blender-archive/source/blender/modifiers/intern/MOD_normal_edit.c

/*
 * 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.
 */

/** \file
 * \ingroup modifiers
 */

#include <string.h>

#include "MEM_guardedalloc.h"

#include "DNA_object_types.h"
#include "DNA_meshdata_types.h"
#include "DNA_mesh_types.h"

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

#include "BKE_library.h"
#include "BKE_library_query.h"
#include "BKE_mesh.h"
#include "BKE_deform.h"

#include "DEG_depsgraph_query.h"

#include "MOD_util.h"


static void generate_vert_coordinates(
        Mesh *mesh, Object *ob, Object *ob_center, const float offset[3],
        const int num_verts, float (*r_cos)[3], float r_size[3])
{
	float min_co[3], max_co[3];
	float diff[3];
	bool do_diff = false;

	INIT_MINMAX(min_co, max_co);

	MVert *mv = mesh->mvert;
	for (int i = 0; i < mesh->totvert; i++, mv++) {
		copy_v3_v3(r_cos[i], mv->co);
		if (r_size != NULL && ob_center == NULL) {
			minmax_v3v3_v3(min_co, max_co, r_cos[i]);
		}
	}

	/* Get size (i.e. deformation of the spheroid generating normals), either from target object, or own geometry. */
	if (r_size != NULL) {
		if (ob_center != NULL) {
			/* Using 'scale' as 'size' here. The input object is typically an empty
			 * who's scale is used to define an ellipsoid instead of a simple sphere. */

			/* Not we are not interested in signs here - they are even troublesome actually, due to security clamping! */
			abs_v3_v3(r_size, ob_center->scale);
		}
		else {
			/* Set size. */
			sub_v3_v3v3(r_size, max_co, min_co);
		}

		/* Error checks - we do not want one or more of our sizes to be null! */
		if (is_zero_v3(r_size)) {
			r_size[0] = r_size[1] = r_size[2] = 1.0f;
		}
		else {
			CLAMP_MIN(r_size[0], FLT_EPSILON);
			CLAMP_MIN(r_size[1], FLT_EPSILON);
			CLAMP_MIN(r_size[2], FLT_EPSILON);
		}
	}

	if (ob_center != NULL) {
		float inv_obmat[4][4];

		/* Translate our coordinates so that center of ob_center is at (0, 0, 0). */
		/* Get ob_center (world) coordinates in ob local coordinates.
		 * No need to take into account ob_center's space here, see T44027. */
		invert_m4_m4(inv_obmat, ob->obmat);
		mul_v3_m4v3(diff, inv_obmat, ob_center->obmat[3]);
		negate_v3(diff);

		do_diff = true;
	}
	else if (offset != NULL && !is_zero_v3(offset)) {
		negate_v3_v3(diff, offset);

		do_diff = true;
	}
	/* Else, no need to change coordinates! */

	if (do_diff) {
		int i = num_verts;
		while (i--) {
			add_v3_v3(r_cos[i], diff);
		}
	}
}

/* Note this modifies nos_new in-place. */
static void mix_normals(
        const float mix_factor, MDeformVert *dvert, const int defgrp_index, const bool use_invert_vgroup,
        const float mix_limit, const short mix_mode,
        const int num_verts, MLoop *mloop, float (*nos_old)[3], float (*nos_new)[3], const int num_loops)
{
	/* Mix with org normals... */
	float *facs = NULL, *wfac;
	float (*no_new)[3], (*no_old)[3];
	int i;

	if (dvert) {
		facs = MEM_malloc_arrayN((size_t)num_loops, sizeof(*facs), __func__);
		BKE_defvert_extract_vgroup_to_loopweights(
		            dvert, defgrp_index, num_verts, mloop, num_loops, facs, use_invert_vgroup);
	}

	for (i = num_loops, no_new = nos_new, no_old = nos_old, wfac = facs; i--; no_new++, no_old++, wfac++) {
		const float fac = facs ? *wfac * mix_factor : mix_factor;

