's the other. So the width of the screen in units is 32.0, and that means the left most pixel is at -16.0 and the right most is at 16.0. After messing a bit I figured out that if I take the [0] value of an identity modelViewProjection matrix and multiply it by 16 I get the depth required to get 1:1 pixels. I don't know why. I don't know if the 16 is related to the screen size or just a lucky guess. But I did a test where I placed a sprite at that calculated depth and varied the FOV through all the valid values and the object stays steady on screen with 1:1 pixels. So now I'm just calculating the unityDepth that way. If someone gives me a better answer I'll checkmark it.

    Read the article

  • glTexImage2D not loading my data

    - by Clyde
    Can anyone suggest why this code doesn't work? When I draw using this texture all I get is black. If I use GLUtils.texImage2D() to load a png file, it works correctly. ByteBuffer bb = ByteBuffer.allocateDirect(128*128*4).order(ByteOrder.nativeOrder()); bb.position(0); for(int row = 0; row != 128; row++) { for(int i = 0 ; i != 128 ; i++) { bb.put((byte)0x80); bb.put((byte)0xFF); bb.put((byte)0xFF); bb.put((byte)i); } } int[] handle = new int[1]; GLES20.glEnable(GLES20.GL_TEXTURE_2D); GLES20.glGenTextures(1, handle, 0); DrawAdapter.checkGlError("Gen textures"); GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, handle[0]); DrawAdapter.checkGlError("Bind textures"); bb.position(0); GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_RGBA, 128, 128, 0, GLES20.GL_RGBA, GLES20.GL_UNSIGNED_BYTE, bb); DrawAdapter.checkGlError("glTexImage2D"); return handle[0];

    Read the article

  • rotate opengl mesh relative to camera

    - by shuall
    I have a cube in opengl. It's position is determined by multiplying it's specific model matrix, the view matrix, and the projection matrix and then passing that to the shader as per this tutorial (http://www.opengl-tutorial.org/beginners-tutorials/tutorial-3-matrices/). I want to rotate it relative to the camera. The only way I can think of getting the correct axis is by multiplying the inverse of the model matrix (because that's where all the previous rotations and tranforms are stored) times the view matrix times the axis of rotation (x or y). I feel like there's got to be a better way to do this like use something other than model, view and projection matrices, or maybe I'm doing something wrong. That's what all the tutorials I've seen use. PS I'm also trying to keep with opengl 4 core stuff. edit: If quaternions would fix my problems, could someone point me to a good tutorial/example for switching from 4x4 matrices to quaternions. I'm a little daunted by the task.

    Read the article

  • How to attach an object to a rotating circle in box2d cocos2d?

    - by armands
    I am trying to make an object get attached on a collision point to a circle that is rotating, but the player needs to get attached with a constant point on the player. For example the player is moving back and forth and when the user touches the screen and the player jumps up but what I need is that when the player collides with the circle it attaches it's legs to it and continues rotating with the circle. So I wanted to know how to make this kind of collision joint in cocos2d box2d?

    Read the article

  • What's wrong with this OpenGL model picking code?

    - by openglNewbie
    I am making simple model viewer using OpenGL. When I want to pick an object OpenGL returns nothing or an object that is in another place. This is my code: GLuint buff[1024] = {0}; GLint hits,view[4]; glSelectBuffer(1024,buff); glGetIntegerv(GL_VIEWPORT, view); glMatrixMode(GL_PROJECTION); glPushMatrix(); glLoadIdentity(); gluPickMatrix(x,y,1.0,1.0,view); gluPerspective(45,(float)view[2]/(float)view[4],1.0,1500.0); glMatrixMode(GL_MODELVIEW); glRenderMode(GL_SELECT); glLoadIdentity(); //I make the same transformations for normal render glTranslatef(0, 0, -zoom); glMultMatrixf(transform.M); glInitNames(); glPushName(-1); for(int j=0;j<allNodes.size();j++) { glLoadName(allNodes.at(j)->id); allNodes.at(j)->Draw(textures); } glPopName(); glMatrixMode(GL_PROJECTION); glPopMatrix(); hits = glRenderMode(GL_RENDER);

    Read the article

< Previous Page | 323 324 325 326 327 328 329 330 331 332 333 334  | Next Page >