i want to create a wrapping effect of the image as shown in the video ( http://www.youtube.com/watch?v=zy8YtRnX ... re=related ) but on a continues bases when it rolls and wraps itself.

i am using opengl es 2.0


this is the code i could do till now. can you i get help please. how to modify the vertex shaders


GLbyte vShaderStr[] =
// "uniform mat4 u_mvpMatrix; \n"

// "attribute vec4 a_position; \n"
// "uniform float u_time; \n"
"attribute vec2 a_texCoord; \n"
"attribute vec3 a_startPosition; \n"
"varying vec2 v_texCoord; \n"
// "varying float v_lifetime; \n"


"void main() \n"
"{ \n"
" gl_Position.xyz = a_startPosition.xyz; \n" //+ (u_time * a_endPosition);



" gl_Position.w =1; \n" //keep it one if u want translation




" v_texCoord =a_texCoord; \n"

"} \n";

GLbyte fShaderStr[] =
"precision mediump float; \n"
"varying vec2 v_texCoord; \n"

"uniform sampler2D s_baseMap; \n"

"void main() \n"
"{ \n"
" vec4 baseColor; \n"

" \n"
" baseColor = texture2D( s_baseMap, v_texCoord ); \n"

" gl_FragColor = baseColor ; \n"
"} \n";