/*
 * ***** 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) 2005 Blender Foundation.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL/BL DUAL LICENSE BLOCK *****
 */

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


#include <string.h>
#include <math.h>
#include <stdlib.h>
#include <float.h>

#include "MEM_guardedalloc.h"

#include "DNA_color_types.h"
#include "DNA_curve_types.h"

#include "BLI_blenlib.h"
#include "BLI_math.h"
#include "BLI_utildefines.h"
#include "BLI_task.h"
#include "BLI_threads.h"

#include "BKE_colortools.h"
#include "BKE_curve.h"
#include "BKE_fcurve.h"


#include "IMB_colormanagement.h"
#include "IMB_imbuf_types.h"

/* ********************************* color curve ********************* */

/* ***************** operations on full struct ************* */

void curvemapping_set_defaults(CurveMapping *cumap, int tot, float minx, float miny, float maxx, float maxy)
{
	int a;
	float clipminx, clipminy, clipmaxx, clipmaxy;
	
	cumap->flag = CUMA_DO_CLIP;
	if (tot == 4) cumap->cur = 3;   /* rhms, hack for 'col' curve? */
	
	clipminx = min_ff(minx, maxx);
	clipminy = min_ff(miny, maxy);
	clipmaxx = max_ff(minx, maxx);
	clipmaxy = max_ff(miny, maxy);
	
	BLI_rctf_init(&cumap->curr, clipminx, clipmaxx, clipminy, clipmaxy);
	cumap->clipr = cumap->curr;
	
	cumap->white[0] = cumap->white[1] = cumap->white[2] = 1.0f;
	cumap->bwmul[0] = cumap->bwmul[1] = cumap->bwmul[2] = 1.0f;
	
	for (a = 0; a < tot; a++) {
		cumap->cm[a].flag = CUMA_EXTEND_EXTRAPOLATE;
		cumap->cm[a].totpoint = 2;
		cumap->cm[a].curve = MEM_callocN(2 * sizeof(CurveMapPoint), "curve points");

		cumap->cm[a].curve[0].x = minx;
		cumap->cm[a].curve[0].y = miny;
		cumap->cm[a].curve[1].x = maxx;
		cumap->cm[a].curve[1].y = maxy;
	}

	cumap->changed_timestamp = 0;
}

CurveMapping *curvemapping_add(int tot, float minx, float miny, float maxx, float maxy)
{
	CurveMapping *cumap;

	cumap = MEM_callocN(sizeof(CurveMapping), "new curvemap");

	curvemapping_set_defaults(cumap, tot, minx, miny, maxx, maxy);

	return cumap;
}

void curvemapping_free_data(CurveMapping *cumap)
{
	int a;

	for (a = 0; a < CM_TOT; a++) {
		if (cumap->cm[a].curve) {
			MEM_freeN(cumap->cm[a].curve);
			cumap->cm[a].curve = NULL;
		}
		if (cumap->cm[a].table) {
			MEM_freeN(cumap->cm[a].table);
			cumap->cm[a].table = NULL;
		}
		if (cumap->cm[a].premultable) {
			MEM_freeN(cumap->cm[a].premultable);
			cumap->cm[a].premultable = NULL;
		}
	}
}

void curvemapping_free(CurveMapping *cumap)
{
	if (cumap) {
		curvemapping_free_data(cumap);
		MEM_freeN(cumap);
	}
}

void curvemapping_copy_data(CurveMapping *target, const CurveMapping *cumap)
{
	int a;

	*target = *cumap;

	for (a = 0; a < CM_TOT; a++) {
		if (cumap->cm[a].curve)
			target->cm[a].curve = MEM_dupallocN(cumap->cm[a].curve);
		if (cumap->cm[a].table)
			target->cm[a].table = MEM_dupallocN(cumap->cm[a].table);
		if (cumap->cm[a].premultable)
			target->cm[a].premultable = MEM_dupallocN(cumap->cm[a].premultable);
	}
}

CurveMapping *curvemapping_copy(const CurveMapping *cumap)
{
	if (cumap) {
		CurveMapping *cumapn = MEM_dupallocN(cumap);
		curvemapping_copy_data(cumapn, cumap);
		return cumapn;
	}
	return NULL;
}

void curvemapping_set_black_white_ex(const float black[3], const float white[3], float r_bwmul[3])
{
	int a;

	for (a = 0; a < 3; a++) {
		const float delta = max_ff(white[a] - black[a], 1e-5f);
		r_bwmul[a] = 1.0f / delta;
	}
}

void curvemapping_set_black_white(CurveMapping *cumap, const float black[3], const float white[3])
{
	if (white) {
		copy_v3_v3(cumap->white, white);
	}
	if (black) {
		copy_v3_v3(cumap->black, black);
	}

	curvemapping_set_black_white_ex(cumap->black, cumap->white, cumap->bwmul);
	cumap->changed_timestamp++;
}

/* ***************** operations on single curve ************* */
/* ********** NOTE: requires curvemapping_changed() call after ******** */

/* remove specified point */
bool curvemap_remove_point(CurveMap *cuma, CurveMapPoint *point)
{
	CurveMapPoint *cmp;
	int a, b, removed = 0;
	
	/* must have 2 points minimum */
	if (cuma->totpoint <= 2)
		return false;

	cmp = MEM_mallocN((cuma->totpoint) * sizeof(CurveMapPoint), "curve points");

	/* well, lets keep the two outer points! */
	for (a = 0, b = 0; a < cuma->totpoint; a++) {
		if (&cuma->curve[a] != point) {
			cmp[b] = cuma->curve[a];
			b++;
		}
		else {
			removed++;
		}
	}
	
	MEM_freeN(cuma->curve);
	cuma->curve = cmp;
	cuma->totpoint -= removed;
	return (removed != 0);
}

/* removes with flag set */
void curvemap_remove(CurveMap *cuma, const short flag)
{
	CurveMapPoint *cmp = MEM_mallocN((cuma->totpoint) * sizeof(CurveMapPoint), "curve points");
	int a, b, removed = 0;
	
	/* well, lets keep the two outer points! */
	cmp[0] = cuma->curve[0];
	for (a = 1, b = 1; a < cuma->totpoint - 1; a++) {
		if (!(cuma->curve[a].flag & flag)) {
			cmp[b] = cuma->curve[a];
			b++;
		}
		else {
			removed++;
		}
	}
	cmp[b] = cuma->curve[a];
	
	MEM_freeN(cuma->curve);
	cuma->curve = cmp;
	cuma->totpoint -= removed;
}

CurveMapPoint *curvemap_insert(CurveMap *cuma, float x, float y)
{
	CurveMapPoint *cmp = MEM_callocN((cuma->totpoint + 1) * sizeof(CurveMapPoint), "curve points");
	CurveMapPoint *newcmp = NULL;
	int a, b;
	bool foundloc = false;

	/* insert fragments of the old one and the new point to the new curve */
	cuma->totpoint++;
	for (a = 0, b = 0; a < cuma->totpoint; a++) {
		if ((foundloc == false) && ((a + 1 == cuma->totpoint) || (x < cuma->curve[a].x))) {
			cmp[a].x = x;
			cmp[a].y = y;
			cmp[a].flag = CUMA_SELECT;
			foundloc = true;
			newcmp = &cmp[a];
		}
		else {
			cmp[a].x = cuma->curve[b].x;
			cmp[a].y = cuma->curve[b].y;
			/* make sure old points don't remain selected */
			cmp[a].flag = cuma->curve[b].flag & ~CUMA_SELECT;
			cmp[a].shorty = cuma->curve[b].shorty;
			b++;
		}
	}