		switch (mix_mode) {
			case MOD_NORMALEDIT_MIX_ADD:
				add_v3_v3(*no_new, *no_old);
				normalize_v3(*no_new);
				break;
			case MOD_NORMALEDIT_MIX_SUB:
				sub_v3_v3(*no_new, *no_old);
				normalize_v3(*no_new);
				break;
			case MOD_NORMALEDIT_MIX_MUL:
				mul_v3_v3(*no_new, *no_old);
				normalize_v3(*no_new);
				break;
			case MOD_NORMALEDIT_MIX_COPY:
				break;
		}

		interp_v3_v3v3_slerp_safe(
		        *no_new, *no_old, *no_new,
		        (mix_limit < (float)M_PI) ? min_ff(fac, mix_limit / angle_v3v3(*no_new, *no_old)) : fac);
	}

	MEM_SAFE_FREE(facs);
}

/* Check poly normals and new loop normals are compatible, otherwise flip polygons
 * (and invert matching poly normals). */
static bool polygons_check_flip(
        MLoop *mloop, float (*nos)[3], CustomData *ldata,
        MPoly *mpoly, float (*polynors)[3], const int num_polys)
{
	MPoly *mp;
	MDisps *mdisp = CustomData_get_layer(ldata, CD_MDISPS);
	int i;
	bool flipped = false;

	for (i = 0, mp = mpoly; i < num_polys; i++, mp++) {
		float norsum[3] = {0.0f};
		float (*no)[3];
		int j;

		for (j = 0, no = &nos[mp->loopstart]; j < mp->totloop; j++, no++) {
			add_v3_v3(norsum, *no);
		}

		if (!normalize_v3(norsum)) {
			continue;
		}

		/* If average of new loop normals is opposed to polygon normal, flip polygon. */
		if (dot_v3v3(polynors[i], norsum) < 0.0f) {
			BKE_mesh_polygon_flip_ex(mp, mloop, ldata, nos, mdisp, true);
			negate_v3(polynors[i]);
			flipped = true;
		}
	}

	return flipped;
}

static void normalEditModifier_do_radial(
        NormalEditModifierData *enmd, const ModifierEvalContext *ctx,
        Object *ob, Mesh *mesh,
        short (*clnors)[2], float (*loopnors)[3], float (*polynors)[3],
        const short mix_mode, const float mix_factor, const float mix_limit,
        MDeformVert *dvert, const int defgrp_index, const bool use_invert_vgroup,
        MVert *mvert, const int num_verts, MEdge *medge, const int num_edges,
        MLoop *mloop, const int num_loops, MPoly *mpoly, const int num_polys)
{
	Object *ob_target = DEG_get_evaluated_object(ctx->depsgraph, enmd->target);

	const bool do_polynors_fix = (enmd->flag & MOD_NORMALEDIT_NO_POLYNORS_FIX) == 0;
	int i;

	float (*cos)[3] = MEM_malloc_arrayN((size_t)num_verts, sizeof(*cos), __func__);
	float (*nos)[3] = MEM_malloc_arrayN((size_t)num_loops, sizeof(*nos), __func__);
	float size[3];

	BLI_bitmap *done_verts = BLI_BITMAP_NEW((size_t)num_verts, __func__);

	generate_vert_coordinates(mesh, ob, ob_target, enmd->offset, num_verts, cos, size);

