Subset of the OpenGL 3D graphics API designed for embedded devices such as mobile phones.

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0
votes
2answers
239 views

Texture size and scaling, 2D, for OpenGl ES 1.0/1.1

I read everywhere that you have to use a power of two size for your texture width and height, like 16, 32 or 64, but right now my sprite drawing is based on Grid.java from SpriteMethodTest, and I set ...
0
votes
1answer
395 views

“Quad” background showing on OpenGl ES 1.0/1.1 Sprites

I modeled my sprite drawing on Grid.java and GLSprite.java from SpriteMethodTest, using 2D OpenGl ES 1.0/1.1 on Android, but the "quad" sprite background shows when two sprites overlap each other. ...
3
votes
1answer
253 views

Texture mapping a complex object on openGL ES

I dont have much experience with openGL ES (or openGL), but i do get the general idea of texture mapping, which is each vertex should be mapped for the relevant UV coordinates of the texture we choose ...
0
votes
3answers
526 views

How do I “reset” the color in OpenGl ES 1.0/1.1?

In my 2D game I use glColor4f() to set the color and draw my screen border rectangles but when I try to start drawing my game objects, made up of a texture on a rectangular "quad", using ...
2
votes
1answer
361 views

How do I draw an animated object in OpenGL ES?

I have a VBO, which I initialise like this (just an example): - (void)setupVBOs { GLuint vertexBuffer; glGenBuffers(1, &vertexBuffer); glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer); ...
5
votes
3answers
1k views

How long does it take for OpenGL to actually update the screen?

I have a simple OpenGL test app in C which draws different things in response to key input. (Mesa 8.0.4, tried with Mesa-EGL and with GLFW, Ubuntu 12.04LTS on a PC with NVIDIA GTX650). The draws are ...
0
votes
1answer
497 views

libgdx game process dies on loading texture atlases

I try to load a lot of texture atlases (10) with approximately 5 (~2048x~2048)(not using PoT) .pngs each. I'm using AssetManager and there is no trouble with it on my pc but when I try it on my tablet ...
2
votes
1answer
270 views

Color bleed on voxel edges when using anti-aliasing

My Minecraft-like game uses a texture containing four block IDs in each pixel (RGBA). These IDs are used in the shader to determine what color each whole block should be. I'm having an issue with ...
1
vote
0answers
85 views

iPhone 5S - GLSL problem [closed]

I have this shader precision highp float; precision highp int; attribute vec4 POSITION; attribute vec2 TEXCOORD0; attribute vec2 TEXCOORD1; attribute vec2 TEXCOORD2; attribute vec2 TEXCOORD3; ...
1
vote
1answer
492 views

How can I handle errors when there is no valid OpenGL context?

I'm writing cross-platform (iOS, Android, OSX, Windows) library code that draws its output using OpenGL. I expect my users will often try to call my library's rendering functions without a valid ...
3
votes
2answers
1k views

Identity matrix. Confusion. What does it really do

I understand identity matrix is like multiplying to 1. But i can't really understand why would you multiply an a matrix that will only result to the same. Also im messing up with an OpenGL code and ...
0
votes
1answer
591 views

What is Opengl ES ? What is gl and GLES20 mean?

I am new in opengl. I saw tutorial some have gl at the beginning and some have GLES20 at the beginner and some has GL10. What are the differences? Is GLES20 mean opengl es2 whereas GL10 mean version ...
8
votes
1answer
1k views

what is world space and eye space in game development?

I'm reading a book about 3D stuff and OpenGL. The book often talks about world space and eye space. What exactly is the "world space?" Does the "eye space" mean the projection?
0
votes
3answers
1k views

OpenGL ES - read content of VBO

Is it possible to read back content of VBO in OpenGL ES 2.0 ? I have tried glMapBufferOES, but there is no READ flag. I dont want any answers, like "you shouldnt do it" or "keep copy of geometry in ...
1
vote
1answer
213 views

Pixmaps, ByteBuffers, and Textures…Oh my

My ultimate goal is to take a specific region of the screen, and redraw it somewhere else. For example, take a square from the upper left hand corner of the screen and redraw it on the lower right ...
1
vote
1answer
2k views

How to use mipmap in OpenGL-ES

I have recently entered in the OpenGL world. I am very pleased with the performance that I got with opengl compared to those obtained with a SurfaceView and its canvas. At the same time because of the ...
2
votes
1answer
1k views

OpenGL slower than Canvas

Up to 3 days ago I used a Canvas in a SurfaceView to do all the graphics operations but now I switched to OpenGL because my game went from 60FPS to 30/45 with the increase of the sprites in some ...
0
votes
1answer
125 views

How do I load BSP files in Android?