	/* free old curve and replace it with new one */
	MEM_freeN(cuma->curve);
	cuma->curve = cmp;

	return newcmp;
}

void curvemap_reset(CurveMap *cuma, const rctf *clipr, int preset, int slope)
{
	if (cuma->curve)
		MEM_freeN(cuma->curve);

	switch (preset) {
		case CURVE_PRESET_LINE: cuma->totpoint = 2; break;
		case CURVE_PRESET_SHARP: cuma->totpoint = 4; break;
		case CURVE_PRESET_SMOOTH: cuma->totpoint = 4; break;
		case CURVE_PRESET_MAX: cuma->totpoint = 2; break;
		case CURVE_PRESET_MID9: cuma->totpoint = 9; break;
		case CURVE_PRESET_ROUND: cuma->totpoint = 4; break;
		case CURVE_PRESET_ROOT: cuma->totpoint = 4; break;
	}

	cuma->curve = MEM_callocN(cuma->totpoint * sizeof(CurveMapPoint), "curve points");

	switch (preset) {
		case CURVE_PRESET_LINE:
			cuma->curve[0].x = clipr->xmin;
			cuma->curve[0].y = clipr->ymax;
			cuma->curve[1].x = clipr->xmax;
			cuma->curve[1].y = clipr->ymin;
			if (slope == CURVEMAP_SLOPE_POS_NEG) {
				cuma->curve[0].flag |= CUMA_HANDLE_VECTOR;
				cuma->curve[1].flag |= CUMA_HANDLE_VECTOR;
			}
			break;
		case CURVE_PRESET_SHARP:
			cuma->curve[0].x = 0;
			cuma->curve[0].y = 1;
			cuma->curve[1].x = 0.25;
			cuma->curve[1].y = 0.50;
			cuma->curve[2].x = 0.75;
			cuma->curve[2].y = 0.04;
			cuma->curve[3].x = 1;
			cuma->curve[3].y = 0;
			break;
		case CURVE_PRESET_SMOOTH:
			cuma->curve[0].x = 0;
			cuma->curve[0].y = 1;
			cuma->curve[1].x = 0.25;
			cuma->curve[1].y = 0.94;
			cuma->curve[2].x = 0.75;
			cuma->curve[2].y = 0.06;
			cuma->curve[3].x = 1;
			cuma->curve[3].y = 0;
			break;
		case CURVE_PRESET_MAX:
			cuma->curve[0].x = 0;
			cuma->curve[0].y = 1;
			cuma->curve[1].x = 1;
			cuma->curve[1].y = 1;
			break;
		case CURVE_PRESET_MID9:
		{
			int i;
			for (i = 0; i < cuma->totpoint; i++) {
				cuma->curve[i].x = i / ((float)cuma->totpoint - 1);
				cuma->curve[i].y = 0.5;
			}
			break;
		}
		case CURVE_PRESET_ROUND:
			cuma->curve[0].x = 0;
			cuma->curve[0].y = 1;
			cuma->curve[1].x = 0.5;
			cuma->curve[1].y = 0.90;
			cuma->curve[2].x = 0.86;
			cuma->curve[2].y = 0.5;
			cuma->curve[3].x = 1;
			cuma->curve[3].y = 0;
			break;
		case CURVE_PRESET_ROOT:
			cuma->curve[0].x = 0;
			cuma->curve[0].y = 1;
			cuma->curve[1].x = 0.25;
			cuma->curve[1].y = 0.95;
			cuma->curve[2].x = 0.75;
			cuma->curve[2].y = 0.44;
			cuma->curve[3].x = 1;
			cuma->curve[3].y = 0;
			break;
	}

	/* mirror curve in x direction to have positive slope
	 * rather than default negative slope */
	if (slope == CURVEMAP_SLOPE_POSITIVE) {
		int i, last = cuma->totpoint - 1;
		CurveMapPoint *newpoints = MEM_dupallocN(cuma->curve);
		
		for (i = 0; i < cuma->totpoint; i++) {
			newpoints[i].y = cuma->curve[last - i].y;
		}
		
		MEM_freeN(cuma->curve);
		cuma->curve = newpoints;
	}
	else if (slope == CURVEMAP_SLOPE_POS_NEG) {
		const int num_points = cuma->totpoint * 2 - 1;
		CurveMapPoint *new_points = MEM_mallocN(num_points * sizeof(CurveMapPoint),
		                                       "curve symmetric points");
		int i;
		for (i = 0; i < cuma->totpoint; i++) {
			const int src_last_point = cuma->totpoint - i - 1;
			const int dst_last_point = num_points - i - 1;
			new_points[i] = cuma->curve[src_last_point];
			new_points[i].x = (1.0f - cuma->curve[src_last_point].x) * 0.5f;
			new_points[dst_last_point] = new_points[i];
			new_points[dst_last_point].x = 0.5f + cuma->curve[src_last_point].x * 0.5f;
		}
		cuma->totpoint = num_points;
		MEM_freeN(cuma->curve);
		cuma->curve = new_points;
	}

	if (cuma->table) {
		MEM_freeN(cuma->table);
		cuma->table = NULL;
	}
}

/**
 * \param type: eBezTriple_Handle
 */
void curvemap_handle_set(CurveMap *cuma, int type)
{
	int a;
	
	for (a = 0; a < cuma->totpoint; a++) {
		if (cuma->curve[a].flag & CUMA_SELECT) {
			cuma->curve[a].flag &= ~(CUMA_HANDLE_VECTOR | CUMA_HANDLE_AUTO_ANIM);
			if (type == HD_VECT) {
				cuma->curve[a].flag |= CUMA_HANDLE_VECTOR;
			}
			else if (type == HD_AUTO_ANIM) {
				cuma->curve[a].flag |= CUMA_HANDLE_AUTO_ANIM;
			}
			else {
				/* pass */
			}
		}
	}
}

/* *********************** Making the tables and display ************** */

/**
 * reduced copy of #calchandleNurb_intern code in curve.c
 */
static void calchandle_curvemap(
        BezTriple *bezt, const BezTriple *prev, const BezTriple *next)
{
	/* defines to avoid confusion */
#define p2_h1 ((p2) - 3)
#define p2_h2 ((p2) + 3)

	const float *p1, *p3;
	float *p2;
	float pt[3];
	float len, len_a, len_b;
	float dvec_a[2], dvec_b[2];

	if (bezt->h1 == 0 && bezt->h2 == 0) {
		return;
	}
	
	p2 = bezt->vec[1];
	
	if (prev == NULL) {
		p3 = next->vec[1];
		pt[0] = 2.0f * p2[0] - p3[0];
		pt[1] = 2.0f * p2[1] - p3[1];
		p1 = pt;
	}
	else {
		p1 = prev->vec[1];
	}
	
	if (next == NULL) {
		p1 = prev->vec[1];
		pt[0] = 2.0f * p2[0] - p1[0];
		pt[1] = 2.0f * p2[1] - p1[1];
		p3 = pt;
	}
	else {
		p3 = next->vec[1];
	}

	sub_v2_v2v2(dvec_a, p2, p1);
	sub_v2_v2v2(dvec_b, p3, p2);

	len_a = len_v2(dvec_a);
	len_b = len_v2(dvec_b);

	if (len_a == 0.0f) len_a = 1.0f;
	if (len_b == 0.0f) len_b = 1.0f;

