OpenGL ES 2.0 emphasizes a programmable 3D graphics pipeline (comparing to fixed-function pipeline of OpenGL ES 1.1).

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2
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1answer
453 views

Generate ETC2 compressed texture from Android Bitmap in OpenGL ES 2

My app currently uses a lot of textures most of which probably could be compressed quite a lot by using ETC2 (my app runs on 4.4 so i have a lot of devices supporting GLES30), i cannot use ETC1 since ...
0
votes
1answer
30 views

Opengles 2.0, Replace the black region in the image to make it transparent

I have two textures, Source image A and Overlay B, B is drawed on top of A, I want to replace the black color in B, then make the region of A visible, what should I do? This is my shader language: ...
5
votes
1answer
276 views

What's the best practice for a progress bar in OpenGL ES 2.0 (Android)

As the title says, what is the best practice for a progress bar in OpenGL ES 2.0 on Android ? My attempt: I make a texture (could be a single colour or otherwise), and then stretch that texture from ...
0
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0answers
20 views

Emscripten / webgl lazy rendering?

I compiled existing opengl es 2.0 code to webgl using emscripten. In the desktop version there is lazy rendering mechanism that only renders when required which is basically just saying invalidate ...
2
votes
0answers
105 views

Bilinear filtering by sampling corners of a texel

I'm trying to do bilinear filtering in texels to get the convoluted value of a 3x3 block. Implemented as below: offsetx = 1/width offsety = 1/height Fragment shader: "varying vec2 vTextureCoord;\n"...
2
votes
1answer
243 views

Looking for specific “textured quad” openGL tutorial in c++ [closed]

I'm new to openGL and I've been googling around for the old and simple textured quad tutorial in openGL but I haven't been able to find one that suits my needs. OpenGL3.X compatible OpenGL|ES 2.0 ...
1
vote
1answer
31 views

How to know when Android OpenGL Context has been preserved?

I am implementing a pause menu for my game in Android. If the activity pauses and then resume, It lose the OpenGl context. However if you use setPreserveEGLContextOnPause(true) it MAY preserve the ...
1
vote
3answers
625 views

OpenGL ES, orthographic projection and viewport

I want to make some simple 2D game on iOS to familiarize myself with OpenGL ES. I started with Ray Wenderlich’s tutorial (How To Create A Simple 2D iPhone Game with OpenGL ES 2.0 and GLKit). That ...
2
votes
1answer
68 views

Get Stencil buffer working iOS OpenGL ES 2.0

I have been trying to get this work but either get black screen or reporting error when using XCode to analyze the GL code like below. Any help appreciated. I am using Swift here if that making a ...
0
votes
3answers
8k views

2D Rendering with OpenGL ES 2.0 on Android (matrices not working)

So I'm trying to render two moving quads, each at different locations. My shaders are as simple as possible (vertices are only transformed by the modelview-projection matrix, there's only one color). ...
3
votes
0answers
56 views

Optimal batching for 2D objects with transparency

I have a collection of 2d objects with transparency. Each object has a depth value to determine draw order and a material. I'm trying to batch them in an optimal way to minimize draw calls. Assume ...
0
votes
1answer
69 views

How can I describe a square in OpenGL ES 2.0?

I need to draw a Tic-Tac-Toe board in Xcode using OpenGL ES 2.0. I am new to graphics programming and can't find good information on drawing a square in opengl es in iOS. I looked at Ray's tutorials, ...
3
votes
1answer
160 views

How do OpenGL ES 2 engines typically handle automatic geometry sorting and batching?

I'm trying to write a basic OpenGL ES 2 engine that can automatically sort and batch a fairly flexible set of input draw descriptions. When I say 'draw description' I mean the actual uniforms, state,...
-3
votes
1answer
25 views

OpenGL ES 2 inheriting issues [closed]

I am Having an issue where one of my classes will not inherit the other ones variable value. In the class which is inherited. It shows the value of the float just fine. But when I go to the Class ...
0
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0answers
28 views

Simple OpenGL ES 2 program fails

I'm stuck on a very simple OpenGL ES application from 2 days now. I am a "beginner" OpenGL developer, and this is my first attempt at the ES version on android. This is a VERY simple app, the usual ...
1
vote
0answers
73 views

how to temporarily turn off/on multisampling for an OpenGL ES 2.0 render context in Android?