I understand that Opengl directly cannot load BSP files. How would I go about loading them into my Android game?
2
votes
2answers
1k views

OpenGL texture on sphere

I want to create a rolling, textured ball in OpenGL ES 1.0 for Android. With this function I can create a sphere: public Ball(GL10 gl, float radius) { ByteBuffer bb = ...
1
vote
1answer
3k views

How to do frame by frame animation in android using open gl es

I have application in some part i am using AndroidDrawable for animation but it giving jerking effect that why i planed to change the code to Open Gl ES for better performance .so far i have googled ...
4
votes
1answer
199 views

GetData() error creating framebuffer [closed]

I'm currently porting a game written in C# with XNA library to Android with Monogame. I have a Texture2D and i'm trying to get an array of uint in this way: Texture2d textureDeform = ...
1
vote
1answer
827 views

rendering transparent meshes in LibGDX

Building open this tutorial - https://code.google.com/p/libgdx/wiki/ProjectionViewportCamera I have constructed a class for generating polygon meshes. But i cannot figure out how to render semi ...
1
vote
1answer
1k views

how to make cross platform 3d games using modern opengl? [closed]

How to create games that run on windows, Linux, mac os x, android, ios, wp8 etc.... using c/c++, opengl 3 or 4 and opengl es 2.0. any tutorials or videos on how to create cross-platform 3d games.
6
votes
1answer
1k views

Sprite sheet textures picking up edges of adjacent texture

I have a custom sprite routine (openGL 2.0) which uses a simple sprite sheet (my textures are arranged horizontally next to each other). So, for example, here is a test sprite sheet with 2 simple ...
-2
votes
2answers
131 views

In OpenGL, how to confirm a primitive is rendered properly

I have to confirm that a primitive (say triangle) is rendered properly in opengl. I can use the glGetError() after a opengl draw calls(glDrawElement/glDrawArrays) Is it enough to confirm ? Is there ...
1
vote
0answers
60 views

OpenGL ES - jagged edge [duplicate]

I need to render roads and some direction marks on top of them. I render roads as triangled geometry, same goes for marks (see picture - road is purple, mark is red, ignore z-fighting). Problem goes ...
1
vote
1answer
203 views

Android Object get Jagged at the border

I am new to OpenGL ES 1 in android. My 3D Model border getting Jagged. Please help me to look like a smooth border instead of jagged. Screenshot : http://i.stack.imgur.com/1Gq83.png private class ...
0
votes
1answer
223 views

How to set tranparency for one image only in openGL ES in Android?

I code game on Android where I have several sprites. My goal is to set gl.glColor4f(1f, 1f, 1f, 0.2f) a.e. transparency only for specific image. (I don't like Photoshop). In my case its image that ...
1
vote
0answers
268 views

OpenGL ES for Samsung 4 - no textures only white rectangles [closed]

I have Nexsus 4,Samsung 3 and several HTCs and my game works fine. When I launch on Samsung 4 I see white rectangles (empty textures), no errors, Further, my game uses sensors but I see on ...
2
votes
1answer
1k views

How to scale openGL textures by a ratio based on height/width (or alternative)

I have been able to successfully allow my UI to extend over edges of my game on higher resolutions by using the Android Guide and by implementing this code on the GL10 object: ...
2
votes
1answer
434 views

How to know in OPenGL ES android that one object crosses another?

I have 2 objects on the screen: static: non-static: non-static object moves randomly over the screen. How do I know that non-static Object cross the "+" (static). Both objects I draw by using ...
2
votes
1answer
498 views

What is the correct and most efficient approach of streaming vertex data?

Usually, I do this in my current OpenGL ES project (for iOS): Initialization: Create two VBO's and one IndexBuffer (since I will use the same indices), same size. Create two VAO's and configure ...
0
votes
1answer
2k views

How to get drawn Image width/height on the screen with openGL ES on Android?

I need to know how to get drawn image length and width. I have this code so far where I draw Radar in left top corner with hard-coded coordinates: int _SRC = R.drawable._item; ... float ...
3
votes
2answers
1k views

How do I clip an image in OpenGL ES on Android?

