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

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3
votes
3answers
156 views

How to hide a post-processed mesh outline when/where the mesh is hidden

I'm working on setting up an active outline in my 3d engine, a highlight effect for selected 3d characters or scenery in the screen. After working with the stencil buffer and getting some ...
2
votes
1answer
194 views

How to clip or mask entity in adnroid/andengine?

I want to implement masking with sprite in Andengine. I want same functionality as in ios class called SKCropNode which works like an masking node! Is there any workaround like this in ...
1
vote
1answer
28 views

How to map control key to a specific angle or orientation?

At the moment, I basically have built out a large hash table of various angles and what direction they map to, if the user would press right, up, down, left. This is needed, in my case, as I have a ...
1
vote
1answer
58 views

cannot implement GLSurfaceView.RENDERMODE_WHEN_DIRTY

I'm trying simply to display an openGL surface when I click the screen using GLSurfaceView.RENDERMODE_WHEN_DIRTY mode but the surface does not display when I click it , why ? my Activity : public ...
1
vote
1answer
151 views

OpenGL: How to map point inside frustrum to normal device coordinates (NDC)?

I read this article http://www.songho.ca/opengl/gl_projectionmatrix.html. It's explain how calculate projection matrix coefficients. But I completely can't understand how author perform mapping from ...
1
vote
1answer
469 views

Transparency in GLSurfaceView

I'm new in game development. I have a view using GLSurfaceview and call in MainActivity. i want to make transparent that view. i have tried setZOrderOnTop() method in MainActivity and glClearColor() ...
-1
votes
1answer
688 views

2d triangle with OpenGL-Es on Android

hey I am trying to draw a triangle on opengl es . I just followed a tutorial to do it. eventhough everything seems to be fine it does not work. everytime I run my code it sends me back to main menu. ...
5
votes
0answers
90 views

OpenGL: Frame partially jumps back and forth

I'm working on a project with SDL and OpenGL. The game works great on Windows, Linux, OS X and iOS. However, the Android version is showing a problem on my phone in particular. I have tested another ...
2
votes
0answers
108 views

Texture coordinates for custom geometry in SceneKit ios9

I am trying to texture the a custom plane shape I created in scenekit on iOS9. I need the texture to spread out and stretch over the entire surface. I have a vertex and fragment shader on an ...
2
votes
0answers
78 views

Using depth values for fake ambient occlusion

I'm using the normalized distance to the camera to get depth information in the fragment shader. When using this value as fragment color, it looks at lot like ambient occlusion (of course only in the ...
2
votes
0answers
806 views

Weird y offset when using custom frag shader (Cocos2d-x)

I'm trying to mask a sprite so I wrote a simple fragment shader that renders only the pixels that are not hidden under another texture (the mask). The problem is that it seems my texture has its y-...
2
votes
0answers
342 views

iPhone GLSL shader dynamic branching issue

I am trying to pass an array of vec3 as uniform and then iterate through them on each pixel. The size of array varies on situations so I can't make the loop with constant number of iterations. ...
2
votes
0answers
1k views

Depth sorting 2D textures in a batch with OpenGL ES 2.0

I have a combo of texture atlases and sprite batches in an OpenGLES 2.0 2D game I'm developing which is working well, but I have a problem with depth sorting. I'm using atlases to reduce the number ...
2
votes
0answers
149 views

Is there a way to export 3D objects with animation from Blender or any other app into OpenGL ES 1.1 code?

The problem is that all the examples I've found are obsolete or iOS/Android specific and not "pure" OpenGL ES 1.1. If anyone can provide me with a good example/tutorial/book it would be very much ...
1
vote
0answers
7 views

Making use of the Android GPU debugging tools

I tried following the manual to install the Android GPU debugging tools for android Studio 2.0. Unfortunately it has not been very successful. I have been following the instructions of the official ...
1
vote
0answers
17 views

OpenGL ES 2.0 not drawing images with shadows

I'm using OpenGL ES 2 to program a simple game 2D for Android mobile phones. I'm coding the rendering portion of the software, using the GLES20 default library. All my sprites are rendered from a ...
1
vote
0answers
91 views

How to draw 2D pixel data with OpenGL

I am fairly new to OpenGL. I have a 2D game in SDL2 that uses currently works by creating a SDL_Surface from the pixel data, copying it into a SDL_Texture, and rendering it to the screen with ...
1
vote
0answers
31 views

Logical operations per component in GLSL

According to the OpenGL spec in GLSL, the logical operators: &&, || etc work between booleans, not vectors of booleans. So, what is the best way to perform the logical and/or per component in ...
1
vote
0answers
46 views

Stencil buffer confuse

I was trying to make two object outline. One would color the object with orange and other with green. I just wanna know if is it possible to have two object outline at the same time because every time ...
1
vote
0answers
31 views

How to use quaternion on another referential

I'm new on Three.js and despite a mechanical background, I can't find how quaternion works: it's like it always refers on local part referential and not the global one. I've illustrated it here : ...
1
vote
0answers
130 views

How do I draw multiple irregular polygons with OpenGL ES?

In this post I was asking how to program a map of a Risk-like game. Now that the map is pretty coded, both client and server-side, I'd like to finally draw the map. I'll try to keep least broad as ...
1
vote
0answers
718 views

Libgdx implement 2d drop shadow for transparent sprites

I am a libgdx learner. For an learning application that I am developing using libgdx on android, I need to show drop shadow or glow effect when a sprite is touched. The sprites are created from a ...
1
vote
0answers
152 views

How to render multiple objects as a single object for fluid simulation?