	if (ELEM(bezt->h1, HD_AUTO, HD_AUTO_ANIM) || ELEM(bezt->h2, HD_AUTO, HD_AUTO_ANIM)) {    /* auto */
		float tvec[2];
		tvec[0] = dvec_b[0] / len_b + dvec_a[0] / len_a;
		tvec[1] = dvec_b[1] / len_b + dvec_a[1] / len_a;

		len = len_v2(tvec) * 2.5614f;
		if (len != 0.0f) {
			
			if (ELEM(bezt->h1, HD_AUTO, HD_AUTO_ANIM)) {
				len_a /= len;
				madd_v2_v2v2fl(p2_h1, p2, tvec, -len_a);

				if ((bezt->h1 == HD_AUTO_ANIM) && next && prev) { /* keep horizontal if extrema */
					const float ydiff1 = prev->vec[1][1] - bezt->vec[1][1];
					const float ydiff2 = next->vec[1][1] - bezt->vec[1][1];
					if ((ydiff1 <= 0.0f && ydiff2 <= 0.0f) ||
					    (ydiff1 >= 0.0f && ydiff2 >= 0.0f))
					{
						bezt->vec[0][1] = bezt->vec[1][1];
					}
					else { /* handles should not be beyond y coord of two others */
						if (ydiff1 <= 0.0f) {
							if (prev->vec[1][1] > bezt->vec[0][1]) {
								bezt->vec[0][1] = prev->vec[1][1];
							}
						}
						else {
							if (prev->vec[1][1] < bezt->vec[0][1]) {
								bezt->vec[0][1] = prev->vec[1][1];
							}
						}
					}
				}
			}
			if (ELEM(bezt->h2, HD_AUTO, HD_AUTO_ANIM)) {
				len_b /= len;
				madd_v2_v2v2fl(p2_h2, p2, tvec,  len_b);

				if ((bezt->h2 == HD_AUTO_ANIM) && next && prev) { /* keep horizontal if extrema */
					const float ydiff1 = prev->vec[1][1] - bezt->vec[1][1];
					const float ydiff2 = next->vec[1][1] - bezt->vec[1][1];
					if ((ydiff1 <= 0.0f && ydiff2 <= 0.0f) ||
					    (ydiff1 >= 0.0f && ydiff2 >= 0.0f))
					{
						bezt->vec[2][1] = bezt->vec[1][1];
					}
					else { /* handles should not be beyond y coord of two others */
						if (ydiff1 <= 0.0f) {
							if (next->vec[1][1] < bezt->vec[2][1]) {
								bezt->vec[2][1] = next->vec[1][1];
							}
						}
						else {
							if (next->vec[1][1] > bezt->vec[2][1]) {
								bezt->vec[2][1] = next->vec[1][1];
							}
						}
					}
				}
			}
		}
	}

	if (bezt->h1 == HD_VECT) {    /* vector */
		madd_v2_v2v2fl(p2_h1, p2, dvec_a, -1.0f / 3.0f);
	}
	if (bezt->h2 == HD_VECT) {
		madd_v2_v2v2fl(p2_h2, p2, dvec_b,  1.0f / 3.0f);
	}

#undef p2_h1
#undef p2_h2
}

/* in X, out Y. 
 * X is presumed to be outside first or last */
static float curvemap_calc_extend(const CurveMap *cuma, float x, const float first[2], const float last[2])
{
	if (x <= first[0]) {
		if ((cuma->flag & CUMA_EXTEND_EXTRAPOLATE) == 0) {
			/* no extrapolate */
			return first[1];
		}
		else {
			if (cuma->ext_in[0] == 0.0f)
				return first[1] + cuma->ext_in[1] * 10000.0f;
			else
				return first[1] + cuma->ext_in[1] * (x - first[0]) / cuma->ext_in[0];
		}
	}
	else if (x >= last[0]) {
		if ((cuma->flag & CUMA_EXTEND_EXTRAPOLATE) == 0) {
			/* no extrapolate */
			return last[1];
		}
		else {
			if (cuma->ext_out[0] == 0.0f)
				return last[1] - cuma->ext_out[1] * 10000.0f;
			else
				return last[1] + cuma->ext_out[1] * (x - last[0]) / cuma->ext_out[0];
		}
	}
	return 0.0f;
}

/* only creates a table for a single channel in CurveMapping */
static void curvemap_make_table(CurveMap *cuma, const rctf *clipr)
{
	CurveMapPoint *cmp = cuma->curve;
	BezTriple *bezt;
	float *fp, *allpoints, *lastpoint, curf, range;
	int a, totpoint;
	
	if (cuma->curve == NULL) return;
	
	/* default rect also is table range */
	cuma->mintable = clipr->xmin;
	cuma->maxtable = clipr->xmax;
	
	/* hrmf... we now rely on blender ipo beziers, these are more advanced */
	bezt = MEM_callocN(cuma->totpoint * sizeof(BezTriple), "beztarr");
	
	for (a = 0; a < cuma->totpoint; a++) {
		cuma->mintable = min_ff(cuma->mintable, cmp[a].x);
		cuma->maxtable = max_ff(cuma->maxtable, cmp[a].x);
		bezt[a].vec[1][0] = cmp[a].x;
		bezt[a].vec[1][1] = cmp[a].y;
		if (cmp[a].flag & CUMA_HANDLE_VECTOR) {
			bezt[a].h1 = bezt[a].h2 = HD_VECT;
		}
		else if (cmp[a].flag & CUMA_HANDLE_AUTO_ANIM) {
			bezt[a].h1 = bezt[a].h2 = HD_AUTO_ANIM;
		}
		else {
			bezt[a].h1 = bezt[a].h2 = HD_AUTO;
		}
	}
	
	const BezTriple *bezt_prev = NULL;
	for (a = 0; a < cuma->totpoint; a++) {
		const BezTriple *bezt_next = (a != cuma->totpoint - 1) ? &bezt[a + 1] : NULL;
		calchandle_curvemap(&bezt[a], bezt_prev, bezt_next);
		bezt_prev = &bezt[a];
	}
	
	/* first and last handle need correction, instead of pointing to center of next/prev, 
	 * we let it point to the closest handle */
	if (cuma->totpoint > 2) {
		float hlen, nlen, vec[3];
		
		if (bezt[0].h2 == HD_AUTO) {
			
			hlen = len_v3v3(bezt[0].vec[1], bezt[0].vec[2]); /* original handle length */
			/* clip handle point */
			copy_v3_v3(vec, bezt[1].vec[0]);
			if (vec[0] < bezt[0].vec[1][0])
				vec[0] = bezt[0].vec[1][0];
			
			sub_v3_v3(vec, bezt[0].vec[1]);
			nlen = len_v3(vec);
			if (nlen > FLT_EPSILON) {
				mul_v3_fl(vec, hlen / nlen);
				add_v3_v3v3(bezt[0].vec[2], vec, bezt[0].vec[1]);
				sub_v3_v3v3(bezt[0].vec[0], bezt[0].vec[1], vec);
			}
		}
		a = cuma->totpoint - 1;
		if (bezt[a].h2 == HD_AUTO) {
			
			hlen = len_v3v3(bezt[a].vec[1], bezt[a].vec[0]); /* original handle length */
			/* clip handle point */
			copy_v3_v3(vec, bezt[a - 1].vec[2]);
			if (vec[0] > bezt[a].vec[1][0])
				vec[0] = bezt[a].vec[1][0];
			
