text: /**
   * libpsd - Photoshop file formats (*.psd) decode library
   * Copyright (C) 2004-2007 Graphest Software.
   *
   * libpsd is the legal property of its developers, whose names are too numerous
   * to list here.  Please refer to the COPYRIGHT file distributed with this
   * source distribution.
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU Library 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 Library General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   *
   * $Id: effects.c, created by Patrick in 2006.05.23, libpsd@graphest.com Exp $
   */
  
  #include "libpsd.h"
  #include "psd_config.h"
  #include "psd_system.h"
  #include "psd_stream.h"
  #include "psd_color.h"
  #include "psd_rect.h"
  #include "psd_bitmap.h"
  #include "psd_math.h"
  #include "psd_descriptor.h"
  
  
  extern psd_status psd_get_layer_drop_shadow(psd_context * context, psd_layer_effects_drop_shadow * drop_shadow);
  extern psd_status psd_get_layer_drop_shadow2(psd_context * context, psd_layer_effects_drop_shadow * drop_shadow);
  extern psd_status psd_get_layer_inner_shadow(psd_context * context, psd_layer_effects_inner_shadow * inner_shadow);
  extern psd_status psd_get_layer_inner_shadow2(psd_context * context, psd_layer_effects_inner_shadow * inner_shadow);
  extern psd_status psd_get_layer_outer_glow(psd_context * context, psd_layer_effects_outer_glow * outer_glow);
  extern psd_status psd_get_layer_outer_glow2(psd_context * context, psd_layer_effects_outer_glow * outer_glow);
  extern psd_status psd_get_layer_inner_glow(psd_context * context, psd_layer_effects_inner_glow * inner_glow);
  extern psd_status psd_get_layer_inner_glow2(psd_context * context, psd_layer_effects_inner_glow * inner_glow);
  extern psd_status psd_get_layer_bevel_emboss(psd_context * context, psd_layer_effects_bevel_emboss * bevel_emboss);
  extern psd_status psd_get_layer_bevel_emboss2(psd_context * context, psd_layer_effects_bevel_emboss * bevel_emboss);
  extern psd_status psd_get_layer_color_overlay(psd_context * context, psd_layer_effects_color_overlay * color_overlay);
  extern psd_status psd_get_layer_color_overlay2(psd_context * context, psd_layer_effects_color_overlay * color_overlay);
  extern psd_status psd_get_layer_gradient_overlay2(psd_context * context, psd_layer_effects_gradient_overlay * gradient_overlay);
  extern psd_status psd_get_layer_pattern_overlay2(psd_context * context, psd_layer_effects_pattern_overlay * pattern_overlay);
  extern psd_status psd_get_layer_stroke2(psd_context * context, psd_layer_effects_stroke * stroke);
  extern psd_status psd_get_layer_satin2(psd_context * context, psd_layer_effects_satin * satin);
  extern psd_status psd_layer_effects_blend_drop_shadow(psd_context * context, psd_layer_record * layer, psd_layer_effects * data);
  extern psd_status psd_layer_effects_blend_inner_shadow(psd_context * context, psd_layer_record * layer, psd_layer_effects * data);
  extern psd_status psd_layer_effects_blend_outer_glow(psd_context * context, psd_layer_record * layer, psd_layer_effects * data);
  extern psd_status psd_layer_effects_blend_inner_glow(psd_context * context, psd_layer_record * layer, psd_layer_effects * data);
  extern psd_status psd_layer_effects_blend_satin(psd_context * context, psd_layer_record * layer, psd_layer_effects * data);
  extern psd_status psd_layer_effects_blend_color_overlay(psd_context * context, psd_layer_record * layer, psd_layer_effects * data);
  extern psd_status psd_layer_effects_blend_gradient_overlay(psd_context * context, psd_layer_record * layer, psd_layer_effects * data);
  extern psd_status psd_layer_effects_blend_pattern_overlay(psd_context * context, psd_layer_record * layer, psd_layer_effects * data);
  extern psd_status psd_layer_effects_blend_stroke(psd_context * context, psd_layer_record * layer, psd_layer_effects * data);
  extern psd_status psd_layer_effects_blend_bevel_emboss(psd_context * context, psd_layer_record * layer, psd_layer_effects * data);
  extern psd_bool psd_layer_check_restricted(psd_context * context, psd_layer_record * layer);
  extern void psd_layer_blend_normal(psd_context * context, psd_layer_record * layer, psd_rect * dst_rect);
  extern void psd_layer_blend(psd_context * context, psd_layer_record * layer, psd_rect * dst_rect);
  extern void psd_layer_blend_normal_restricted(psd_context * context, psd_layer_record * layer, psd_rect * dst_rect);
  extern void psd_layer_blend_restricted(psd_context * context, psd_layer_record * layer, psd_rect * dst_rect);
  
