/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/blenkernel/intern/camera.c
 *  \ingroup bke
 */

#include <stdlib.h>

#include "DNA_camera_types.h"
#include "DNA_lamp_types.h"
#include "DNA_object_types.h"
#include "DNA_scene_types.h"
#include "DNA_view3d_types.h"

#include "BLI_math.h"
#include "BLI_utildefines.h"

#include "BKE_animsys.h"
#include "BKE_camera.h"
#include "BKE_object.h"
#include "BKE_global.h"
#include "BKE_library.h"
#include "BKE_main.h"
#include "BKE_screen.h"

/****************************** Camera Datablock *****************************/

void *BKE_camera_add(Main *bmain, const char *name)
{
	Camera *cam;
	
	cam =  BKE_libblock_alloc(bmain, ID_CA, name);

	cam->lens = 35.0f;
	cam->sensor_x = DEFAULT_SENSOR_WIDTH;
	cam->sensor_y = DEFAULT_SENSOR_HEIGHT;
	cam->clipsta = 0.1f;
	cam->clipend = 100.0f;
	cam->drawsize = 0.5f;
	cam->ortho_scale = 6.0;
	cam->flag |= CAM_SHOWPASSEPARTOUT;
	cam->passepartalpha = 0.5f;
	
	return cam;
}

Camera *BKE_camera_copy(Camera *cam)
{
	Camera *camn;
	
	camn = BKE_libblock_copy(&cam->id);

	id_lib_extern((ID *)camn->dof_ob);

	return camn;
}

void BKE_camera_make_local(Camera *cam)
{
	Main *bmain = G.main;
	Object *ob;
	bool is_local = false, is_lib = false;

	/* - only lib users: do nothing
	 * - only local users: set flag
	 * - mixed: make copy
	 */
	
	if (cam->id.lib == NULL) return;
	if (cam->id.us == 1) {
		id_clear_lib_data(bmain, &cam->id);
		return;
	}
	
	for (ob = bmain->object.first; ob && ELEM(0, is_lib, is_local); ob = ob->id.next) {
		if (ob->data == cam) {
			if (ob->id.lib) is_lib = true;
			else is_local = true;
		}
	}
	
	if (is_local && is_lib == false) {
		id_clear_lib_data(bmain, &cam->id);
	}
	else if (is_local && is_lib) {
		Camera *cam_new = BKE_camera_copy(cam);

		cam_new->id.us = 0;

		/* Remap paths of new ID using old library as base. */
		BKE_id_lib_local_paths(bmain, cam->id.lib, &cam_new->id);

		for (ob = bmain->object.first; ob; ob = ob->id.next) {
			if (ob->data == cam) {
				if (ob->id.lib == NULL) {
					ob->data = cam_new;
					cam_new->id.us++;
					cam->id.us--;
				}
			}
		}
	}
}

void BKE_camera_free(Camera *ca)
{
	BKE_free_animdata((ID *)ca);
}

/******************************** Camera Usage *******************************/

void BKE_camera_object_mode(RenderData *rd, Object *cam_ob)
{
	rd->mode &= ~(R_ORTHO | R_PANORAMA);

	if (cam_ob && cam_ob->type == OB_CAMERA) {
		Camera *cam = cam_ob->data;
		if (cam->type == CAM_ORTHO) rd->mode |= R_ORTHO;
		if (cam->type == CAM_PANO) rd->mode |= R_PANORAMA;
	}
}

/* get the camera's dof value, takes the dof object into account */
float BKE_camera_object_dof_distance(Object *ob)
{
	Camera *cam = (Camera *)ob->data; 
	if (ob->type != OB_CAMERA)
		return 0.0f;
	if (cam->dof_ob) {
		/* too simple, better to return the distance on the view axis only
		 * return len_v3v3(ob->obmat[3], cam->dof_ob->obmat[3]); */
		float mat[4][4], imat[4][4], obmat[4][4];
		
		copy_m4_m4(obmat, ob->obmat);
		normalize_m4(obmat);
		invert_m4_m4(imat, obmat);
		mul_m4_m4m4(mat, imat, cam->dof_ob->obmat);
		return fabsf(mat[3][2]);
	}
	return cam->YF_dofdist;
}