	/**
	 * size gives us our spheroid coefficients ``(A, B, C)``.
	 * Then, we want to find out for each vert its (a, b, c) triple (proportional to (A, B, C) one).
	 *
	 * Ellipsoid basic equation: ``(x^2/a^2) + (y^2/b^2) + (z^2/c^2) = 1.``
	 * Since we want to find (a, b, c) matching this equation and proportional to (A, B, C), we can do:
	 * <pre>
	 *     m = B / A
	 *     n = C / A
	 * </pre>
	 *
	 * hence:
	 * <pre>
	 *     (x^2/a^2) + (y^2/b^2) + (z^2/c^2) = 1
	 *  -> b^2*c^2*x^2 + a^2*c^2*y^2 + a^2*b^2*z^2 = a^2*b^2*c^2
	 *     b = ma
	 *     c = na
	 *  -> m^2*a^2*n^2*a^2*x^2 + a^2*n^2*a^2*y^2 + a^2*m^2*a^2*z^2 = a^2*m^2*a^2*n^2*a^2
	 *  -> m^2*n^2*a^4*x^2 + n^2*a^4*y^2 + m^2*a^4*z^2 = m^2*n^2*a^6
	 *  -> a^2 = (m^2*n^2*x^2 + n^2y^2 + m^2z^2) / (m^2*n^2) = x^2 + (y^2 / m^2) + (z^2 / n^2)
	 *  -> b^2 = (m^2*n^2*x^2 + n^2y^2 + m^2z^2) / (n^2)     = (m^2 * x^2) + y^2 + (m^2 * z^2 / n^2)
	 *  -> c^2 = (m^2*n^2*x^2 + n^2y^2 + m^2z^2) / (m^2)     = (n^2 * x^2) + (n^2 * y^2 / m^2) + z^2
	 * </pre>
	 *
	 * All we have to do now is compute normal of the spheroid at that point:
	 * <pre>
	 *     n = (x / a^2, y / b^2, z / c^2)
	 * </pre>
	 * And we are done!
	 */
	{
		const float a = size[0], b = size[1], c = size[2];
		const float m2 = (b * b) / (a * a);
		const float n2 = (c * c) / (a * a);

		MLoop *ml;
		float (*no)[3];

		/* We reuse cos to now store the ellipsoid-normal of the verts! */
		for (i = num_loops, ml = mloop, no = nos; i-- ; ml++, no++) {
			const int vidx = ml->v;
			float *co = cos[vidx];

			if (!BLI_BITMAP_TEST(done_verts, vidx)) {
				const float x2 = co[0] * co[0];
				const float y2 = co[1] * co[1];
				const float z2 = co[2] * co[2];
				const float a2 = x2 + (y2 / m2) + (z2 / n2);
				const float b2 = (m2 * x2) + y2 + (m2 * z2 / n2);
				const float c2 = (n2 * x2) + (n2 * y2 / m2) + z2;

				co[0] /= a2;
				co[1] /= b2;
				co[2] /= c2;
				normalize_v3(co);

				BLI_BITMAP_ENABLE(done_verts, vidx);
			}
			copy_v3_v3(*no, co);
		}
	}

	if (loopnors) {
		mix_normals(mix_factor, dvert, defgrp_index, use_invert_vgroup,
		            mix_limit, mix_mode, num_verts, mloop, loopnors, nos, num_loops);
	}

	if (do_polynors_fix && polygons_check_flip(mloop, nos, &mesh->ldata, mpoly, polynors, num_polys)) {
		/* XXX TODO is this still needed? */
		// mesh->dirty |= DM_DIRTY_TESS_CDLAYERS;
		/* We need to recompute vertex normals! */
		BKE_mesh_calc_normals(mesh);
	}

	BKE_mesh_normals_loop_custom_set(mvert, num_verts, medge, num_edges, mloop, nos, num_loops,
	                                 mpoly, (const float(*)[3])polynors, num_polys, clnors);