In my OpenGL ES 2.0 Android app, I render to an EGL surface with >= 2 samples; I obtain this surface by passing: EGL14.EGL_SAMPLES, 2 as part of the attribute_list argument for egl.eglChooseconfig() ...
0
votes
2answers
293 views

libgdx texture edge blending problem

I have two completely white bitmaps here: They're there, trust me. When I put one on top of the other and scale them down with TextureFilter.Linear I get this: How do I get rid of the dark ...
0
votes
1answer
148 views

GLES2 rendering performance for different iPad generations

I'm using C++/GLES2 for iPad only (no iPhone). The only device I own is an iPad2 and I do not plan to support iPad 1. Can anyone help me understand realistic goals/limits on iPad 2/3/4 in terms of ...
1
vote
1answer
63 views

OpenGL ES 2.0 facet lighting

I am trying to figure out if there is a way to achieve facet lighting in OpenGL ES 2.0 without extensions. I know it is possible if I don't used indexed vertices but I don't really want to do that ...
1
vote
1answer
57 views

Effect of vertex winding on normals and shading

I have implemented a Phong and Gourand shader for a triangle mesh that is being imported from an STL file. It appears to be working fairly allright but some triangles seem to be what I can only ...
5
votes
1answer
356 views

Calculated normals for mesh not working

I am trying to implement a 3D mesh viewer with C++ and OpenGL ES 2. I am currently struggling with the calculation of the normals for the vertices, or at least I think that is where the problem lies......
1
vote
0answers
57 views

blending with OpenGL glBlendFunc and glBlendEquation

I want to draw a bunch of images in front of a background. Where images overlap, I want those to be blended together (for now, using a mix of 0.5 source * 0.5 destination color every time an image ...
1
vote
1answer
46 views

Rendering sprites on a Mali-400 MP device

I started developing a small cross platform game engine using OpenGL, I am working actually on a sprite batch renderer. Everything is working fine on OS X, iOS, Win32, and some Android Devices. Here ...
3
votes
1answer
164 views

How to deal with overlapping black parts of Light mask textures?

I am using this masking texture for a dynamic lighting effect in my game: It looks beautiful until two lights begin to overlap: This is obviously because the textures are overlapping when I draw ...
0
votes
1answer
68 views

drawing a horizon / sky in OpenGL ES 2.0

I want to render a sky: My camera is at the origin, and I want there to be a white background for all world coordinates with z < 0 (would normally be considered y > 0, but I have a different ...
0
votes
1answer
47 views

Opengles 2.0 multi Textures fade out one by one

I have multi textures, A was drawed on top of B, B was on top of C ...., ( like Picture 1) .I want to fade out A first, then B will appear and fade out either... But when A fade out, background color ...
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0answers
34 views

OpenGL ES 2.0: Highly variable time spent in GLES20.glDrawArrays(). How to find the cause?

How can I debug why the time take to issue exactly the same GL commands to render a frame, especially the call to GLES20.glDrawArrays(), is highly variable even when there is no garbage collection and ...
3
votes
0answers
39 views

When I add in Java transformationMatrix I can't see images? [closed]

When I add in Java transformationMatrix I can't see images moving but when I remove it I can see why and how to fix it? Any ideas how to fix it? My Renderer class: public class Renderer { ...
2
votes
0answers
93 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 ...
4
votes
1answer
70 views

Shaders: packing 4 textures into a single RGBA - slower?

I'm experiencing something really strange on an iOS mobile device. I have 4 textures, and after some profiling it seems, that doing four separate grayscale texture reads is faster, than reading the ...
2
votes
0answers
708 views

How to implement OpenGL triple buffering of buffer objects to avoid stalls?

I'm trying to implement the triple buffering described here. The intent is to gain higher frame rate by avoiding waiting for glBufferSubData() to finish. My understanding is that this is how to ...
2
votes
1answer
169 views

Stencil Buffer not working as expected in OpenGL ES 2.0 (Android)

I'm trying to get to grips with the stencil buffer. Apart from setting up viewport, camera, etc, my OpenGL ES 2.0 initialisation code is: GLES20.glDisable(GLES20.GL_CULL_FACE); GLES20.glDisable(...
6
votes
3answers
2k views

What is Khronos EGL?