float BKE_camera_sensor_size(int sensor_fit, float sensor_x, float sensor_y)
{
	/* sensor size used to fit to. for auto, sensor_x is both x and y. */
	if (sensor_fit == CAMERA_SENSOR_FIT_VERT)
		return sensor_y;

	return sensor_x;
}

int BKE_camera_sensor_fit(int sensor_fit, float sizex, float sizey)
{
	if (sensor_fit == CAMERA_SENSOR_FIT_AUTO) {
		if (sizex >= sizey)
			return CAMERA_SENSOR_FIT_HOR;
		else
			return CAMERA_SENSOR_FIT_VERT;
	}

	return sensor_fit;
}

/******************************** Camera Params *******************************/

void BKE_camera_params_init(CameraParams *params)
{
	memset(params, 0, sizeof(CameraParams));

	/* defaults */
	params->sensor_x = DEFAULT_SENSOR_WIDTH;
	params->sensor_y = DEFAULT_SENSOR_HEIGHT;
	params->sensor_fit = CAMERA_SENSOR_FIT_AUTO;

	params->zoom = 1.0f;

	/* fallback for non camera objects */
	params->clipsta = 0.1f;
	params->clipsta = 100.0f;
}

void BKE_camera_params_from_object(CameraParams *params, Object *ob)
{
	if (!ob)
		return;

	if (ob->type == OB_CAMERA) {
		/* camera object */
		Camera *cam = ob->data;

		if (cam->type == CAM_ORTHO)
			params->is_ortho = true;
		params->lens = cam->lens;
		params->ortho_scale = cam->ortho_scale;

		params->shiftx = cam->shiftx;
		params->shifty = cam->shifty;

		params->sensor_x = cam->sensor_x;
		params->sensor_y = cam->sensor_y;
		params->sensor_fit = cam->sensor_fit;

		params->clipsta = cam->clipsta;
		params->clipend = cam->clipend;
	}
	else if (ob->type == OB_LAMP) {
		/* lamp object */
		Lamp *la = ob->data;
		float fac = cosf(la->spotsize * 0.5f);
		float phi = acos(fac);

		params->lens = 16.0f * fac / sinf(phi);
		if (params->lens == 0.0f)
			params->lens = 35.0f;

		params->clipsta = la->clipsta;
		params->clipend = la->clipend;
	}
	else {
		params->lens = 35.0f;
	}
}

void BKE_camera_params_from_view3d(CameraParams *params, View3D *v3d, RegionView3D *rv3d)
{
	/* common */
	params->lens = v3d->lens;
	params->clipsta = v3d->near;
	params->clipend = v3d->far;

	if (rv3d->persp == RV3D_CAMOB) {
		/* camera view */
		BKE_camera_params_from_object(params, v3d->camera);

		params->zoom = BKE_screen_view3d_zoom_to_fac((float)rv3d->camzoom);

		params->offsetx = 2.0f * rv3d->camdx * params->zoom;
		params->offsety = 2.0f * rv3d->camdy * params->zoom;

		params->shiftx *= params->zoom;
		params->shifty *= params->zoom;

		params->zoom = 1.0f / params->zoom;
	}
	else if (rv3d->persp == RV3D_ORTHO) {
		/* orthographic view */
		int sensor_size = BKE_camera_sensor_size(params->sensor_fit, params->sensor_x, params->sensor_y);
		params->clipend *= 0.5f;    // otherwise too extreme low zbuffer quality
		params->clipsta = -params->clipend;

		params->is_ortho = true;
		/* make sure any changes to this match ED_view3d_radius_to_ortho_dist() */
		params->ortho_scale = rv3d->dist * sensor_size / v3d->lens;
		params->zoom = 2.0f;
	}
	else {
		/* perspective view */
		params->zoom = 2.0f;
	}
}

void BKE_camera_params_compute_viewplane(CameraParams *params, int winx, int winy, float xasp, float yasp)
{
	rctf viewplane;
	float pixsize, viewfac, sensor_size, dx, dy;
	int sensor_fit;