			sub_v3_v3(vec, bezt[a].vec[1]);
			nlen = len_v3(vec);
			if (nlen > FLT_EPSILON) {
				mul_v3_fl(vec, hlen / nlen);
				add_v3_v3v3(bezt[a].vec[0], vec, bezt[a].vec[1]);
				sub_v3_v3v3(bezt[a].vec[2], bezt[a].vec[1], vec);
			}
		}
	}
	/* make the bezier curve */
	if (cuma->table)
		MEM_freeN(cuma->table);
	totpoint = (cuma->totpoint - 1) * CM_RESOL;
	fp = allpoints = MEM_callocN(totpoint * 2 * sizeof(float), "table");
	
	for (a = 0; a < cuma->totpoint - 1; a++, fp += 2 * CM_RESOL) {
		correct_bezpart(bezt[a].vec[1], bezt[a].vec[2], bezt[a + 1].vec[0], bezt[a + 1].vec[1]);
		BKE_curve_forward_diff_bezier(bezt[a].vec[1][0], bezt[a].vec[2][0], bezt[a + 1].vec[0][0], bezt[a + 1].vec[1][0], fp, CM_RESOL - 1, 2 * sizeof(float));
		BKE_curve_forward_diff_bezier(bezt[a].vec[1][1], bezt[a].vec[2][1], bezt[a + 1].vec[0][1], bezt[a + 1].vec[1][1], fp + 1, CM_RESOL - 1, 2 * sizeof(float));
	}
	
	/* store first and last handle for extrapolation, unit length */
	cuma->ext_in[0] = bezt[0].vec[0][0] - bezt[0].vec[1][0];
	cuma->ext_in[1] = bezt[0].vec[0][1] - bezt[0].vec[1][1];
	range = sqrtf(cuma->ext_in[0] * cuma->ext_in[0] + cuma->ext_in[1] * cuma->ext_in[1]);
	cuma->ext_in[0] /= range;
	cuma->ext_in[1] /= range;

	a = cuma->totpoint - 1;
	cuma->ext_out[0] = bezt[a].vec[1][0] - bezt[a].vec[2][0];
	cuma->ext_out[1] = bezt[a].vec[1][1] - bezt[a].vec[2][1];
	range = sqrtf(cuma->ext_out[0] * cuma->ext_out[0] + cuma->ext_out[1] * cuma->ext_out[1]);
	cuma->ext_out[0] /= range;
	cuma->ext_out[1] /= range;
	
	/* cleanup */
	MEM_freeN(bezt);

	range = CM_TABLEDIV * (cuma->maxtable - cuma->mintable);
	cuma->range = 1.0f / range;
	
	/* now make a table with CM_TABLE equal x distances */
	fp = allpoints;
	lastpoint = allpoints + 2 * (totpoint - 1);
	cmp = MEM_callocN((CM_TABLE + 1) * sizeof(CurveMapPoint), "dist table");

	for (a = 0; a <= CM_TABLE; a++) {
		curf = cuma->mintable + range * (float)a;
		cmp[a].x = curf;
		
		/* get the first x coordinate larger than curf */
		while (curf >= fp[0] && fp != lastpoint) {
			fp += 2;
		}
		if (fp == allpoints || (curf >= fp[0] && fp == lastpoint))
			cmp[a].y = curvemap_calc_extend(cuma, curf, allpoints, lastpoint);
		else {
			float fac1 = fp[0] - fp[-2];
			float fac2 = fp[0] - curf;
			if (fac1 > FLT_EPSILON)
				fac1 = fac2 / fac1;
			else
				fac1 = 0.0f;
			cmp[a].y = fac1 * fp[-1] + (1.0f - fac1) * fp[1];
		}
	}
	
	MEM_freeN(allpoints);
	cuma->table = cmp;
}

/* call when you do images etc, needs restore too. also verifies tables */
/* it uses a flag to prevent premul or free to happen twice */
void curvemapping_premultiply(CurveMapping *cumap, int restore)
{
	int a;
	
	if (restore) {
		if (cumap->flag & CUMA_PREMULLED) {
			for (a = 0; a < 3; a++) {
				MEM_freeN(cumap->cm[a].table);
				cumap->cm[a].table = cumap->cm[a].premultable;
				cumap->cm[a].premultable = NULL;

				copy_v2_v2(cumap->cm[a].ext_in, cumap->cm[a].premul_ext_in);
				copy_v2_v2(cumap->cm[a].ext_out, cumap->cm[a].premul_ext_out);
				zero_v2(cumap->cm[a].premul_ext_in);
				zero_v2(cumap->cm[a].premul_ext_out);
			}
			
			cumap->flag &= ~CUMA_PREMULLED;
		}
	}
	else {
		if ((cumap->flag & CUMA_PREMULLED) == 0) {
			/* verify and copy */
			for (a = 0; a < 3; a++) {
				if (cumap->cm[a].table == NULL)
					curvemap_make_table(cumap->cm + a, &cumap->clipr);
				cumap->cm[a].premultable = cumap->cm[a].table;
				cumap->cm[a].table = MEM_mallocN((CM_TABLE + 1) * sizeof(CurveMapPoint), "premul table");
				memcpy(cumap->cm[a].table, cumap->cm[a].premultable, (CM_TABLE + 1) * sizeof(CurveMapPoint));
			}
			
			if (cumap->cm[3].table == NULL)
				curvemap_make_table(cumap->cm + 3, &cumap->clipr);
		
			/* premul */
			for (a = 0; a < 3; a++) {
				int b;
				for (b = 0; b <= CM_TABLE; b++) {
					cumap->cm[a].table[b].y = curvemap_evaluateF(cumap->cm + 3, cumap->cm[a].table[b].y);
				}

				copy_v2_v2(cumap->cm[a].premul_ext_in, cumap->cm[a].ext_in);
				copy_v2_v2(cumap->cm[a].premul_ext_out, cumap->cm[a].ext_out);
				mul_v2_v2(cumap->cm[a].ext_in, cumap->cm[3].ext_in);
				mul_v2_v2(cumap->cm[a].ext_out, cumap->cm[3].ext_out);
			}
			
			cumap->flag |= CUMA_PREMULLED;
		}
	}
}

static int sort_curvepoints(const void *a1, const void *a2)
{
	const struct CurveMapPoint *x1 = a1, *x2 = a2;
	
	if (x1->x > x2->x) return 1;
	else if (x1->x < x2->x) return -1;
	return 0;
}

/* ************************ more CurveMapping calls *************** */

/* note; only does current curvemap! */
void curvemapping_changed(CurveMapping *cumap, const bool rem_doubles)
{
	CurveMap *cuma = cumap->cm + cumap->cur;
	CurveMapPoint *cmp = cuma->curve;
	rctf *clipr = &cumap->clipr;
	float thresh = 0.01f * BLI_rctf_size_x(clipr);
	float dx = 0.0f, dy = 0.0f;
	int a;

	cumap->changed_timestamp++;

	/* clamp with clip */
	if (cumap->flag & CUMA_DO_CLIP) {
		for (a = 0; a < cuma->totpoint; a++) {
			if (cmp[a].flag & CUMA_SELECT) {
				if (cmp[a].x < clipr->xmin)
					dx = min_ff(dx, cmp[a].x - clipr->xmin);
				else if (cmp[a].x > clipr->xmax)
					dx = max_ff(dx, cmp[a].x - clipr->xmax);
				if (cmp[a].y < clipr->ymin)
					dy = min_ff(dy, cmp[a].y - clipr->ymin);
				else if (cmp[a].y > clipr->ymax)
					dy = max_ff(dy, cmp[a].y - clipr->ymax);
			}
		}
		for (a = 0; a < cuma->totpoint; a++) {
			if (cmp[a].flag & CUMA_SELECT) {
				cmp[a].x -= dx;
				cmp[a].y -= dy;
			}
		}

