path: root/source/blender/modifiers/intern/MOD_subsurf.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.
 *
 * The Original Code is Copyright (C) 2005 by the Blender Foundation.
 * All rights reserved.
 */

/** \file
 * \ingroup modifiers
 */

#include <stddef.h>

#include "MEM_guardedalloc.h"

#include "BLI_utildefines.h"

#include "DNA_object_types.h"
#include "DNA_scene_types.h"
#include "DNA_mesh_types.h"

#include "BKE_cdderivedmesh.h"
#include "BKE_scene.h"
#include "BKE_subdiv.h"
#include "BKE_subdiv_ccg.h"
#include "BKE_subdiv_deform.h"
#include "BKE_subdiv_mesh.h"
#include "BKE_subsurf.h"

#include "DEG_depsgraph.h"
#include "DEG_depsgraph_query.h"

#include "MOD_modifiertypes.h"

#include "intern/CCGSubSurf.h"

typedef struct SubsurfRuntimeData {
  /* Cached subdivision surface descriptor, with topology and settings. */
  struct Subdiv *subdiv;
} SubsurfRuntimeData;

static void initData(ModifierData *md)
{
  SubsurfModifierData *smd = (SubsurfModifierData *)md;

  smd->levels = 1;
  smd->renderLevels = 2;
  smd->uv_smooth = SUBSURF_UV_SMOOTH_PRESERVE_CORNERS;
  smd->quality = 3;
  smd->flags |= eSubsurfModifierFlag_UseCrease;
}

static void copyData(const ModifierData *md, ModifierData *target, const int flag)
{
#if 0
  const SubsurfModifierData *smd = (const SubsurfModifierData *)md;
#endif
  SubsurfModifierData *tsmd = (SubsurfModifierData *)target;

  modifier_copyData_generic(md, target, flag);

  tsmd->emCache = tsmd->mCache = NULL;
}

static void freeRuntimeData(void *runtime_data_v)
{
  if (runtime_data_v == NULL) {
    return;
  }
  SubsurfRuntimeData *runtime_data = (SubsurfRuntimeData *)runtime_data_v;
  if (runtime_data->subdiv != NULL) {
    BKE_subdiv_free(runtime_data->subdiv);
  }
  MEM_freeN(runtime_data);
}

static void freeData(ModifierData *md)
{
  SubsurfModifierData *smd = (SubsurfModifierData *)md;

  if (smd->mCache) {
    ccgSubSurf_free(smd->mCache);
    smd->mCache = NULL;
  }
  if (smd->emCache) {
    ccgSubSurf_free(smd->emCache);
    smd->emCache = NULL;
  }
  freeRuntimeData(smd->modifier.runtime);
}

static bool isDisabled(const Scene *scene, ModifierData *md, bool useRenderParams)
{
  SubsurfModifierData *smd = (SubsurfModifierData *)md;
  int levels = (useRenderParams) ? smd->renderLevels : smd->levels;

  return get_render_subsurf_level(&scene->r, levels, useRenderParams != 0) == 0;
}

static int subdiv_levels_for_modifier_get(const SubsurfModifierData *smd,
                                          const ModifierEvalContext *ctx)
{
  Scene *scene = DEG_get_evaluated_scene(ctx->depsgraph);
  const bool use_render_params = (ctx->flag & MOD_APPLY_RENDER);
  const int requested_levels = (use_render_params) ? smd->renderLevels : smd->levels;
  return get_render_subsurf_level(&scene->r, requested_levels, use_render_params);
}

static void subdiv_settings_init(SubdivSettings *settings, const SubsurfModifierData *smd)
{
  settings->is_simple = (smd->subdivType == SUBSURF_TYPE_SIMPLE);
  settings->is_adaptive = true;
  settings->level = settings->is_simple ? 1 : smd->quality;
  settings->use_creases = (smd->flags & eSubsurfModifierFlag_UseCrease);
  settings->vtx_boundary_interpolation = SUBDIV_VTX_BOUNDARY_EDGE_ONLY;
  settings->fvar_linear_interpolation = BKE_subdiv_fvar_interpolation_from_uv_smooth(
      smd->uv_smooth);
}

/* Main goal of this function is to give usable subdivision surface descriptor
 * which matches settings and topology. */
static Subdiv *subdiv_descriptor_ensure(SubsurfModifierData *smd,
                                        const SubdivSettings *subdiv_settings,
                                        const Mesh *mesh)
{
  SubsurfRuntimeData *runtime_data = (SubsurfRuntimeData *)smd->modifier.runtime;
  Subdiv *subdiv = BKE_subdiv_update_from_mesh(runtime_data->subdiv, subdiv_settings, mesh);
  runtime_data->subdiv = subdiv;
  return subdiv;
}

