opengl-es

Roadmap to Android development

Hello, I've done a little research, and am interested in developing for Android. I've never programmed before, and have no idea how to go from zero experience to developing for a mobile device. My interest is in eventually making some sort of 2d game. Is there a lesson plan for starting from the ground up? I would think one would ...

converting 2D mouse coordinates to 3D space in OpenGL ES

I want to convert mouse's current X and Y coordinates into the 3D space I have drawn in the viewport. I need to do this on the OpenGL ES platform. I found following possible solutions implemented in OpenGL, but none fits what I am looking for. I found NeHe's tutorial on doing exactly this, but in traditional OpenGL way. It uses gluUnPr...

Corrupted image if variable is not static

I'm doing the following: static GLfloat vertices[3][3] = { {0.0, 1.0, 0.0}, {1.0, 0.0, 0.0}, {-1.0, 0.0, 0.0} }; glColor4ub(255, 0, 0, 255); glEnableClientState(GL_VERTEX_ARRAY); glVertexPointer(3, GL_FLOAT, 0, vertices); glDrawArrays(GL_TRIANGLES, 0, 9); glDisableClientState(GL_VERTEX_ARRAY); This works ok: Howev...

Trouble with onscreen keyboard orientation in iPhone OpenGL ES application.

I need to take keyboard input in my OpenGL ES application, so I just created a hidden UITextField and added it as a subview to the main window along with the view that presents my content. I use the UITextField to control the keyboard and it works fine in a single orientation. I then changed my code to support all orientations by rotati...

iPhone. Particle system performance

I try to draw rain and snow as particle system using Core Graphics. In simulator rendering proceeded fine but when I run my app on real device rendering is slow down. So, advise me please approaches to increase particle system drawing performance on iPhone. May be I should use OpenGL for this or CoreAnimation? ...

How does glClear() improve performance?

Apple's Technical Q&A on addressing flickering (QA1650) includes the following paragraph. (Emphasis mine.) You must provide a color to every pixel on the screen. At the beginning of your drawing code, it is a good idea to use glClear() to initialize the color buffer. A full-screen clear of each of your color, depth, and stencil buffers ...

iPhone OpenGL ES - How to Pick

I'm working on an OpenGL ES1 app which displays a 2D grid and allows user to navigate and scale/rotate it. I need to know the exact translation of View Touch coordinates into my opengl world and grid cell. Are there any helpers to do the reverse of last few transforms which I do for navigation ? or I should calculate and do the matrix st...

How do I use the gravity vector to correctly transform scene for augmented reality?

I'm trying figure out how to get an OpenGL specified object to be displayed correctly according to the device orientation (ie. according to the gravity vector from the accelerometer, and heading from compass). The GLGravity sample project has an example which is almost like this (despite ignoring heading), but it has some glitches. For ...

What can we use instead of blending in OpenGL ES?

I am doing my iphone graphics using Opengl. In one of my projects i need to use an image, which i need to be used as a texture in opengl. The png image is 512 * 512 in size, its background is transparent and the image has a thick blue line in its center. When i apply my image to a polygon in opengl, the texture appears as if, the trans...

Loading .png image from array of uint8_t into OpenGL ES texture

Normally, when we want to load a texture for OpenGL ES with .png, we simply add the .png images into XCode. The .png files will be altered for optimization by XCode and these altered png files can loaded into OpenGL ES texture during the runtime. However, what I am trying to do is quite different. I am trying to load a .png file that i...

File Translator to Export Animated 3D Character from Autodesk Maya as Quake MD2

I'm wondering if anyone knows of a way to export geometry/textures for a rigged, animated character as Quake MD2? I’m developing an app for mobile devices, and I’ve found that MD2 works great for lightweight OpenGL rendering. I have several animated characters, and I’d like to export them as MD2 from Maya. Here are some of the things I h...

Accuracy of OpenGL ES Instrument

I'm developing a game for the iPhone. I've decided that 30FPS is plenty so I've written some code that only allows the App to present the render buffer every 1/30 of a second. When I tried to verify this with Instruments I got varying information. On an iPod Touch (2009 edition, 32G) it reports 30 FPS for Core Animation Frames Per Sec...

Is there any way to add alpha to individual vertices in OpenGL Vertex Buffers?

Hello, I'm trying to learn how to use vertex buffers by making a sprite engine. I create a new buffer for each texture page I have, and can add instances of textured quads to the buffers, interleave their vertex and uv information and render them out fine using DrawElements. However, I can't find any way of setting the alpha on individ...

Android Live Wallpaper: waitForCondition(ReallocateCondition)

I've been developing a live wallpaper using GLWallpaperService, and have gotten good results overall. It runs rock-solid in the emulator and looks good. I've dealt with OpenGL many times before so have a solid command of how to do things... unfortunately I'm having a hell of a time getting this to actually be stable on the actual hardw...

What is the best software for creating OpenGL ES models and textures?

Hi everybody What is best software for creating models , textures etc... for iphone development. From simplest to more complex programs. First thing that comes to my mind is blender , but I'm curious what everybody else is using and their opinions. ...

OpenGL ES 2.0 FBO creation goes wrong with unknown error

I've been struggling with this for a while now, and this code crashes with, to me, unknown reasons. I'm creating an FBO, binding a texture, and then the very first glDrawArrays() crashes with a "EXC_BAD_ACCESS" on my iPhone Simulator. Here's the code I use to create the FBO (and bind texture and...) glGenFramebuffers(1, &lastFrameBuffe...

Fast way to perform addition of 2 LARGE float arrays in Android. Optional JNI or Opengl ES

I simply need to add floatArray1 to floatArray2 storing the result in floatArray2.. no third array.. all arrays are one dimensional but are very large... probibly as large as the os will let me get away with. Max i would need is two float arrays with 40,000 floats each... but i could get away with 1/10th that i suppose minimum. Would lo...

Adding procedural C openGL functions to an iPhone project

I want to add a few drawing functions to an iPhone project for drawing things. Something like drawTile(x,y,len,wid); which would call openGL to draw a box somewhere. I should just be able to write a procedural C file to do this but the openGL libraries are objective C and I'm getting weird errors. Do I have to make a class for all of my ...

openGL ES gpu thread on android devices

does anyone know what part of the opengl es thread on an android device runs on the gpu (if it has one). just the method calls you make with the GL10 adapter class? or the complete onDraw method in your custom Renderer class? ...

iPad OpenGL ES FPS too slow!

I'm currently working on an OpenGL ES 1.1 app for the iPad its running at full 768x1024 iPad resolution, with textures, polygons, and the works but only at about 30 fps! (not fast enough for my purposes) im pretty sure its not my code, because when i lowered the resolution, the FPS increased, eventually the normal 60 at iPod touch res...