I'm trying to do fluid simulation using particles in 2d game. I have larger particles, which interactive each other physically, those particles collide with environment (e.g wall,obstacles) to ...
1
vote
0answers
106 views

Weird blending behavior on PowerVR SGX544MP2

On PowerVR SGX544MP2, sometimes blending behaves in a very strange way for me. Instead of blending with the actual color from the previous draw calls, it tries to blend with black: (sorry about the ...
1
vote
0answers
58 views

Android OpenGLES, getting number of fragments passed depth test/Occlusion Query?

Afeter reading many blogs and searching on Internet, I did not get any sloution for getting number of fragments/pixels which are occludded or not occludded of the object on OpenGL ES3.0 Android ...
1
vote
0answers
123 views

LibGDX: Why look BitmapFont pixelated on a scene2d.ui.Dialog?

When I use BitmapFonts directly on the stage table, the fonts looks normal (not pixelated). But when I use the same BitmapFont with the same size on a scene2d.ui.Dialog, the font looks pixelated. ...
1
vote
0answers
497 views

How can I reduce draw calls when using glBufferSubData and DYNAMIC_DRAW?

At first I had the problem where I had about 150 rectangles rendered every tick. I only used STATIC_DRAW and glBufferData. I added support for DYNAMIC_DRAW and glBufferSubData and now I have a very ...
1
vote
0answers
310 views

How can I use a Seekbar as a brightness slider?

I am using the GLSurfaceView Renderer. I want changes to a seek bar's progress to increase the brightness of a GLSurfaceView proportionally. How do I apply a color matrix to a GLSurface view? Is ...
1
vote
0answers
414 views

iOS OpenGLES - Multithread Game loop - Render and Update

I am trying to implementing multi-threaded game loop in iOS. (Actaully, two thread - Render and Update) This is my structure. Update Loop Has logic and at the end of loop, save update state. (...
1
vote
0answers
82 views

Android opengles how to use glunproject

How to use glunproject in my android app? I have the following parts in my engine: A projection matrix A view matrix for the camera A model matrix for each of the objects in my world. This matrix ...
1
vote
0answers
214 views

Android multi screen rendering

Is it possible on Android to render specifically / only, to the connected Monitor/TV on the hdmi port? If so, is it possible to use OpenGL ES to render a different scene on the monitor and on the ...
1
vote
0answers
561 views

To stop Spite animation scrolling along the background in openGL ES

After using the endless road algorithm as described here, I also implemented the scrolling of walls along with it. I have the walk animation of the person which is stationed at the center of the ...
1
vote
0answers
229 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 ...
1
vote
0answers
919 views

OpenGL ES multiple objects not being rendered

I am doing the following to render multiple balls move around the screen but only 1 ball is seen to appear and function. I don't know why the rest (count-1) balls are not being drawn public void ...
1
vote
0answers
864 views

Rotation deforming mesh (Opengl ES 2.0)

I'm trying to render a rotating cube on Opengl ES 2.0, using some math classes I wrote (based on a lot of online and offline info) for quaternions, matrixes and the like. As far as I know all the math ...
0
votes
0answers
50 views

glMapBufferRange performance on devices with shared memory

I have a few questions regards to the glMapBufferRange performance on devices with shared memory between CPU and GPU (OpenGL ES 3 capable Android devices to be specific). 1 - Is the mapped buffer ...
0
votes
0answers
36 views

How to scale the camera

I'm developing a game engine (for the sake of knowledge) using OpenGL ES 1.x (Android). And there is a problem with scaling. To ensure that all textures are displayed correctly on various devices I ...
0
votes
0answers
26 views

OpenGL ES vertex/fragment shaders - Blinn phong

I'm developing a simple educational project to study OpenGL ES. I'm try to render some simple OBJ models using Blinn-Phong. The first version of the of my implementation calculate all the lighting ...
0
votes
0answers
73 views

YUV target on GL_TEXTURE_EXTERNAL_OES

I am using a surface texture bound to GL_TEXTURE_EXTERNAL_OES. I read that the GL_TEXTURE_EXTERNAL_OES texture target is usually in a YUV color space. I want to take "y" value for each pixel in ...
0
votes
0answers
41 views

OpenGL ES 2.0 how to access LUT

I've created a look up table for my fragment shader and I'm passing it in as a uniform float array. uniform float hueLut[360]; My program works fine on most devices but I ran across one device ...
0
votes
0answers
48 views

Capture what is Rendered in OpenGL

Im Making an android Game with OpenGl ES, I Want to capture what is rendered onto screen By FloatBuffer and save it for later use, For Example If this is the OutPut: I want this for Result: How ...
0
votes
0answers
71 views

Camera rotation destroy scene objects orientation

I fight with that for some time and searching internet but I don't have any answer for my problem. In few words i want to have orbiting camera on screen and objects which I want also rotate ...
0
votes
0answers
117 views

Make a layer over an image and adjust its co-ordinates by touch

I need to make a layer over an image and adjust the layer to fit to image and get its co-ordinates of the layer. I need to adjust the layer by touch and pinch. The sample image is as below. I need ...