		/* ensure zoom-level respects clipping */
		if (BLI_rctf_size_x(&cumap->curr) > BLI_rctf_size_x(&cumap->clipr)) {
			cumap->curr.xmin = cumap->clipr.xmin;
			cumap->curr.xmax = cumap->clipr.xmax;
		}
		if (BLI_rctf_size_y(&cumap->curr) > BLI_rctf_size_y(&cumap->clipr)) {
			cumap->curr.ymin = cumap->clipr.ymin;
			cumap->curr.ymax = cumap->clipr.ymax;
		}
	}
	
	
	qsort(cmp, cuma->totpoint, sizeof(CurveMapPoint), sort_curvepoints);
	
	/* remove doubles, threshold set on 1% of default range */
	if (rem_doubles && cuma->totpoint > 2) {
		for (a = 0; a < cuma->totpoint - 1; a++) {
			dx = cmp[a].x - cmp[a + 1].x;
			dy = cmp[a].y - cmp[a + 1].y;
			if (sqrtf(dx * dx + dy * dy) < thresh) {
				if (a == 0) {
					cmp[a + 1].flag |= CUMA_HANDLE_VECTOR;
					if (cmp[a + 1].flag & CUMA_SELECT)
						cmp[a].flag |= CUMA_SELECT;
				}
				else {
					cmp[a].flag |= CUMA_HANDLE_VECTOR;
					if (cmp[a].flag & CUMA_SELECT)
						cmp[a + 1].flag |= CUMA_SELECT;
				}
				break;  /* we assume 1 deletion per edit is ok */
			}
		}
		if (a != cuma->totpoint - 1)
			curvemap_remove(cuma, 2);
	}
	curvemap_make_table(cuma, clipr);
}

void curvemapping_changed_all(CurveMapping *cumap)
{
	int a, cur = cumap->cur;

	for (a = 0; a < CM_TOT; a++) {
		if (cumap->cm[a].curve) {
			cumap->cur = a;
			curvemapping_changed(cumap, false);
		}
	}

	cumap->cur = cur;
}

/* table should be verified */
float curvemap_evaluateF(const CurveMap *cuma, float value)
{
	float fi;
	int i;

	/* index in table */
	fi = (value - cuma->mintable) * cuma->range;
	i = (int)fi;
	
	/* fi is table float index and should check against table range i.e. [0.0 CM_TABLE] */
	if (fi < 0.0f || fi > CM_TABLE)
		return curvemap_calc_extend(cuma, value, &cuma->table[0].x, &cuma->table[CM_TABLE].x);
	else {
		if (i < 0) return cuma->table[0].y;
		if (i >= CM_TABLE) return cuma->table[CM_TABLE].y;
		
		fi = fi - (float)i;
		return (1.0f - fi) * cuma->table[i].y + (fi) * cuma->table[i + 1].y;
	}
}

/* works with curve 'cur' */
float curvemapping_evaluateF(const CurveMapping *cumap, int cur, float value)
{
	const CurveMap *cuma = cumap->cm + cur;
	float val = curvemap_evaluateF(cuma, value);

	/* account for clipping */
	if (cumap->flag & CUMA_DO_CLIP) {
		if (val < cumap->curr.ymin)
			val = cumap->curr.ymin;
		else if (val > cumap->curr.ymax)
			val = cumap->curr.ymax;
	}

	return val;
}

/* vector case */
void curvemapping_evaluate3F(const CurveMapping *cumap, float vecout[3], const float vecin[3])
{
	vecout[0] = curvemap_evaluateF(&cumap->cm[0], vecin[0]);
	vecout[1] = curvemap_evaluateF(&cumap->cm[1], vecin[1]);
	vecout[2] = curvemap_evaluateF(&cumap->cm[2], vecin[2]);
}

/* RGB case, no black/white points, no premult */
void curvemapping_evaluateRGBF(const CurveMapping *cumap, float vecout[3], const float vecin[3])
{
	vecout[0] = curvemap_evaluateF(&cumap->cm[0], curvemap_evaluateF(&cumap->cm[3], vecin[0]));
	vecout[1] = curvemap_evaluateF(&cumap->cm[1], curvemap_evaluateF(&cumap->cm[3], vecin[1]));
	vecout[2] = curvemap_evaluateF(&cumap->cm[2], curvemap_evaluateF(&cumap->cm[3], vecin[2]));
}

/** same as #curvemapping_evaluate_premulRGBF
 * but black/bwmul are passed as args for the compositor
 * where they can change per pixel.
 *
 * Use in conjunction with #curvemapping_set_black_white_ex
 *
 * \param black Use instead of cumap->black
 * \param bwmul Use instead of cumap->bwmul
 */
void curvemapping_evaluate_premulRGBF_ex(const CurveMapping *cumap, float vecout[3], const float vecin[3],
                                         const float black[3], const float bwmul[3])
{
	vecout[0] = curvemap_evaluateF(&cumap->cm[0], (vecin[0] - black[0]) * bwmul[0]);
	vecout[1] = curvemap_evaluateF(&cumap->cm[1], (vecin[1] - black[1]) * bwmul[1]);
	vecout[2] = curvemap_evaluateF(&cumap->cm[2], (vecin[2] - black[2]) * bwmul[2]);
}

/* RGB with black/white points and premult. tables are checked */
void curvemapping_evaluate_premulRGBF(const CurveMapping *cumap, float vecout[3], const float vecin[3])
{
	vecout[0] = curvemap_evaluateF(&cumap->cm[0], (vecin[0] - cumap->black[0]) * cumap->bwmul[0]);
	vecout[1] = curvemap_evaluateF(&cumap->cm[1], (vecin[1] - cumap->black[1]) * cumap->bwmul[1]);
	vecout[2] = curvemap_evaluateF(&cumap->cm[2], (vecin[2] - cumap->black[2]) * cumap->bwmul[2]);
}

/* same as above, byte version */
void curvemapping_evaluate_premulRGB(const CurveMapping *cumap, unsigned char vecout_byte[3], const unsigned char vecin_byte[3])
{
	float vecin[3], vecout[3];

	vecin[0] = (float) vecin_byte[0] / 255.0f;
	vecin[1] = (float) vecin_byte[1] / 255.0f;
	vecin[2] = (float) vecin_byte[2] / 255.0f;

	curvemapping_evaluate_premulRGBF(cumap, vecout, vecin);

	vecout_byte[0] = FTOCHAR(vecout[0]);
	vecout_byte[1] = FTOCHAR(vecout[1]);
	vecout_byte[2] = FTOCHAR(vecout[2]);
}

int curvemapping_RGBA_does_something(const CurveMapping *cumap)
{
	int a;
	
	if (cumap->black[0] != 0.0f) return 1;
	if (cumap->black[1] != 0.0f) return 1;
	if (cumap->black[2] != 0.0f) return 1;
	if (cumap->white[0] != 1.0f) return 1;
	if (cumap->white[1] != 1.0f) return 1;
	if (cumap->white[2] != 1.0f) return 1;
	
	for (a = 0; a < CM_TOT; a++) {
		if (cumap->cm[a].curve) {
			if (cumap->cm[a].totpoint != 2) return 1;
			
			if (cumap->cm[a].curve[0].x != 0.0f) return 1;
			if (cumap->cm[a].curve[0].y != 0.0f) return 1;
			if (cumap->cm[a].curve[1].x != 1.0f) return 1;
			if (cumap->cm[a].curve[1].y != 1.0f) return 1;
		}
	}
	return 0;
}

void curvemapping_initialize(CurveMapping *cumap)
{
	int a;
	
	if (cumap == NULL) return;
	
	for (a = 0; a < CM_TOT; a++) {
		if (cumap->cm[a].table == NULL)
			curvemap_make_table(cumap->cm + a, &cumap->clipr);
	}
}

void curvemapping_table_RGBA(const CurveMapping *cumap, float **array, int *size)
{
	int a;
	