	MEM_freeN(cos);
	MEM_freeN(nos);
	MEM_freeN(done_verts);
}

static void normalEditModifier_do_directional(
        NormalEditModifierData *enmd, const ModifierEvalContext *ctx,
        Object *ob, Mesh *mesh,
        short (*clnors)[2], float (*loopnors)[3], float (*polynors)[3],
        const short mix_mode, const float mix_factor, const float mix_limit,
        MDeformVert *dvert, const int defgrp_index, const bool use_invert_vgroup,
        MVert *mvert, const int num_verts, MEdge *medge, const int num_edges,
        MLoop *mloop, const int num_loops, MPoly *mpoly, const int num_polys)
{
	Object *ob_target = DEG_get_evaluated_object(ctx->depsgraph, enmd->target);

	const bool do_polynors_fix = (enmd->flag & MOD_NORMALEDIT_NO_POLYNORS_FIX) == 0;
	const bool use_parallel_normals = (enmd->flag & MOD_NORMALEDIT_USE_DIRECTION_PARALLEL) != 0;

	float (*nos)[3] = MEM_malloc_arrayN((size_t)num_loops, sizeof(*nos), __func__);

	float target_co[3];
	int i;

	/* Get target's center coordinates in ob local coordinates. */
	float mat[4][4];

	invert_m4_m4(mat, ob->obmat);
	mul_m4_m4m4(mat, mat, ob_target->obmat);
	copy_v3_v3(target_co, mat[3]);

	if (use_parallel_normals) {
		float no[3];

		sub_v3_v3v3(no, target_co, enmd->offset);
		normalize_v3(no);

		for (i = num_loops; i--; ) {
			copy_v3_v3(nos[i], no);
		}
	}
	else {
		float (*cos)[3] = MEM_malloc_arrayN((size_t)num_verts, sizeof(*cos), __func__);
		generate_vert_coordinates(mesh, ob, ob_target, NULL, num_verts, cos, NULL);

		BLI_bitmap *done_verts = BLI_BITMAP_NEW((size_t)num_verts, __func__);
		MLoop *ml;
		float (*no)[3];

		/* We reuse cos to now store the 'to target' normal of the verts! */
		for (i = num_loops, no = nos, ml = mloop; i--; no++, ml++) {
			const int vidx = ml->v;
			float *co = cos[vidx];

			if (!BLI_BITMAP_TEST(done_verts, vidx)) {
				sub_v3_v3v3(co, target_co, co);
				normalize_v3(co);

				BLI_BITMAP_ENABLE(done_verts, vidx);
			}

			copy_v3_v3(*no, co);
		}

		MEM_freeN(done_verts);
		MEM_freeN(cos);
	}

	if (loopnors) {
		mix_normals(mix_factor, dvert, defgrp_index, use_invert_vgroup,
		            mix_limit, mix_mode, num_verts, mloop, loopnors, nos, num_loops);
	}

	if (do_polynors_fix && polygons_check_flip(mloop, nos, &mesh->ldata, mpoly, polynors, num_polys)) {
		mesh->runtime.cd_dirty_vert |= CD_MASK_NORMAL;
	}

	BKE_mesh_normals_loop_custom_set(mvert, num_verts, medge, num_edges, mloop, nos, num_loops,
	                                 mpoly, (const float(*)[3])polynors, num_polys, clnors);

	MEM_freeN(nos);
}

static bool is_valid_target(NormalEditModifierData *enmd)
{
	if (enmd->mode == MOD_NORMALEDIT_MODE_RADIAL) {
		return true;
	}
	else if ((enmd->mode == MOD_NORMALEDIT_MODE_DIRECTIONAL) && enmd->target) {
		return true;
	}
	modifier_setError((ModifierData *)enmd, "Invalid target settings");
	return false;
}

static Mesh *normalEditModifier_do(
        NormalEditModifierData *enmd, const ModifierEvalContext *ctx, Object *ob, Mesh *mesh)
{
	const bool use_invert_vgroup = ((enmd->flag & MOD_NORMALEDIT_INVERT_VGROUP) != 0);
	const bool use_current_clnors = !((enmd->mix_mode == MOD_NORMALEDIT_MIX_COPY) &&
	                                  (enmd->mix_factor == 1.0f) &&
	                                  (enmd->defgrp_name[0] == '\0') &&
	                                  (enmd->mix_limit == (float)M_PI));

