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0
votes
1answer
258 views

Using OpenGL ES to do texture mapping on simple polygons?

Intro: I'm brand new at OpenGL. I first go familiar with texture mapping and basic transformations/translations on OpenGL on my PC. Now it seems I'm basically re-learning everything as im trying to ...
-2
votes
1answer
185 views

OpenGL ES 2. Texture mapping to a quad (not square or rect)?

http://smotr.im/9KwB There are some pictures: 1)a texture I have 2)a line I have already drawed with triangle strip 3)the result I need to achieve The question is how to draw a texture inside these ...
0
votes
1answer
154 views

iPhone OpenGL ES1 VBO Texture Coordinate Issues

I switched my code to use VBO and suddenly my sprites (2 triangle triangle-strip) have bad texture coordinates. Disabling VBO makes the problem go away. Note - I align my vertex and texture ...
0
votes
1answer
706 views

iphone opengl es 2.0 non power of two

I thought the image file size doesn't have to be power of two in 2.0 but when I tried, it just showed black screen. But it works fine with power of two images. Can anyone give me some hint what I am ...
3
votes
1answer
566 views

OpenGL ES 2.0 texture distortion on large geometry GL_REPEAT

OpenGL ES 2.0 has serious precision issues with texture sampling - I've seen topics with a similar problem, but I haven't seen a real solution to this "distorted OpenGL ES 2.0 texture" problem yet. ...
2
votes
1answer
472 views

Imitate Polygon Stipple with OpenGL ES on iOS

I want to fill a concave polygon with a simple repeating pattern. I can already draw the polygon properly, unfortunately I am having problems with filling it. In OpenGL I could do this easily with ...
0
votes
0answers
473 views

uv mapping openglES

I am new to openGL and am trying to map a png global map around a sphere in opengl ES (iphone). I generated my uv coordinates with the following formula found in wikipedia, with a few changes in order ...
0
votes
0answers
462 views

iPhone OpenGL ES background texture problems

I am trying to set a .png file as my background in OpenGL, with the hopes of drawing more objects on top of it. I have an image that is a 320x480 RGB image. I setup my vertices, as follows: - ...
1
vote
1answer
345 views

white screen on mapping second texture on the back side of OpenGLES view

What I am trying to get is a flip animation where the front face is an album thumbnail and it rotates and scales to a larger Image showing album details. I am able to map the front texture from ...
2
votes
2answers
1k views

OpenGL ES Tiled Texture Mipmap problem - iPad/iPhone

I'm running into the traditional tile/mipmap problem on the iPad using OpenGL ES. Basically, if you have a large texture (larger than 1k X 1k), you can break it up into pieces and map those pieces ...
1
vote
2answers
936 views

mapping a texture on a square: Why is the image rotated?

I successfully mapped an image on a square in OpenGL ES...but its rotated 90 degrees. Im pretty new at OpenGL ES, and was wondering if someone could point out why exactly its rotated. Thanks! package ...
2
votes
1answer
249 views

is it possible to map multiple textures onto a shape in openGL ES?

Im new to OpenGL ES and wanted to create a bunch of triangles that would represent a grid of squares that i could map map tiles to. Is it possible to map separate textures on the same shape in OpenGL ...
1
vote
1answer
409 views

OpenGL ES for iPhone blending not working

I'm a beginner to 3D graphics in general and I'm trying to make a 3D game for the iPhone, and more specifically, to use textures that contain transparency. I am able to load a texture (an 8 bit .png ...
2
votes
1answer
1k views

Mapping textures to a sphere OpenGL ES

Right i am just getting into OpenGL ES, and if i am honest it is very daunting. Just need a little guidance to point me in the right direction for my current challenge. I have some code that ...
1
vote
0answers
400 views

Strange Problem with Skybox texture size - iPad, OGL Es 2.0

I'm new to the iPad dev. platform and currently making a terrain roamer demo with OpenGL Es 2.0. While implementing the skydome, I ran into a really strange problem that I could not solve. Skydome ...
3
votes
5answers
2k views

Mapping irregular shapes or other polygons (cartoons, sprites) to triangles in OpenGL ES

I don't understand the concept of showing sprites mapped into OpenGL Triangles. If OpenGL ES only draws triangles and points, How do you display/map non-triangular shapes? Why would a shape mapped ...
0
votes
2answers
902 views

iPhone, how do you draw from a texturepage using coregraphics?

I'm trying to work out how to draw from a TexturePage using CoreGraphics. Given a texture page (CGImageRef) which contains multiple 64x64 packed textures, how do I render sub areas from that page ...
2
votes
2answers
3k views

iPhone camera images as OpenGL ES textures

Is it possible to use an image captured with the iPhone's camera as a texture that is then manipulated in OpenGL ES (flag wave effect, etc.)? The main problem being the size of the iPhone screen ...