	*size = CM_TABLE + 1;
	*array = MEM_callocN(sizeof(float) * (*size) * 4, "CurveMapping");

	for (a = 0; a < *size; a++) {
		if (cumap->cm[0].table)
			(*array)[a * 4 + 0] = cumap->cm[0].table[a].y;
		if (cumap->cm[1].table)
			(*array)[a * 4 + 1] = cumap->cm[1].table[a].y;
		if (cumap->cm[2].table)
			(*array)[a * 4 + 2] = cumap->cm[2].table[a].y;
		if (cumap->cm[3].table)
			(*array)[a * 4 + 3] = cumap->cm[3].table[a].y;
	}
}

/* ***************** Histogram **************** */

#define INV_255     (1.f / 255.f)

BLI_INLINE int get_bin_float(float f)
{
	int bin = (int)((f * 255.0f) + 0.5f);  /* 0.5 to prevent quantisation differences */

	/* note: clamp integer instead of float to avoid problems with NaN */
	CLAMP(bin, 0, 255);

	return bin;
}

static void save_sample_line(Scopes *scopes, const int idx, const float fx, const float rgb[3], const float ycc[3])
{
	float yuv[3];

	/* vectorscope*/
	rgb_to_yuv(rgb[0], rgb[1], rgb[2], &yuv[0], &yuv[1], &yuv[2], BLI_YUV_ITU_BT709);
	scopes->vecscope[idx + 0] = yuv[1];
	scopes->vecscope[idx + 1] = yuv[2];

	/* waveform */
	switch (scopes->wavefrm_mode) {
		case SCOPES_WAVEFRM_RGB:
		case SCOPES_WAVEFRM_RGB_PARADE:
			scopes->waveform_1[idx + 0] = fx;
			scopes->waveform_1[idx + 1] = rgb[0];
			scopes->waveform_2[idx + 0] = fx;
			scopes->waveform_2[idx + 1] = rgb[1];
			scopes->waveform_3[idx + 0] = fx;
			scopes->waveform_3[idx + 1] = rgb[2];
			break;
		case SCOPES_WAVEFRM_LUMA:
			scopes->waveform_1[idx + 0] = fx;
			scopes->waveform_1[idx + 1] = ycc[0];
			break;
		case SCOPES_WAVEFRM_YCC_JPEG:
		case SCOPES_WAVEFRM_YCC_709:
		case SCOPES_WAVEFRM_YCC_601:
			scopes->waveform_1[idx + 0] = fx;
			scopes->waveform_1[idx + 1] = ycc[0];
			scopes->waveform_2[idx + 0] = fx;
			scopes->waveform_2[idx + 1] = ycc[1];
			scopes->waveform_3[idx + 0] = fx;
			scopes->waveform_3[idx + 1] = ycc[2];
			break;
	}
}

void BKE_histogram_update_sample_line(Histogram *hist, ImBuf *ibuf, const ColorManagedViewSettings *view_settings,
                                      const ColorManagedDisplaySettings *display_settings)
{
	int i, x, y;
	const float *fp;
	unsigned char *cp;

	int x1 = 0.5f + hist->co[0][0] * ibuf->x;
	int x2 = 0.5f + hist->co[1][0] * ibuf->x;
	int y1 = 0.5f + hist->co[0][1] * ibuf->y;
	int y2 = 0.5f + hist->co[1][1] * ibuf->y;

	struct ColormanageProcessor *cm_processor = NULL;

	hist->channels = 3;
	hist->x_resolution = 256;
	hist->xmax = 1.0f;
	/* hist->ymax = 1.0f; */ /* now do this on the operator _only_ */

	if (ibuf->rect == NULL && ibuf->rect_float == NULL) return;

	if (ibuf->rect_float)
		cm_processor = IMB_colormanagement_display_processor_new(view_settings, display_settings);

	for (i = 0; i < 256; i++) {
		x = (int)(0.5f + x1 + (float)i * (x2 - x1) / 255.0f);
		y = (int)(0.5f + y1 + (float)i * (y2 - y1) / 255.0f);

		if (x < 0 || y < 0 || x >= ibuf->x || y >= ibuf->y) {
			hist->data_luma[i] = hist->data_r[i] = hist->data_g[i] = hist->data_b[i] = hist->data_a[i] = 0.0f;
		}
		else {
			if (ibuf->rect_float) {
				float rgba[4];
				fp = (ibuf->rect_float + (ibuf->channels) * (y * ibuf->x + x));

				switch (ibuf->channels) {
					case 4:
						copy_v4_v4(rgba, fp);
						IMB_colormanagement_processor_apply_v4(cm_processor, rgba);
						break;
					case 3:
						copy_v3_v3(rgba, fp);
						IMB_colormanagement_processor_apply_v3(cm_processor, rgba);
						rgba[3] = 1.0f;
						break;
					case 2:
						copy_v3_fl(rgba, fp[0]);
						rgba[3] = fp[1];
						break;
					case 1:
						copy_v3_fl(rgba, fp[0]);
						rgba[3] = 1.0f;
						break;
					default:
						BLI_assert(0);
				}

				hist->data_luma[i]  = IMB_colormanagement_get_luminance(rgba);
				hist->data_r[i]     = rgba[0];
				hist->data_g[i]     = rgba[1];
				hist->data_b[i]     = rgba[2];
				hist->data_a[i]     = rgba[3];
			}
			else if (ibuf->rect) {
				cp = (unsigned char *)(ibuf->rect + y * ibuf->x + x);
				hist->data_luma[i]  = (float)IMB_colormanagement_get_luminance_byte(cp) / 255.0f;
				hist->data_r[i]     = (float)cp[0] / 255.0f;
				hist->data_g[i]     = (float)cp[1] / 255.0f;
				hist->data_b[i]     = (float)cp[2] / 255.0f;
				hist->data_a[i]     = (float)cp[3] / 255.0f;
			}
		}
	}

	if (cm_processor)
		IMB_colormanagement_processor_free(cm_processor);
}

/* if view_settings, it also applies this to byte buffers */
typedef struct ScopesUpdateData {
	Scopes *scopes;
	const ImBuf *ibuf;
	struct ColormanageProcessor *cm_processor;
	const unsigned char *display_buffer;
	const int ycc_mode;

	unsigned int *bin_lum, *bin_r, *bin_g, *bin_b, *bin_a;
} ScopesUpdateData;

typedef struct ScopesUpdateDataChunk {
	unsigned int bin_lum[256];
	unsigned int bin_r[256];
	unsigned int bin_g[256];
	unsigned int bin_b[256];
	unsigned int bin_a[256];
	float min[3], max[3];
} ScopesUpdateDataChunk;

static void scopes_update_cb(void *__restrict userdata, 
                             const int y,
                             const ParallelRangeTLS *__restrict tls)
{
	const ScopesUpdateData *data = userdata;