	/* Do not run that modifier at all if autosmooth is disabled! */
	if (!is_valid_target(enmd) || mesh->totloop == 0) {
		return mesh;
	}

	/* XXX TODO ARG GRRR XYQWNMPRXTYY
	 * Once we fully switch to Mesh evaluation of modifiers, we can expect to get that flag from the COW copy.
	 * But for now, it is lost in the DM intermediate step, so we need to directly check orig object's data. */
#if 0
	if (!(mesh->flag & ME_AUTOSMOOTH)) {
#else
	if (!(((Mesh *)ob->data)->flag & ME_AUTOSMOOTH)) {
#endif
		modifier_setError((ModifierData *)enmd, "Enable 'Auto Smooth' option in mesh settings");
		return mesh;
	}

	Mesh *result;
	if (mesh->medge == ((Mesh *)ob->data)->medge) {
		/* We need to duplicate data here, otherwise setting custom normals (which may also affect sharp edges) could
		 * modify org mesh, see T43671. */
		BKE_id_copy_ex(NULL, &mesh->id, (ID **)&result, LIB_ID_COPY_LOCALIZE);
	}
	else {
		result = mesh;
	}

	const int num_verts = result->totvert;
	const int num_edges = result->totedge;
	const int num_loops = result->totloop;
	const int num_polys = result->totpoly;
	MVert *mvert = result->mvert;
	MEdge *medge = result->medge;
	MLoop *mloop = result->mloop;
	MPoly *mpoly = result->mpoly;

	int defgrp_index;
	MDeformVert *dvert;

	float (*loopnors)[3] = NULL;
	short (*clnors)[2] = NULL;

	float (*polynors)[3];

	CustomData *ldata = &result->ldata;
	if (CustomData_has_layer(ldata, CD_NORMAL)) {
		loopnors = CustomData_get_layer(ldata, CD_NORMAL);
	}
	else {
		loopnors = CustomData_add_layer(ldata, CD_NORMAL, CD_CALLOC, NULL, num_loops);
	}

	/* Compute poly (always needed) and vert normals. */
	CustomData *pdata = &result->pdata;
	polynors = CustomData_get_layer(pdata, CD_NORMAL);
	if (!polynors) {
		polynors = CustomData_add_layer(pdata, CD_NORMAL, CD_CALLOC, NULL, num_polys);
	}
	BKE_mesh_calc_normals_poly(mvert, NULL, num_verts, mloop, mpoly, num_loops, num_polys, polynors,
	                           (result->runtime.cd_dirty_vert & CD_MASK_NORMAL) ? false : true);

	result->runtime.cd_dirty_vert &= ~CD_MASK_NORMAL;

	if (use_current_clnors) {
		clnors = CustomData_duplicate_referenced_layer(ldata, CD_CUSTOMLOOPNORMAL, num_loops);

		BKE_mesh_normals_loop_split(mvert, num_verts, medge, num_edges, mloop, loopnors, num_loops,
		                            mpoly, (const float (*)[3])polynors, num_polys,
		                            true, result->smoothresh,
		                            NULL, clnors, NULL);
	}

	if (!clnors) {
		clnors = CustomData_add_layer(ldata, CD_CUSTOMLOOPNORMAL, CD_CALLOC, NULL, num_loops);
	}

	MOD_get_vgroup(ob, result, enmd->defgrp_name, &dvert, &defgrp_index);

	if (enmd->mode == MOD_NORMALEDIT_MODE_RADIAL) {
		normalEditModifier_do_radial(
		            enmd, ctx, ob, result, clnors, loopnors, polynors,
		            enmd->mix_mode, enmd->mix_factor, enmd->mix_limit, dvert, defgrp_index, use_invert_vgroup,
		            mvert, num_verts, medge, num_edges, mloop, num_loops, mpoly, num_polys);
	}
	else if (enmd->mode == MOD_NORMALEDIT_MODE_DIRECTIONAL) {
		normalEditModifier_do_directional(
		            enmd, ctx, ob, result, clnors, loopnors, polynors,
		            enmd->mix_mode, enmd->mix_factor, enmd->mix_limit, dvert, defgrp_index, use_invert_vgroup,
		            mvert, num_verts, medge, num_edges, mloop, num_loops, mpoly, num_polys);
	}

