~ubuntu-branches/ubuntu/utopic/blender/utopic-proposed

/*

 * Parts adapted from Open Shading Language with this license:

 *

 * Copyright (c) 2009-2010 Sony Pictures Imageworks Inc., et al.

 * All Rights Reserved.

 *

 * Modifications Copyright 2011, Blender Foundation.

 * 

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are

 * met:

 * * Redistributions of source code must retain the above copyright

 *   notice, this list of conditions and the following disclaimer.

 * * Redistributions in binary form must reproduce the above copyright

 *   notice, this list of conditions and the following disclaimer in the

 *   documentation and/or other materials provided with the distribution.

 * * Neither the name of Sony Pictures Imageworks nor the names of its

 *   contributors may be used to endorse or promote products derived from

 *   this software without specific prior written permission.

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#ifndef __KERNEL_PROJECTION_CL__

#define __KERNEL_PROJECTION_CL__

CCL_NAMESPACE_BEGIN

/* Spherical coordinates <-> Cartesian direction  */

__device float2 direction_to_spherical(float3 dir)

{

	float theta = acosf(dir.z);

	float phi = atan2f(dir.x, dir.y);

	return make_float2(theta, phi);

}

__device float3 spherical_to_direction(float theta, float phi)

{

	return make_float3(

		sinf(theta)*cosf(phi),

		sinf(theta)*sinf(phi),

		cosf(theta));

}

/* Equirectangular coordinates <-> Cartesian direction */

__device float2 direction_to_equirectangular(float3 dir)

{

	float u = -atan2f(dir.y, dir.x)/(M_2PI_F) + 0.5f;

	float v = atan2f(dir.z, hypotf(dir.x, dir.y))/M_PI_F + 0.5f;

	return make_float2(u, v);

}

__device float3 equirectangular_to_direction(float u, float v)

{

	float phi = M_PI_F*(1.0f - 2.0f*u);

	float theta = M_PI_F*(1.0f - v);

	return make_float3(

		sinf(theta)*cosf(phi),

		sinf(theta)*sinf(phi),

		cosf(theta));

}

/* Fisheye <-> Cartesian direction */

__device float2 direction_to_fisheye(float3 dir, float fov)

{

	float r = atan2f(sqrtf(dir.y*dir.y +  dir.z*dir.z), dir.x) / fov;

	float phi = atan2f(dir.z, dir.y);

	float u = r * cosf(phi) + 0.5f;

	float v = r * sinf(phi) + 0.5f;

	return make_float2(u, v);

}

__device float3 fisheye_to_direction(float u, float v, float fov)

{

	u = (u - 0.5f) * 2.0f;

	v = (v - 0.5f) * 2.0f;

	float r = sqrtf(u*u + v*v);

	if(r > 1.0f)

		return make_float3(0.0f, 0.0f, 0.0f);

	float phi = acosf((r != 0.0f)? u/r: 0.0f);

	float theta = r * fov * 0.5f;

	if(v < 0.0f) phi = -phi;

	return make_float3(

		 cosf(theta),

		 -cosf(phi)*sinf(theta),

		 sinf(phi)*sinf(theta)

	);

}

__device float2 direction_to_fisheye_equisolid(float3 dir, float lens, float width, float height)

{

	float theta = acosf(dir.x);

	float r = 2.0f * lens * sinf(theta * 0.5f);

	float phi = atan2f(dir.z, dir.y);

	float u = r * cosf(phi) / width + 0.5f;

	float v = r * sinf(phi) / height + 0.5f;

	return make_float2(u, v);

}

__device float3 fisheye_equisolid_to_direction(float u, float v, float lens, float fov, float width, float height)

{

	u = (u - 0.5f) * width;

	v = (v - 0.5f) * height;

	float rmax = 2.0f * lens * sinf(fov * 0.25f);

	float r = sqrtf(u*u + v*v);

	if(r > rmax)

		return make_float3(0.0f, 0.0f, 0.0f);

	float phi = acosf((r != 0.0f)? u/r: 0.0f);

	float theta = 2.0f * asinf(r/(2.0f * lens));

	if(v < 0.0f) phi = -phi;

	return make_float3(

		 cosf(theta),

		 -cosf(phi)*sinf(theta),

		 sinf(phi)*sinf(theta)

	);

}

/* Mirror Ball <-> Cartesion direction */

__device float3 mirrorball_to_direction(float u, float v)

{

	/* point on sphere */

	float3 dir;

	dir.x = 2.0f*u - 1.0f;

	dir.z = 2.0f*v - 1.0f;

	dir.y = -sqrtf(max(1.0f - dir.x*dir.x - dir.z*dir.z, 0.0f));

	/* reflection */

	float3 I = make_float3(0.0f, -1.0f, 0.0f);

	return 2.0f*dot(dir, I)*dir - I;

}

__device float2 direction_to_mirrorball(float3 dir)

{

	/* inverse of mirrorball_to_direction */

	dir.y -= 1.0f;

	float div = 2.0f*sqrtf(max(-0.5f*dir.y, 0.0f));

	if(div > 0.0f)

		dir /= div;

	float u = 0.5f*(dir.x + 1.0f);

	float v = 0.5f*(dir.z + 1.0f);

	return make_float2(u, v);

}

__device float3 panorama_to_direction(KernelGlobals *kg, float u, float v)

{

	switch(kernel_data.cam.panorama_type) {

		case PANORAMA_EQUIRECTANGULAR:

			return equirectangular_to_direction(u, v);

		case PANORAMA_FISHEYE_EQUIDISTANT:

			return fisheye_to_direction(u, v, kernel_data.cam.fisheye_fov);

		case PANORAMA_FISHEYE_EQUISOLID:

		default:

			return fisheye_equisolid_to_direction(u, v, kernel_data.cam.fisheye_lens,

				kernel_data.cam.fisheye_fov, kernel_data.cam.sensorwidth, kernel_data.cam.sensorheight);

	}

}

__device float2 direction_to_panorama(KernelGlobals *kg, float3 dir)

{

	switch(kernel_data.cam.panorama_type) {

		case PANORAMA_EQUIRECTANGULAR:

			return direction_to_equirectangular(dir);

		case PANORAMA_FISHEYE_EQUIDISTANT:

			return direction_to_fisheye(dir, kernel_data.cam.fisheye_fov);

		case PANORAMA_FISHEYE_EQUISOLID:

		default:

			return direction_to_fisheye_equisolid(dir, kernel_data.cam.fisheye_lens,

				kernel_data.cam.sensorwidth, kernel_data.cam.sensorheight);

	}

}

CCL_NAMESPACE_END

#endif /* __KERNEL_PROJECTION_CL__ */