  
  // Effects Layer (Photoshop 5.0)
  psd_status psd_get_layer_effects(psd_context * context, psd_layer_record * layer)
  {
      psd_layer_effects * data;
      psd_int i, size;
      psd_uint tag;
      
      layer->layer_info_type[layer->layer_info_count] = psd_layer_info_type_effects;
      
      data = (psd_layer_effects *)psd_malloc(sizeof(psd_layer_effects));
      if(data == NULL)
          return psd_status_malloc_failed;
      memset(data, 0, sizeof(psd_layer_effects));
      layer->layer_info_data[layer->layer_info_count] = (psd_ptr)(void *)data;
      layer->layer_info_count ++;
      
      // Version: 0
      if(psd_stream_get_short(context) != 0)
          return psd_status_effects_unsupport_version;
      
      // Effects count: may be 6 (for the 6 effects in Photoshop 5 and 6) or 7 (for
      // Photoshop 7.0)
      data->effects_count = psd_stream_get_short(context);
      
      for(i = 0; i < data->effects_count; i ++)
      {
          // Signature: '8BIM'
          tag = psd_stream_get_int(context);
          if(tag != '8BIM')
              return psd_status_effects_signature_error;
          
          // Effects signatures
          tag = psd_stream_get_int(context);
          switch(tag)
          {
              case 'cmnS':	// common state
                  // Effects layer, common state info
                  // Size of next three items: 7
                  size = psd_stream_get_int(context);
                  psd_assert(size == 7);
                  // Version: 0
                  if(psd_stream_get_int(context) != 0)
                      return psd_status_common_state_unsupport_version;
                  // Visible: always psd_true
                  data->visible = psd_stream_get_bool(context);
                  // Unused: always 0
                  psd_stream_get_short(context);
                  break;
                  
              case 'dsdw':	// drop shadow
                  psd_get_layer_drop_shadow(context, &data->drop_shadow);
                  data->fill[psd_layer_effects_type_drop_shadow] = psd_true;
                  data->valid[psd_layer_effects_type_drop_shadow] = psd_true;
                  break;
              case 'isdw':	// inner shadow
                  psd_get_layer_inner_shadow(context, &data->inner_shadow);
                  data->fill[psd_layer_effects_type_inner_shadow] = psd_true;
                  data->valid[psd_layer_effects_type_inner_shadow] = psd_true;
                  break;
              case 'oglw':	// outer glow
                  psd_get_layer_outer_glow(context, &data->outer_glow);
                  data->fill[psd_layer_effects_type_outer_glow] = psd_true;
                  data->valid[psd_layer_effects_type_outer_glow] = psd_true;
                  break;
              case 'iglw':	// inner glow
                  psd_get_layer_inner_glow(context, &data->inner_glow);
                  data->fill[psd_layer_effects_type_inner_glow] = psd_true;
                  data->valid[psd_layer_effects_type_inner_glow] = psd_true;
                  break;
              case 'bevl':	// bevel
                  psd_get_layer_bevel_emboss(context, &data->bevel_emboss);
                  data->fill[psd_layer_effects_type_bevel_emboss] = psd_true;
                  data->valid[psd_layer_effects_type_bevel_emboss] = psd_true;
                  break;
              case 'sofi':	// solid fill (Photoshop 7.0)
                  psd_get_layer_color_overlay(context, &data->color_overlay);
                  data->fill[psd_layer_effects_type_color_overlay] = psd_true;
                  data->valid[psd_layer_effects_type_color_overlay] = psd_true;
                  break;
                  