	/* fields rendering */
	params->ycor = yasp / xasp;
	if (params->use_fields)
		params->ycor *= 2.0f;

	if (params->is_ortho) {
		/* orthographic camera */
		/* scale == 1.0 means exact 1 to 1 mapping */
		pixsize = params->ortho_scale;
	}
	else {
		/* perspective camera */
		sensor_size = BKE_camera_sensor_size(params->sensor_fit, params->sensor_x, params->sensor_y);
		pixsize = (sensor_size * params->clipsta) / params->lens;
	}

	/* determine sensor fit */
	sensor_fit = BKE_camera_sensor_fit(params->sensor_fit, xasp * winx, yasp * winy);

	if (sensor_fit == CAMERA_SENSOR_FIT_HOR)
		viewfac = winx;
	else
		viewfac = params->ycor * winy;

	pixsize /= viewfac;

	/* extra zoom factor */
	pixsize *= params->zoom;

	/* compute view plane:
	 * fully centered, zbuffer fills in jittered between -.5 and +.5 */
	viewplane.xmin = -0.5f * (float)winx;
	viewplane.ymin = -0.5f * params->ycor * (float)winy;
	viewplane.xmax =  0.5f * (float)winx;
	viewplane.ymax =  0.5f * params->ycor * (float)winy;

	/* lens shift and offset */
	dx = params->shiftx * viewfac + winx * params->offsetx;
	dy = params->shifty * viewfac + winy * params->offsety;

	viewplane.xmin += dx;
	viewplane.ymin += dy;
	viewplane.xmax += dx;
	viewplane.ymax += dy;

	/* fields offset */
	if (params->field_second) {
		if (params->field_odd) {
			viewplane.ymin -= 0.5f * params->ycor;
			viewplane.ymax -= 0.5f * params->ycor;
		}
		else {
			viewplane.ymin += 0.5f * params->ycor;
			viewplane.ymax += 0.5f * params->ycor;
		}
	}

	/* the window matrix is used for clipping, and not changed during OSA steps */
	/* using an offset of +0.5 here would give clip errors on edges */
	viewplane.xmin *= pixsize;
	viewplane.xmax *= pixsize;
	viewplane.ymin *= pixsize;
	viewplane.ymax *= pixsize;

	params->viewdx = pixsize;
	params->viewdy = params->ycor * pixsize;
	params->viewplane = viewplane;
}

/* viewplane is assumed to be already computed */
void BKE_camera_params_compute_matrix(CameraParams *params)
{
	rctf viewplane = params->viewplane;

	/* compute projection matrix */
	if (params->is_ortho)
		orthographic_m4(params->winmat, viewplane.xmin, viewplane.xmax,
		                viewplane.ymin, viewplane.ymax, params->clipsta, params->clipend);
	else
		perspective_m4(params->winmat, viewplane.xmin, viewplane.xmax,
		               viewplane.ymin, viewplane.ymax, params->clipsta, params->clipend);
}

/***************************** Camera View Frame *****************************/

void BKE_camera_view_frame_ex(Scene *scene, Camera *camera, float drawsize, const bool do_clip, const float scale[3],
                              float r_asp[2], float r_shift[2], float *r_drawsize, float r_vec[4][3])
{
	float facx, facy;
	float depth;

	/* aspect correcton */
	if (scene) {
		float aspx = (float) scene->r.xsch * scene->r.xasp;
		float aspy = (float) scene->r.ysch * scene->r.yasp;
		int sensor_fit = BKE_camera_sensor_fit(camera->sensor_fit, aspx, aspy);

		if (sensor_fit == CAMERA_SENSOR_FIT_HOR) {
			r_asp[0] = 1.0;
			r_asp[1] = aspy / aspx;
		}
		else {
			r_asp[0] = aspx / aspy;
			r_asp[1] = 1.0;
		}
	}
	else {
		r_asp[0] = 1.0f;
		r_asp[1] = 1.0f;
	}

	if (camera->type == CAM_ORTHO) {
		facx = 0.5f * camera->ortho_scale * r_asp[0] * scale[0];
		facy = 0.5f * camera->ortho_scale * r_asp[1] * scale[1];
		r_shift[0] = camera->shiftx * camera->ortho_scale * scale[0];
		r_shift[1] = camera->shifty * camera->ortho_scale * scale[1];
		depth = do_clip ? -((camera->clipsta * scale[2]) + 0.1f) : -drawsize * camera->ortho_scale * scale[2];