/* Subdivide into fully qualified mesh. */

static void subdiv_mesh_settings_init(SubdivToMeshSettings *settings,
                                      const SubsurfModifierData *smd,
                                      const ModifierEvalContext *ctx)
{
  const int level = subdiv_levels_for_modifier_get(smd, ctx);
  settings->resolution = (1 << level) + 1;
  settings->use_optimal_display = (smd->flags & eSubsurfModifierFlag_ControlEdges);
}

static Mesh *subdiv_as_mesh(SubsurfModifierData *smd,
                            const ModifierEvalContext *ctx,
                            Mesh *mesh,
                            Subdiv *subdiv)
{
  Mesh *result = mesh;
  SubdivToMeshSettings mesh_settings;
  subdiv_mesh_settings_init(&mesh_settings, smd, ctx);
  if (mesh_settings.resolution < 3) {
    return result;
  }
  result = BKE_subdiv_to_mesh(subdiv, &mesh_settings, mesh);
  return result;
}

/* Subdivide into CCG. */

static void subdiv_ccg_settings_init(SubdivToCCGSettings *settings,
                                     const SubsurfModifierData *smd,
                                     const ModifierEvalContext *ctx)
{
  const int level = subdiv_levels_for_modifier_get(smd, ctx);
  settings->resolution = (1 << level) + 1;
  settings->need_normal = true;
  settings->need_mask = false;
}

static Mesh *subdiv_as_ccg(SubsurfModifierData *smd,
                           const ModifierEvalContext *ctx,
                           Mesh *mesh,
                           Subdiv *subdiv)
{
  Mesh *result = mesh;
  SubdivToCCGSettings ccg_settings;
  subdiv_ccg_settings_init(&ccg_settings, smd, ctx);
  if (ccg_settings.resolution < 3) {
    return result;
  }
  result = BKE_subdiv_to_ccg_mesh(subdiv, &ccg_settings, mesh);
  return result;
}

static SubsurfRuntimeData *subsurf_ensure_runtime(SubsurfModifierData *smd)
{
  SubsurfRuntimeData *runtime_data = (SubsurfRuntimeData *)smd->modifier.runtime;
  if (runtime_data == NULL) {
    runtime_data = MEM_callocN(sizeof(*runtime_data), "subsurf runtime");
    smd->modifier.runtime = runtime_data;
  }
  return runtime_data;
}

/* Modifier itself. */

static Mesh *applyModifier(ModifierData *md, const ModifierEvalContext *ctx, Mesh *mesh)
{
  Mesh *result = mesh;
#if !defined(WITH_OPENSUBDIV)
  modifier_setError(md, "Disabled, built without OpenSubdiv");
  return result;
#endif
  SubsurfModifierData *smd = (SubsurfModifierData *)md;
  SubdivSettings subdiv_settings;
  subdiv_settings_init(&subdiv_settings, smd);
  if (subdiv_settings.level == 0) {
    return result;
  }
  BKE_subdiv_settings_validate_for_mesh(&subdiv_settings, mesh);
  SubsurfRuntimeData *runtime_data = subsurf_ensure_runtime(smd);
  Subdiv *subdiv = subdiv_descriptor_ensure(smd, &subdiv_settings, mesh);
  if (subdiv == NULL) {
    /* Happens on bad topology, but also on empty input mesh. */
    return result;
  }
  /* TODO(sergey): Decide whether we ever want to use CCG for subsurf,
   * maybe when it is a last modifier in the stack? */
  if (true) {
    result = subdiv_as_mesh(smd, ctx, mesh, subdiv);
  }
  else {
    result = subdiv_as_ccg(smd, ctx, mesh, subdiv);
  }
  // BKE_subdiv_stats_print(&subdiv->stats);
  if (subdiv != runtime_data->subdiv) {
    BKE_subdiv_free(subdiv);
  }
  return result;
}

static void deformVerts(ModifierData *md,
                        const ModifierEvalContext *UNUSED(ctx),
                        Mesh *mesh,
                        float (*vertex_cos)[3],
                        int num_verts)
{
#if !defined(WITH_OPENSUBDIV)
  modifier_setError(md, "Disabled, built without OpenSubdiv");
  return;
#endif
  SubsurfModifierData *smd = (SubsurfModifierData *)md;
  SubdivSettings subdiv_settings;
  subdiv_settings_init(&subdiv_settings, smd);
  if (subdiv_settings.level == 0) {
    return;
  }
  BKE_subdiv_settings_validate_for_mesh(&subdiv_settings, mesh);
  SubsurfRuntimeData *runtime_data = subsurf_ensure_runtime(smd);
  Subdiv *subdiv = subdiv_descriptor_ensure(smd, &subdiv_settings, mesh);
  if (subdiv == NULL) {
    /* Happens on bad topology, but also on empty input mesh. */
    return;
  }
  BKE_subdiv_deform_coarse_vertices(subdiv, mesh, vertex_cos, num_verts);
  if (subdiv != runtime_data->subdiv) {
    BKE_subdiv_free(subdiv);
  }
}

ModifierTypeInfo modifierType_Subsurf = {
    /* name */ "Subdivision",
    /* structName */ "SubsurfModifierData",
    /* structSize */ sizeof(SubsurfModifierData),
    /* type */ eModifierTypeType_Constructive,
    /* flags */ eModifierTypeFlag_AcceptsMesh | eModifierTypeFlag_SupportsMapping |
        eModifierTypeFlag_SupportsEditmode | eModifierTypeFlag_EnableInEditmode |
        eModifierTypeFlag_AcceptsCVs,

    /* copyData */ copyData,

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

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