	Scopes *scopes = data->scopes;
	const ImBuf *ibuf = data->ibuf;
	struct ColormanageProcessor *cm_processor = data->cm_processor;
	const unsigned char *display_buffer = data->display_buffer;
	const int ycc_mode = data->ycc_mode;

	ScopesUpdateDataChunk *data_chunk = tls->userdata_chunk;
	unsigned int *bin_lum = data_chunk->bin_lum;
	unsigned int *bin_r = data_chunk->bin_r;
	unsigned int *bin_g = data_chunk->bin_g;
	unsigned int *bin_b = data_chunk->bin_b;
	unsigned int *bin_a = data_chunk->bin_a;
	float *min = data_chunk->min;
	float *max = data_chunk->max;

	const float *rf = NULL;
	const unsigned char *rc = NULL;
	const int rows_per_sample_line = ibuf->y / scopes->sample_lines;
	const int savedlines = y / rows_per_sample_line;
	const bool do_sample_line = (savedlines < scopes->sample_lines) && (y % rows_per_sample_line) == 0;
	const bool is_float = (ibuf->rect_float != NULL);

	if (is_float)
		rf = ibuf->rect_float + ((size_t)y) * ibuf->x * ibuf->channels;
	else {
		rc = display_buffer + ((size_t)y) * ibuf->x * ibuf->channels;
	}

	for (int x = 0; x < ibuf->x; x++) {
		float rgba[4], ycc[3], luma;

		if (is_float) {
			switch (ibuf->channels) {
				case 4:
					copy_v4_v4(rgba, rf);
					IMB_colormanagement_processor_apply_v4(cm_processor, rgba);
					break;
				case 3:
					copy_v3_v3(rgba, rf);
					IMB_colormanagement_processor_apply_v3(cm_processor, rgba);
					rgba[3] = 1.0f;
					break;
				case 2:
					copy_v3_fl(rgba, rf[0]);
					rgba[3] = rf[1];
					break;
				case 1:
					copy_v3_fl(rgba, rf[0]);
					rgba[3] = 1.0f;
					break;
				default:
					BLI_assert(0);
			}
		}
		else {
			for (int c = 4; c--;)
				rgba[c] = rc[c] * INV_255;
		}

		/* we still need luma for histogram */
		luma = IMB_colormanagement_get_luminance(rgba);

		/* check for min max */
		if (ycc_mode == -1) {
			minmax_v3v3_v3(min, max, rgba);
		}
		else {
			rgb_to_ycc(rgba[0], rgba[1], rgba[2], &ycc[0], &ycc[1], &ycc[2], ycc_mode);
			mul_v3_fl(ycc, INV_255);
			minmax_v3v3_v3(min, max, ycc);
		}
		/* increment count for histo*/
		bin_lum[get_bin_float(luma)]++;
		bin_r[get_bin_float(rgba[0])]++;
		bin_g[get_bin_float(rgba[1])]++;
		bin_b[get_bin_float(rgba[2])]++;
		bin_a[get_bin_float(rgba[3])]++;

		/* save sample if needed */
		if (do_sample_line) {
			const float fx = (float)x / (float)ibuf->x;
			const int idx = 2 * (ibuf->x * savedlines + x);
			save_sample_line(scopes, idx, fx, rgba, ycc);
		}

		rf += ibuf->channels;
		rc += ibuf->channels;
	}
}

static void scopes_update_finalize(void *__restrict userdata,
                                   void *__restrict userdata_chunk)
{
	const ScopesUpdateData *data = userdata;
	const ScopesUpdateDataChunk *data_chunk = userdata_chunk;

	unsigned int *bin_lum = data->bin_lum;
	unsigned int *bin_r = data->bin_r;
	unsigned int *bin_g = data->bin_g;
	unsigned int *bin_b = data->bin_b;
	unsigned int *bin_a = data->bin_a;
	const unsigned int *bin_lum_c = data_chunk->bin_lum;
	const unsigned int *bin_r_c = data_chunk->bin_r;
	const unsigned int *bin_g_c = data_chunk->bin_g;
	const unsigned int *bin_b_c = data_chunk->bin_b;
	const unsigned int *bin_a_c = data_chunk->bin_a;

	float (*minmax)[2] = data->scopes->minmax;
	const float *min = data_chunk->min;
	const float *max = data_chunk->max;

	for (int b = 256; b--;) {
		bin_lum[b] += bin_lum_c[b];
		bin_r[b] += bin_r_c[b];
		bin_g[b] += bin_g_c[b];
		bin_b[b] += bin_b_c[b];
		bin_a[b] += bin_a_c[b];
	}

	for (int c = 3; c--;) {
		if (min[c] < minmax[c][0])
			minmax[c][0] = min[c];
		if (max[c] > minmax[c][1])
			minmax[c][1] = max[c];
	}
}

void scopes_update(Scopes *scopes, ImBuf *ibuf, const ColorManagedViewSettings *view_settings,
                   const ColorManagedDisplaySettings *display_settings)
{
	int a;
	unsigned int nl, na, nr, ng, nb;
	double divl, diva, divr, divg, divb;
	const unsigned char *display_buffer = NULL;
	unsigned int bin_lum[256] = {0},
	             bin_r[256] = {0},
	             bin_g[256] = {0},
	             bin_b[256] = {0},
	             bin_a[256] = {0};
	int ycc_mode = -1;
	void *cache_handle = NULL;
	struct ColormanageProcessor *cm_processor = NULL;

	if (ibuf->rect == NULL && ibuf->rect_float == NULL) return;

	if (scopes->ok == 1) return;

	if (scopes->hist.ymax == 0.f) scopes->hist.ymax = 1.f;

	/* hmmmm */
	if (!(ELEM(ibuf->channels, 3, 4))) return;

	scopes->hist.channels = 3;
	scopes->hist.x_resolution = 256;

	switch (scopes->wavefrm_mode) {
		case SCOPES_WAVEFRM_RGB:
			/* fall-through */
		case SCOPES_WAVEFRM_RGB_PARADE:
			ycc_mode = -1;
			break;
		case SCOPES_WAVEFRM_LUMA:
		case SCOPES_WAVEFRM_YCC_JPEG:
			ycc_mode = BLI_YCC_JFIF_0_255;
			break;
		case SCOPES_WAVEFRM_YCC_601:
			ycc_mode = BLI_YCC_ITU_BT601;
			break;
		case SCOPES_WAVEFRM_YCC_709:
			ycc_mode = BLI_YCC_ITU_BT709;
			break;
	}

	/* convert to number of lines with logarithmic scale */
	scopes->sample_lines = (scopes->accuracy * 0.01f) * (scopes->accuracy * 0.01f) * ibuf->y;
	CLAMP_MIN(scopes->sample_lines, 1);
	
	if (scopes->sample_full)
		scopes->sample_lines = ibuf->y;

