try this in the shader code of this link: http://notlion.github.com/streetview-stereographic/#o=0.409,-0.207,0.681,0.571&z=1.553&mz=15&p=22.27844,114.16438

gistfile1.txt

uniform sampler2D texture;
uniform float scale, aspect, time;
uniform mat3 transform;

varying vec2 v_texcoord;

#define PI   3.141592653589793
#define PI_2 1.570796326794897

 vec2 tc_offset[9];

void main(){
    int doEdge = 1;

    vec2 rads = vec2(PI * 2., PI);
    float x = (v_texcoord.x - .5) * scale;
    float y = (v_texcoord.y - .5) * scale * aspect;

    // Project to Sphere
    vec3 sphere_pnt = vec3(
        (2. * x) / (1. + x*x + y*y),
        (2. * y) / (1. + x*x + y*y),
        (x*x + y*y - 1.) / (1. + x*x + y*y)
    );
    sphere_pnt *= transform;

    // Convert to Spherical Coordinates
    float r = length(sphere_pnt);
    float lon = atan(sphere_pnt.y, sphere_pnt.x);
    float lat = acos(sphere_pnt.z / r);

	if( doEdge == 1 ){
		
		vec4 sample[9];
		tc_offset[0] = vec2(-1.0, -1.0);
		tc_offset[1] = vec2(0.0, -1.0);
		tc_offset[2] = vec2(1.0, -1.0);
		tc_offset[3] = vec2(-1.0, 0.0);
		tc_offset[4] = vec2(0.0, 0.0);
		tc_offset[5] = vec2(1.0, 0.0);
		tc_offset[6] = vec2(-1.0, 1.0);
		tc_offset[7] = vec2(0.0, 1.0);
		tc_offset[8] = vec2(1.0, 1.0);
		
		//color2 = texture2D(texture, vec2(lon, lat) / rads);


		for(int i = 0; i < 9; i++){
		    sample[i] = texture2D(texture, (vec2(lon, lat) / rads) + tc_offset[i] * 0.001);
		}
		
		vec4 horizEdge = sample[2] + (2.0*sample[5]) + sample[8] -
				 (sample[0] + (2.0*sample[3]) + sample[6]);

		vec4 vertEdge = sample[0] + (2.0*sample[1]) + sample[2] -
						(sample[6] + (2.0*sample[7]) + sample[8]);

		vec3 s3 = sqrt((horizEdge.rgb * horizEdge.rgb) + (vertEdge.rgb * vertEdge.rgb));
		float brightness = (s3.r + s3.g + s3.b) / 3.0;
		
		if( brightness > 0.35 ){
			brightness = 0.0;
		}else{
			brightness = 1.0;
		}
                
                vec4 color = texture2D(texture, vec2(lon, lat) / rads);
                color.rgb *= brightness; 
                gl_FragColor = color;

	}



}

Made an issue so I don't forget later..
notlion/streetview-stereographic#1

haha - the proper way to do it :)

…

On Jan 9, 2012, at 3:37 PM, Ryan Alexander wrote: Made an issue so I don't forget later.. notlion/streetview-stereographic#1 --- Reply to this email directly or view it on GitHub: https://gist.github.com/1566967