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

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if a desktop machine supports OpenGL 3.0+ I can assume that it supports OpenGL ES 2.0 too?

This isn't clear for me, if i use the drivers from the GPU manufacturer and they support OpenGL 3.0 and/or above, i can always make an OpenGL ES 2.0 application work?
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1answer
1k views

Reducing Memory Use on OpenGL ES

I'm using an opengl es based framework to create my game.I have an out of memory problem on some devices.I have 15 textures with a size 1024x1024(totally 10 mb).On memory they covers a lot of ...
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3answers
1k views

glGetFloatv – should it be avoided? Can it be replaced?

Platform is OpenGL ES 1.x. I am using glGetFloatv() to get MODELVIEW matrix. This allows me to compute points, where I need to draw a shadow effect. This is very handy, as I can forget about ...
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1answer
130 views

android opengl-es spritesheet display number

Whats the best way to display numbers on android with opengl using a spritesheet? I like to display the number "294" using the spritesheet: http://i.stack.imgur.com/wv5Zh.png
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2answers
804 views

Android OpenGL textures sometimes corrupted

Just trying to get some sprites (textured squares) to draw from a texture atlas and 50% of the time after the application is first launched/ reorientated/ brought from sleep these various graphical ...
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2answers
441 views

Can I dynamicaly modify 3D objects?

I am new to OpenGL, I am able to render a model object (a human model) that is using .obj and .mtl file in iOS. Now I want to make a modification to the loaded model. For example, I want to change ...
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1answer
3k views

Sea water shader using only fragment processor

I have a game that runs on mobile devices (OpenGL ES 2.0) and for which I would like to create some sea water using the shaders. Now, the plane on which the sea water texture will be has only 4 ...
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2answers
397 views

Lights system with shaders in OpenGL?

In more than just 1 occasion, i read about 2 ways of doing a light's system in OpenGL: normal way? i don't know how to call this one with the shaders ( GLSL ) The problem is i don't get the ...
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1answer
111 views

Touch point on the near plane

I have a matrix created with either orthoM or frustumM GL function, where the near plane is logically the surface of the tablet. I would like to translate touch locations to their location on the near ...
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1answer
2k views

OpenGL ES 2.0 Best Practices / Architecture Guide

I've recently started working with OpenGL (ES 2.0) on the Android. While there is lots of documentation about the basics, I can't seem to find much about the overall architecture of OpenGL. In ...
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1answer
1k views

Shader authoring/editing tools for GLSL ES

Since Render Monkey has been discontinued (perhaps due to the complexity of today's shading languages), there are few successors that can match its functionality. Is there any useful tool for material ...
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3answers
4k views

OpenGL ES and Screen Coordinates

Is there anyway I can make OpenGL ES 2.0 to accept coordinates (for Vextex for example) in int meaning the pixels instead of the default float system? Also how can I set the point (0,0) to be at the ...
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1answer
615 views

How to obtain contrail visual effect?

I have objects moving in OpenGL ES1 application. I want some of them to leave behind contrail – like if they would emit some radiation or something. EDIT: the kind of contrail is: light contrail – ...
4
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1answer
715 views

Creating a highlight halo around a selected object

I'm looking to create a halo highlight around the selected objects in my game screen. The main platform is android, but I am writing an iOS version as well, updating it whenever I successfully add the ...
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1answer
495 views

Why is my mesh generation algorithm not working properly?

I am trying to generate a grid in OpenGL ES, using known methods for triangle strips and stitching as shown in: this post and this post The code below, generates the vertices for a 4x4 grid with a ...
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1answer
2k views

2D Quads : Translation with OpenGL ES 2.0 on Android [closed]

I have a simple 2D engine that renders 2D textured quads, and right now I can scale the quad or rotate it, but when I try to translate it I have a strange distortion (the quad is squashed in the half ...
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1answer
3k views

How to display bitmap using Texture api in android opengl

I want to display a bitmap image at screen using texture api in android opengl. Some code which I have used in our code as below. public void onSurfaceChanged(GL10 gl, int width, int height) { ...
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0answers
248 views

Getting contour without the background [closed]

