fsh
#ifdef GL_ES
precision mediump float;
#endif
varying vec4 v_fragmentColor;
varying vec2 v_texCoord;
float angle(vec2 center, vec2 point)
{
float angle = atan( (center.y - point.y) , (center.x - point.x) );
angle = (angle >= 0.0) ? angle : 2.0 * 3.141592654 + angle;
float singlePice = 360.0 / (3.141592654 * 2.0);
return angle * singlePice;
}
float getColorWidget(float angle, float max, float min)
{
float widget = 0.0;
float _angle = angle - min;
float _max = max - min;
float _min = 0.0;
float middle = _max * 0.5;
if (_angle > _min && _angle <= _max)
widget = ( _angle > middle ? _max - _angle : _angle ) / middle;
return widget;
}
void main()
{
vec4 sum = texture2D(CC_Texture0, v_texCoord);
float angle = angle(vec2(0.5, 0.5), vec2( v_texCoord.x, v_texCoord.y ));
vec2 cord = vec2( abs( 0.5 - v_texCoord.x ), abs( 0.5 - v_texCoord.y)