		*r_drawsize = 0.5f * camera->ortho_scale;
	}
	else {
		/* that way it's always visible - clipsta+0.1 */
		float fac, scale_x, scale_y;
		float half_sensor = 0.5f * ((camera->sensor_fit == CAMERA_SENSOR_FIT_VERT) ?
		                            (camera->sensor_y) : (camera->sensor_x));


		if (do_clip) {
			/* fixed depth, variable size (avoids exceeding clipping range) */
			/* r_drawsize shouldn't be used in this case, set to dummy value */
			*r_drawsize = 1.0f;
			depth = -(camera->clipsta + 0.1f) * scale[2];
			fac = depth / (camera->lens / (-half_sensor));
			scale_x = 1.0f;
			scale_y = 1.0f;
		}
		else {
			/* fixed size, variable depth (stays a reasonable size in the 3D view) */
			*r_drawsize = drawsize / ((scale[0] + scale[1] + scale[2]) / 3.0f);
			depth = *r_drawsize * camera->lens / (-half_sensor) * scale[2];
			fac = *r_drawsize;
			scale_x = scale[0];
			scale_y = scale[1];
		}

		facx = fac * r_asp[0] * scale_x;
		facy = fac * r_asp[1] * scale_y;
		r_shift[0] = camera->shiftx * fac * 2.0f * scale_x;
		r_shift[1] = camera->shifty * fac * 2.0f * scale_y;
	}

	r_vec[0][0] = r_shift[0] + facx; r_vec[0][1] = r_shift[1] + facy; r_vec[0][2] = depth;
	r_vec[1][0] = r_shift[0] + facx; r_vec[1][1] = r_shift[1] - facy; r_vec[1][2] = depth;
	r_vec[2][0] = r_shift[0] - facx; r_vec[2][1] = r_shift[1] - facy; r_vec[2][2] = depth;
	r_vec[3][0] = r_shift[0] - facx; r_vec[3][1] = r_shift[1] + facy; r_vec[3][2] = depth;
}

void BKE_camera_view_frame(Scene *scene, Camera *camera, float r_vec[4][3])
{
	float dummy_asp[2];
	float dummy_shift[2];
	float dummy_drawsize;
	const float dummy_scale[3] = {1.0f, 1.0f, 1.0f};

	BKE_camera_view_frame_ex(scene, camera, false, 1.0, dummy_scale,
	                         dummy_asp, dummy_shift, &dummy_drawsize, r_vec);
}


typedef struct CameraViewFrameData {
	float plane_tx[4][4];  /* 4 planes (not 4x4 matrix)*/
	float frame_tx[4][3];
	float normal_tx[4][3];
	float dist_vals_sq[4];  /* distance squared (signed) */
	unsigned int tot;
} CameraViewFrameData;

static void camera_to_frame_view_cb(const float co[3], void *user_data)
{
	CameraViewFrameData *data = (CameraViewFrameData *)user_data;
	unsigned int i;

	for (i = 0; i < 4; i++) {
		float nd = dist_squared_to_plane_v3(co, data->plane_tx[i]);
		if (nd < data->dist_vals_sq[i]) {
			data->dist_vals_sq[i] = nd;
		}
	}

	data->tot++;
}

/* don't move the camera, just yield the fit location */
/* only valid for perspective cameras */
bool BKE_camera_view_frame_fit_to_scene(Scene *scene, struct View3D *v3d, Object *camera_ob, float r_co[3])
{
	float shift[2];
	float plane_tx[4][3];
	float rot_obmat[3][3];
	const float zero[3] = {0, 0, 0};
	CameraViewFrameData data_cb;

	unsigned int i;