I have a texture and vertex which are needed to create a set of closed polygons. For this purpose I use these functions: Code for create texture: CCSprite* spr = ...
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0answers
201 views

Remove “dots” noise (like from dot-matrix printer)

I have 2D array of floats. Using the floats, I generate image by doing proportional selection of color from between COLOR_MIN, COLOR_MAX – for maximal float value at given (x,y), I choose COLOR_MAX ...
4
votes
2answers
435 views

Geometry vs sprites

I'm developing an android game, where the enemies are geometrical shapes. Performance is a main goal for me so I was wondering if defining shapes directly in OpenGL would be more efficient than using ...
2
votes
3answers
3k views

How do I render .dae models?

I'm building a game for iOS. I'm quite new to OpenGL but what I want is to take a 3D model I have made in Google SketchUp and use it in my 3d game. The problem is I don't know how to proceed. I have ...
3
votes
2answers
5k views

Creating an OpenGL FPS camera: I have the position and orientation vectors, now what?

I have been struggling to create a first person camera in OpenGL ES 2.0 without using gluLookAt(). I grab the camera's orientation vectors (the way it's looking) from the current modelview matrix, and ...
7
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2answers
3k views

OpenGL ES 2.0: Mixing 2D with 3D

Is it possible to mix 2D and 3D graphics in a single OpenGL ES 2.0 game, please? I have plenty of 2D graphics in my game. The 2D graphics is represented by two triangular polygons (making up a ...
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2answers
3k views

How to use OpenGL's glUseProgram?

While in the rendering loop, is it OK to call glUseProgram? Does it have a big overhead? I'm planing to use a program for each different material in the scene. I'm a real beginner with OpenGL and I'm ...
5
votes
4answers
4k views

Geometry instancing in OpenGL ES 2.0

I am planning to do geometry instancing in OpenGL ES 2.0 Basically I plan to render the same geometry(a chair) maybe 1000 times in my scene. What is the best way to do this in OpenGL ES 2.0? I am ...
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0answers
346 views

Camera rotation flicker in OpenGL ES 2.0

I implemented an orbit camera in my own OpenGL ES 2.0 application. I was getting extensive amount of flicker while rotating the camera using the mouse. When I added the line eglSwapInterval( ..., ...
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1answer
150 views

Drawing texture does not work anymore with a small amount of triangles

When i draw lines, the vertices are well connected. But when i draw the texture inside the triangles, it only works with i<4 in the for loop, otherwise with i<5 for example, there is a ...
1
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1answer
319 views

Adjust sprite bounds of the visible part of texture

Is there any way to adjust the boundaries of the visible part of the sprite? To make it easier to understand: I have a texture, such as shown at figure 1. Then I break it into pieces and fill the ...
10
votes
3answers
4k views

How can I bend an object in OpenGL?

Is there a way one could bend an object, like a cylinder or a plane using OpenGL? I'm an OpenGL beginner (I'm using OpenGL ES 2.0, if that matters, although I suspect, math matters most in this case, ...
1
vote
1answer
2k views

Texture displays on Android emulator but not on device

I have written a simple UI which takes an image (256x256) and maps it to a rectangle. This works perfectly on the emulator however on the phone the texture does not show, I see only a white ...
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2answers
3k views

How to determine counter-clockwise vertex winding

I've been causing myself some confusion lately with regards to vertex winding in a mesh class that i'm writing. Currently, the mesh contains the appropriate structures for: vertices (vector3) ...
1
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1answer
705 views

OpenGL ES 2 - glSwapBuffers?

this is what i do to blit FBO onto screen in ViewController: [m_Context presentRenderbuffer:GL_RENDERBUFFER]; but i need something like glSwapBuffers, so that i can call it somewhere from the ...
0
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1answer
375 views

Straightforward guidelines for converting OpenGL to OpenGL ES?

Is there a straightforward list of finite steps that I need to follow to convert an OpenGL program into an OpenGL ES that's used on the iPhone and iPad? I'd be using GLKit. I've seen some similar API ...
5
votes
3answers
14k views

glTranslate, how exactly does it work?