I see that modern OpenGL related code uses EGL, i can't get good resources for this so i ask here: what exactly is EGL ? if a platform supports OpenGL ES 2.0+ or OpenGL 3.0+ i can presume that will ...
1
vote
2answers
298 views

Optimize drawing “different” sprites in OpenGL ES 2.0 (batching?)

I started experimenting with OpenGL ES 2.0, and I'm trying to figure out a way to optimize/batch sprite drawing, where sprites only have the texture in common, but differ in the following properties: ...
1
vote
0answers
126 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 ...
0
votes
0answers
23 views

OpenGL ES 2.0 save data for next render cycle

I'm currently writing a simple game, that should be able to cope with moving and rendering a large number of ships (particles). I started benchmarking with a sprite system, but obviously it was to ...
3
votes
1answer
93 views

Do shader compilers typically know not to look up unused texture channels?

I have a texture that's from the color attachment of an FBO in OpenGL ES 2.0, so I have limited control over the number of channels in the image. Suppose I only need the color from the R channel of ...
0
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0answers
32 views

OpenGL ES 2.0 + Cairo HUD

I have posted this on StackOverflow before finding this Q&A so please excuse the double post but I think there will be more experts in terms of OpenGL around here. I am trying to render a HUD ...
1
vote
1answer
610 views

GL_EXT_shadow_samplers killing my shader

I have the following fragment shader for my scene #extension GL_EXT_shadow_samplers : require ... vec4 color = texture2D(uTextureUnit0, varTexCoord0); if (colorTransformEnabled != 0) { vec3 ...
0
votes
1answer
310 views

Setting up a Visual Studio project for OpenGL and OpenGL ES

I want to make a small game with OpenGL and glew for desktop, android and web. So far I know how to set up a project for opengl and a project for opengl es but I would like to have the game source ...
0
votes
0answers
14 views

AndEngine : Collision does not make line disappear

I have drawn the line between two sprites and there is a rectangle. When the line collides with rectangle the line should be invisible else the line should be visible. But i am having problem with ...
0
votes
0answers
68 views

Opengl Create FBO- fatal signal 11 error

in my android game, i want to render My scene in the FBO and a texture attached to it, and use that texture later, But When i use glGenFramebuffers i get this error: 07-30 06:17:27.839: A/libc(1338): ...
2
votes
1answer
64 views

OpenGL ES God Ray Precision error

I have encountered the following (i think) precision error. (missing link need 10 rep) My source of inspiration was: (missing link need 10 rep) On the PC everything works fine, but on android it ...
0
votes
1answer
55 views

Best approach for level specific textures

TL;DR: Best way to handle level-specific textures without overkilling memory usage and killing performance and keeping things clean in OpenGL for mobile (also lower-end devices) and desktop using ...
0
votes
1answer
170 views

How to send dynamic data to a vertex shader OpenGL ES 2 Android

I'm very new to Android development and OpenGL ES 2.0. I have been working through a book called "OpenGL ES 2 for Android A Quick Start Guide" which has been useful, but at times I get a bit lost as ...
0
votes
1answer
2k views

Is ETC2 Texture Compression available in OpenGL ES 2.0?

I have an ES 2.0 app and would like to use ETC2 texture compression if it is available (i.e. I am running on a device that supports ES 3.0 standard). Is it possible to use ETC2 in ES 1.1/2.0, and if ...
0
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0answers
187 views

OpenGL - Make two images blend together

I have 2 images that are .png and they mix together, The problem is that one overwrite the other. I know that the draw order matters, but In that case I should redraw the icons 2 times ( there is a ...
0
votes
0answers
37 views

Issue with texture mapping on a spehre using opgengl es 2.0

I have a problem to calculate the right UV coordinates. I'm calculating the sphere by subdivate a ocathdron. What did I do wrong? Calculate UV Points for the texture: private List<Float>...
1
vote
1answer
74 views

How to debug a GLSL shader? [duplicate]

I cannot find any tutorial in Google and Youtube. I have a C++ program that uses OpenGL ES 2.0 API to render something on the screen. How can I debug my shaders? Any step-by-step guide? What is the ...
1
vote
1answer
468 views

Java Buffers and OpenGL ES 2.0 (Android)

I've been trying to come up with a good solution for preloading textures asynchronously, but in Android with OpenGL ES you cannot create a texture out of context. Would the proper solution be to load ...