	/* scan the image */
	for (a = 0; a < 3; a++) {
		scopes->minmax[a][0] = 25500.0f;
		scopes->minmax[a][1] = -25500.0f;
	}
	
	scopes->waveform_tot = ibuf->x * scopes->sample_lines;
	
	if (scopes->waveform_1)
		MEM_freeN(scopes->waveform_1);
	if (scopes->waveform_2)
		MEM_freeN(scopes->waveform_2);
	if (scopes->waveform_3)
		MEM_freeN(scopes->waveform_3);
	if (scopes->vecscope)
		MEM_freeN(scopes->vecscope);
	
	scopes->waveform_1 = MEM_callocN(scopes->waveform_tot * 2 * sizeof(float), "waveform point channel 1");
	scopes->waveform_2 = MEM_callocN(scopes->waveform_tot * 2 * sizeof(float), "waveform point channel 2");
	scopes->waveform_3 = MEM_callocN(scopes->waveform_tot * 2 * sizeof(float), "waveform point channel 3");
	scopes->vecscope = MEM_callocN(scopes->waveform_tot * 2 * sizeof(float), "vectorscope point channel");
	
	if (ibuf->rect_float) {
		cm_processor = IMB_colormanagement_display_processor_new(view_settings, display_settings);
	}
	else {
		display_buffer = (const unsigned char *)IMB_display_buffer_acquire(
		                                            ibuf, view_settings, display_settings, &cache_handle);
	}

	/* Keep number of threads in sync with the merge parts below. */
	ScopesUpdateData data = {
		.scopes = scopes, .ibuf = ibuf,
		.cm_processor = cm_processor, .display_buffer = display_buffer, .ycc_mode = ycc_mode,
		.bin_lum = bin_lum, .bin_r = bin_r, .bin_g = bin_g, .bin_b = bin_b, .bin_a = bin_a,
	};
	ScopesUpdateDataChunk data_chunk = {{0}};
	INIT_MINMAX(data_chunk.min, data_chunk.max);

	ParallelRangeSettings settings;
	BLI_parallel_range_settings_defaults(&settings);
	settings.use_threading = (ibuf->y > 256);
	settings.userdata_chunk = &data_chunk;
	settings.userdata_chunk_size = sizeof(data_chunk);
	settings.func_finalize = scopes_update_finalize;
	BLI_task_parallel_range(0, ibuf->y,
	                        &data,
	                        scopes_update_cb,
	                        &settings);

	/* test for nicer distribution even - non standard, leave it out for a while */
#if 0
	for (a = 0; a < 256; a++) {
		bin_lum[a] = sqrt (bin_lum[a]);
		bin_r[a] = sqrt(bin_r[a]);
		bin_g[a] = sqrt(bin_g[a]);
		bin_b[a] = sqrt(bin_b[a]);
		bin_a[a] = sqrt(bin_a[a]);
	}
#endif
	
	/* convert hist data to float (proportional to max count) */
	nl = na = nr = nb = ng = 0;
	for (a = 0; a < 256; a++) {
		if (bin_lum[a] > nl) nl = bin_lum[a];
		if (bin_r[a]   > nr) nr = bin_r[a];
		if (bin_g[a]   > ng) ng = bin_g[a];
		if (bin_b[a]   > nb) nb = bin_b[a];
		if (bin_a[a]   > na) na = bin_a[a];
	}
	divl = nl ? 1.0 / (double)nl : 1.0;
	diva = na ? 1.0 / (double)na : 1.0;
	divr = nr ? 1.0 / (double)nr : 1.0;
	divg = ng ? 1.0 / (double)ng : 1.0;
	divb = nb ? 1.0 / (double)nb : 1.0;
	
	for (a = 0; a < 256; a++) {
		scopes->hist.data_luma[a] = bin_lum[a] * divl;
		scopes->hist.data_r[a] = bin_r[a] * divr;
		scopes->hist.data_g[a] = bin_g[a] * divg;
		scopes->hist.data_b[a] = bin_b[a] * divb;
		scopes->hist.data_a[a] = bin_a[a] * diva;
	}

	if (cm_processor)
		IMB_colormanagement_processor_free(cm_processor);
	if (cache_handle)
		IMB_display_buffer_release(cache_handle);
	
	scopes->ok = 1;
}

void scopes_free(Scopes *scopes)
{
	if (scopes->waveform_1) {
		MEM_freeN(scopes->waveform_1);
		scopes->waveform_1 = NULL;
	}
	if (scopes->waveform_2) {
		MEM_freeN(scopes->waveform_2);
		scopes->waveform_2 = NULL;
	}
	if (scopes->waveform_3) {
		MEM_freeN(scopes->waveform_3);
		scopes->waveform_3 = NULL;
	}
	if (scopes->vecscope) {
		MEM_freeN(scopes->vecscope);
		scopes->vecscope = NULL;
	}
}

void scopes_new(Scopes *scopes)
{
	scopes->accuracy = 30.0;
	scopes->hist.mode = HISTO_MODE_RGB;
	scopes->wavefrm_alpha = 0.3;
	scopes->vecscope_alpha = 0.3;
	scopes->wavefrm_height = 100;
	scopes->vecscope_height = 100;
	scopes->hist.height = 100;
	scopes->ok = 0;
	scopes->waveform_1 = NULL;
	scopes->waveform_2 = NULL;
	scopes->waveform_3 = NULL;
	scopes->vecscope = NULL;
}

void BKE_color_managed_display_settings_init(ColorManagedDisplaySettings *settings)
{
	const char *display_name = IMB_colormanagement_display_get_default_name();

	BLI_strncpy(settings->display_device, display_name, sizeof(settings->display_device));
}

void BKE_color_managed_display_settings_copy(ColorManagedDisplaySettings *new_settings,
                                             const ColorManagedDisplaySettings *settings)
{
	BLI_strncpy(new_settings->display_device, settings->display_device, sizeof(new_settings->display_device));
}

void BKE_color_managed_view_settings_init(ColorManagedViewSettings *settings)
{
	/* OCIO_TODO: use default view transform here when OCIO is completely integrated
	 *            and proper versioning stuff is added.
	 *            for now use NONE to be compatible with all current files
	 */
	BLI_strncpy(settings->view_transform, "Default", sizeof(settings->view_transform));
	BLI_strncpy(settings->look, "None", sizeof(settings->look));

	settings->gamma = 1.0f;
	settings->exposure = 0.0f;
}

void BKE_color_managed_view_settings_copy(ColorManagedViewSettings *new_settings,
                                          const ColorManagedViewSettings *settings)
{
	BLI_strncpy(new_settings->look, settings->look, sizeof(new_settings->look));
	BLI_strncpy(new_settings->view_transform, settings->view_transform, sizeof(new_settings->view_transform));

	new_settings->flag = settings->flag;
	new_settings->exposure = settings->exposure;
	new_settings->gamma = settings->gamma;

	if (settings->curve_mapping)
		new_settings->curve_mapping = curvemapping_copy(settings->curve_mapping);
	else
		new_settings->curve_mapping = NULL;
}

void BKE_color_managed_view_settings_free(ColorManagedViewSettings *settings)
{
	if (settings->curve_mapping)
		curvemapping_free(settings->curve_mapping);
}

void BKE_color_managed_colorspace_settings_init(ColorManagedColorspaceSettings *colorspace_settings)
{
	BLI_strncpy(colorspace_settings->name, "", sizeof(colorspace_settings->name));
}

void BKE_color_managed_colorspace_settings_copy(ColorManagedColorspaceSettings *colorspace_settings,
                                                const ColorManagedColorspaceSettings *settings)
{
	BLI_strncpy(colorspace_settings->name, settings->name, sizeof(colorspace_settings->name));
}

bool BKE_color_managed_colorspace_settings_equals(const ColorManagedColorspaceSettings *settings1,
                                                  const ColorManagedColorspaceSettings *settings2)
{
	return STREQ(settings1->name, settings2->name);
}