I have some trouble understanding how does glTranslate work. At first I thought it would just simply add values to axis to do the transformation. However then I have created two objects that would ...
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1answer
872 views

Where to start creating a 2d rain simulation with OpenGL ES 1.1?

I'm using opengl 1.1 and i'm creating a 2d side scrolling game.How can i render a 2d rain simulation?What is logic for that?
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2answers
1k views

Problem with drawing textures in OpenGL ES

I'm developing a 2D game for Android and i'm using the framework which has been told in the book which named Beginning Android Games by Mario Zechner.So my framework is well designed and using OpenGL ...
0
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1answer
377 views

Triangles in a C++ STL Vector as an Objective-C member sometimes draws incorrectly in OpenGL ES

The polygons draw correctly 80% of the time. When it fails, a vertex is dislocated. The polygon is consistently drawn with the wrong vertex. I checked that the vector is correct during initialization, ...
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1answer
363 views

From simple physics with a ball, to a more complicated shape

Hello fellow game devs and stack overflowers... I recently made a transition from OpenGL ES 1.1 to 2.0 (on Android via NDK) and things are going well so far. I'm working on doing a dice rolling ...
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1answer
1k views

Handling different screen densities in Android Devices?

Well, i know there are plenty of different-sized screens in devices that run Android. The SDK I code with deploys to all major desktop platforms and android. I am aware i must have special cares to ...
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3answers
5k views

Open GL ES 2.0 with Android

I was wondering if someone could recommended a book that covers both android game developement and OpenGL ES 2.0. I have found some books with OpenGL 1.0, but I have heard that the syntax for OpenGL ...
0
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1answer
917 views

Determining and culling non-visible vertices

Ahoy! After posting my previous question on tile maps, i've been tinkering with an implementation i'm rather pleased with so far but would like to gather some more information about submitting ...
3
votes
1answer
600 views

Can glTexImage2D() use an already existing memory block?

Can I use glTexImage2D() and / or glTexSubImage2D() (or maybe there's some other method I don't know about) with an already existing block of memory, instead of always uploading the changed pixels? I ...
0
votes
4answers
1k views

Should I use a VBO if the vertex data changes from time to time?

If I have a very large number of vertices, but they're static for about 70% - 80% of their life time, should I use a VBO for them? If so, what usage should I specify? This doesn't sound like a case ...
8
votes
2answers
4k views

Tile map/terrain implementation with differing heights of neighbouring tiles

Ahoy! I'm looking for some information about tile maps, or rather, what a specific type of tile map is called. I'm interested in the kind of implementation used in rollercoaster tycoon, or the ...
1
vote
1answer
911 views

How can I add a parallax effect into my side-scrolling game? [duplicate]

How can I add a parallax effect into my side-scrolling game? I read a lot about parallax scrolling so I know what the logic is and what parallax is but I can't create a dynamic parallax effect. I ...
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1answer
725 views

Scrolling and Parallax scrolling in 2D game

I'm developing a 2D side-scrolling game.I have a scrollable bitmap for background with size 2400x480.How can i scroll this bitmap?I have searched for algorithms but i can't find any solution. I know ...
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1answer
781 views

Keeping track of onscreen objects in opengl es on Android

In a small game Im working on I was able to implement ray picking with an opensource 3d engine called min3d but I cant figure how to keep track of what object is onscreen. I will some times have ...
3
votes
1answer
1k views

Android how to get opengl 3D coordinates in ontouch event

I created a cube in opengl and it rotates in ontouch event. To to this I created a CustomSurfaceView as follows public class CustomSurfaceView extends GLSurfaceView { @Override public boolean ...
2
votes
1answer
2k views

Open GL Android frame-by-frame animation tutorial/example code

My first question was asked wrong, so I need to ask again :) I found out, that I will have to do an OpenGL animation for my Android game. The closest (known) example is Talking Tom (but I don't know ...
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3answers
933 views

does opengl automatically handle offscreen rendering?

I'm wondering if opengl can automatically manage offscreen rendering. I mean if it can detect and ignore sprites and textures if they are rendered out of screen. if it makes any difference i'm ...