	return result;
}

static void initData(ModifierData *md)
{
	NormalEditModifierData *enmd = (NormalEditModifierData *)md;

	enmd->mode = MOD_NORMALEDIT_MODE_RADIAL;

	enmd->mix_mode = MOD_NORMALEDIT_MIX_COPY;
	enmd->mix_factor = 1.0f;
	enmd->mix_limit = M_PI;
}

static CustomDataMask requiredDataMask(Object *UNUSED(ob), ModifierData *md)
{
	NormalEditModifierData *enmd = (NormalEditModifierData *)md;
	CustomDataMask dataMask = CD_MASK_CUSTOMLOOPNORMAL;

	/* Ask for vertexgroups if we need them. */
	if (enmd->defgrp_name[0]) {
		dataMask |= (CD_MASK_MDEFORMVERT);
	}

	return dataMask;
}

static bool dependsOnNormals(ModifierData *UNUSED(md))
{
	return true;
}

static void foreachObjectLink(ModifierData *md, Object *ob, ObjectWalkFunc walk, void *userData)
{
	NormalEditModifierData *enmd = (NormalEditModifierData *) md;

	walk(userData, ob, &enmd->target, IDWALK_CB_NOP);
}

static bool isDisabled(const struct Scene *UNUSED(scene), ModifierData *md, bool UNUSED(useRenderParams))
{
	NormalEditModifierData *enmd = (NormalEditModifierData *)md;

	return !is_valid_target(enmd);
}

static void updateDepsgraph(ModifierData *md, const ModifierUpdateDepsgraphContext *ctx)
{
	NormalEditModifierData *enmd = (NormalEditModifierData *) md;
	if (enmd->target) {
		DEG_add_object_relation(ctx->node, enmd->target, DEG_OB_COMP_TRANSFORM, "NormalEdit Modifier");
		DEG_add_modifier_to_transform_relation(ctx->node, "NormalEdit Modifier");
	}
}

static Mesh *applyModifier(ModifierData *md, const ModifierEvalContext *ctx, Mesh *mesh)
{
	return normalEditModifier_do((NormalEditModifierData *)md, ctx, ctx->object, mesh);
}

ModifierTypeInfo modifierType_NormalEdit = {
	/* name */              "Set Split Normals",
	/* structName */        "NormalEditModifierData",
	/* structSize */        sizeof(NormalEditModifierData),
	/* type */              eModifierTypeType_Constructive,
	/* flags */             eModifierTypeFlag_AcceptsMesh |
	                        eModifierTypeFlag_SupportsMapping |
	                        eModifierTypeFlag_SupportsEditmode |
	                        eModifierTypeFlag_EnableInEditmode,

	/* copyData */          modifier_copyData_generic,

	/* deformVerts_DM */    NULL,
	/* deformMatrices_DM */ NULL,
	/* deformVertsEM_DM */  NULL,
	/* deformMatricesEM_DM*/NULL,
	/* applyModifier_DM */  NULL,

	/* deformVerts */       NULL,
	/* deformMatrices */    NULL,
	/* deformVertsEM */     NULL,
	/* deformMatricesEM */  NULL,
	/* applyModifier */     applyModifier,

	/* initData */          initData,
	/* requiredDataMask */  requiredDataMask,
	/* freeData */          NULL,
	/* isDisabled */        isDisabled,
	/* updateDepsgraph */   updateDepsgraph,
	/* dependsOnTime */     NULL,
	/* dependsOnNormals */  dependsOnNormals,
	/* foreachObjectLink */ foreachObjectLink,
	/* foreachIDLink */     NULL,
	/* foreachTexLink */    NULL,
};