My game involves "wiping off" an image by touch: After moving a finger over it, it looks like this: At the moment, I'm implementing it with Canvas, like this: 9Paint pTouch; 9int X = ...
2
votes
0answers
452 views

multi-threading for openGL in Android? [closed]

In my old game based on canvas and bitmaps I used surfaceHolder and Thread to call onDraw: public class GameThread extends Thread { private SurfaceHolder _surfaceHolder; private ScreenObjectsView ...
5
votes
2answers
2k views

Using two shaders instead of one with IF statements

I've been working on porting a relatively large opengl ES 1.1 source to ES 2.0. In OpenGL ES 2.0 (which means, everything uses shaders), I want to draw a teapot three times. The first one, with a ...
3
votes
2answers
161 views

How to change dynamically vertices during call “draw” method?

I'm new in openGL world and I try to figure out followed problem: How can I change size/zoom dynamically for my spritesheet. This class represents some creature fetched from spritesheet and animate ...
4
votes
1answer
214 views

Is it possible to apply a texture inside a GL_LINE_LOOP?

I am creating a game using Box2D and OpenGL ES 1.1. I am taking the b2PolygonShape vertices and converting them into an OpenGL ES 1.1 GL_LINE_LOOP. The debugging view looks great, but now I want to ...
0
votes
2answers
5k views

How to create a projection matrix in OpenGL ES 2.0 [closed]

So I have the following... float s = 0.5f; void renderFrameLine() { glClearColor(0.0f, 0.0f, 0.0f, 1.0f); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); GLfloat vVertices[] = { s, s, ...
0
votes
1answer
2k views

Rendering Texture Quad to Screen or FBO (OpenGL ES)

I need to render the texture on the iOS device's screen or a render-to-texture frame buffer object. But it does not show any texture. It's all black. (I am loading texture with image myself for ...
0
votes
1answer
1k views

Android/OpenGL ES2: How do I set fragment shader value using C;

This should be easy So I am using the following to create a fragment shader. GLbyte fShaderStr[] = "precision mediump float;" "void main() \n" "{ ...
3
votes
2answers
1k views

OpenGL ES 2.0: 2D game rendering, no performance gain with glDraw call batching

I just did a small benchmark. To my surprise batching sprites into a single draw call doesn't give any significant performance boost. Following are my results: Hardware: iPod touch 4 Extra info: ...
7
votes
1answer
2k views

Optimizing performance of a heavy fragment shader

I need help optimizing the following set of shaders: Vertex: precision mediump float; uniform vec2 rubyTextureSize; attribute vec4 vPosition; attribute vec2 a_TexCoordinate; varying vec2 tc; ...
3
votes
2answers
875 views

OpenGL ES 2.0: Enabling hi-res on iOS

I created an empty iOS project and then added a custom GLView class which is then added to AppDelegate. I have following questions: 1) How do I enable hi-res retina mode on iPhone 4? Currently I am ...
1
vote
2answers
726 views

Calling glGetError() in release builds?

Currently, I'm calling glGetError() after each OpenGL function call in order to be able to detect and report bugs. I've been reading that glGetError() calls should be reduced to once per frame in ...
0
votes
1answer
702 views

iOS OpenGL ES 2.0 How to Billboard on Sphere and Rotate with Sphere

I have a sphere (earth) in OpenGL ES 2.0 for iOS. I also have markers that I want to place at lat/lons on the earth - but I want the markers to always face the user ( billboards ) but also move with ...
0
votes
1answer
241 views

bump mapping with 2 normal maps

I was wondering if its actually possible to do bump mapping with 2 normal maps... I have tried doing it this way however I get a function overload on max and dot. uniform sampler2D n_mapTex; uniform ...
0
votes
1answer
187 views

texture movement stutters

Hey I at the moment I have got my texture to move however it stutters as I increment by 0.001 every second. My animation is done via FPS if that make sense and here is some code FrameCount++; ...
0
votes
1answer
396 views

texture won't move OpenGL ES 2.0

I want be able to move my texture in GLSL I have set my texture to wrap S and wrap T but not sure why it wont move my fragment shader looks like this at the moment uniform sampler2D n_mapTex; ...
2
votes
1answer
117 views

OpenGL ES Single Bitplane Texture (or something close)

I'm looking to use a texture to store single bits (or a low number of bits, two or three). This in of itself isn't hard if you're using nearest neighbor sampling with some bit plane unpacking. The ...