	BKE_camera_view_frame(scene, camera_ob->data, data_cb.frame_tx);

	copy_m3_m4(rot_obmat, camera_ob->obmat);
	normalize_m3(rot_obmat);

	for (i = 0; i < 4; i++) {
		/* normalize so Z is always 1.0f*/
		mul_v3_fl(data_cb.frame_tx[i], 1.0f / data_cb.frame_tx[i][2]);
	}

	/* get the shift back out of the frame */
	shift[0] = (data_cb.frame_tx[0][0] +
	            data_cb.frame_tx[1][0] +
	            data_cb.frame_tx[2][0] +
	            data_cb.frame_tx[3][0]) / 4.0f;
	shift[1] = (data_cb.frame_tx[0][1] +
	            data_cb.frame_tx[1][1] +
	            data_cb.frame_tx[2][1] +
	            data_cb.frame_tx[3][1]) / 4.0f;

	for (i = 0; i < 4; i++) {
		mul_m3_v3(rot_obmat, data_cb.frame_tx[i]);
	}

	for (i = 0; i < 4; i++) {
		normal_tri_v3(data_cb.normal_tx[i], zero, data_cb.frame_tx[i], data_cb.frame_tx[(i + 1) % 4]);
		plane_from_point_normal_v3(data_cb.plane_tx[i], data_cb.frame_tx[i], data_cb.normal_tx[i]);
	}

	/* initialize callback data */
	copy_v4_fl(data_cb.dist_vals_sq, FLT_MAX);
	data_cb.tot = 0;
	/* run callback on all visible points */
	BKE_scene_foreach_display_point(scene, v3d, BA_SELECT,
	                                camera_to_frame_view_cb, &data_cb);

	if (data_cb.tot <= 1) {
		return false;
	}
	else {
		float plane_isect_1[3], plane_isect_1_no[3], plane_isect_1_other[3];
		float plane_isect_2[3], plane_isect_2_no[3], plane_isect_2_other[3];

		float plane_isect_pt_1[3], plane_isect_pt_2[3];

		/* apply the dist-from-plane's to the transformed plane points */
		for (i = 0; i < 4; i++) {
			mul_v3_v3fl(plane_tx[i], data_cb.normal_tx[i], sqrtf_signed(data_cb.dist_vals_sq[i]));
		}

		if ((!isect_plane_plane_v3(plane_isect_1, plane_isect_1_no,
		                           plane_tx[0], data_cb.normal_tx[0],
		                           plane_tx[2], data_cb.normal_tx[2])) ||
		    (!isect_plane_plane_v3(plane_isect_2, plane_isect_2_no,
		                           plane_tx[1], data_cb.normal_tx[1],
		                           plane_tx[3], data_cb.normal_tx[3])))
		{
			return false;
		}

		add_v3_v3v3(plane_isect_1_other, plane_isect_1, plane_isect_1_no);
		add_v3_v3v3(plane_isect_2_other, plane_isect_2, plane_isect_2_no);

		if (isect_line_line_v3(plane_isect_1, plane_isect_1_other,
		                       plane_isect_2, plane_isect_2_other,
		                       plane_isect_pt_1, plane_isect_pt_2) == 0)
		{
			return false;
		}
		else {
			float cam_plane_no[3] = {0.0f, 0.0f, -1.0f};
			float plane_isect_delta[3];
			float plane_isect_delta_len;

			mul_m3_v3(rot_obmat, cam_plane_no);

			sub_v3_v3v3(plane_isect_delta, plane_isect_pt_2, plane_isect_pt_1);
			plane_isect_delta_len = len_v3(plane_isect_delta);

			if (dot_v3v3(plane_isect_delta, cam_plane_no) > 0.0f) {
				copy_v3_v3(r_co, plane_isect_pt_1);

				/* offset shift */
				normalize_v3(plane_isect_1_no);
				madd_v3_v3fl(r_co, plane_isect_1_no, shift[1] * -plane_isect_delta_len);
			}
			else {
				copy_v3_v3(r_co, plane_isect_pt_2);

				/* offset shift */
				normalize_v3(plane_isect_2_no);
				madd_v3_v3fl(r_co, plane_isect_2_no, shift[0] * -plane_isect_delta_len);
			}


			return true;
		}
	}
}