              default:
                  psd_assert(0);
                  return psd_status_unsupport_effects_type;
          }
      }
      
      return psd_status_done;
  }
  
  // Object-based effects layer info (Photoshop 6.0)
  psd_status psd_get_layer_effects2(psd_context * context, psd_layer_record * layer)
  {
      psd_layer_effects * data;
      psd_int length, number_items;
      psd_uint rootkey, type, key;
      psd_char keychar[256];
      
      layer->layer_info_type[layer->layer_info_count] = psd_layer_info_type_effects2;
      
      data = (psd_layer_effects *)psd_malloc(sizeof(psd_layer_effects));
      if(data == NULL)
          return psd_status_malloc_failed;
      memset(data, 0, sizeof(psd_layer_effects));
      layer->layer_info_data[layer->layer_info_count] = (psd_ptr)(void *)data;
      layer->layer_info_count ++;
      
      // Object effects version: 0
      if(psd_stream_get_int(context) != 0)
          return psd_status_effects_unsupport_version;
      
      // Descriptor version ( = 16 for Photoshop 6.0).
      if(psd_stream_get_int(context) != 16)
          return psd_status_effects_unsupport_version;
      
      // Unicode string: name from classID
      length = psd_stream_get_int(context) * 2;
      psd_stream_get_null(context, length);
      
      // classID: 4 bytes (length), followed either by string or (if length is zero) 4-
      // byte classID
      length = psd_stream_get_int(context);
      if(length == 0)
          psd_stream_get_int(context);
      else
          psd_stream_get_null(context, length);
      
      // Number of items in descriptor
      number_items = psd_stream_get_int(context);
      
      while(number_items--)
      {
          length = psd_stream_get_int(context);
          if(length == 0)
              rootkey = psd_stream_get_int(context);
          else
          {
              rootkey = 0;
              psd_stream_get(context, (psd_uchar*)(keychar), length);
              keychar[length] = 0;
          }
          // Type: OSType key
          type = psd_stream_get_int(context);
          
          switch(rootkey)
          {
              case 0:
                  // pattern overlay
                  if(strcmp(keychar, "patternFill") == 0)
                  {
                      // Descriptor
                      psd_assert(type == 'Objc');
                      psd_get_layer_pattern_overlay2(context, &data->pattern_overlay);
                      data->fill[psd_layer_effects_type_pattern_overlay] = psd_true;
                      data->valid[psd_layer_effects_type_pattern_overlay] = psd_true;
                      data->effects_count ++;
                  }
                  else
                  {
                      psd_assert(0);
                      psd_stream_get_object_null(type, context);
                  }
                  break;
                  
                  // scale, do not used
              case 'Scl ':
                  // Unit psd_float
                  psd_assert(type == 'UntF');
                  
                  // percent
                  key = psd_stream_get_int(context);
                  psd_assert(key == '#Prc');
                  // Actual value (double)
                  psd_stream_get_double(context);
                  
                  number_items --;
                  length = psd_stream_get_int(context);
                  if(length == 0)
                      psd_stream_get_int(context);
                  else
                      psd_stream_get_null(context, length);
                  // Type: OSType key
                  type = psd_stream_get_int(context);
                  psd_assert(type == 'bool');
                  // Boolean value
                  data->visible = psd_stream_get_bool(context);
                  break;
                  
                  // drop shadow
              case 'DrSh':
                  // Descriptor
                  psd_assert(type == 'Objc');
                  psd_get_layer_drop_shadow2(context, &data->drop_shadow);
                  data->fill[psd_layer_effects_type_drop_shadow] = psd_true;
                  data->valid[psd_layer_effects_type_drop_shadow] = psd_true;
                  data->effects_count ++;
                  break;
                  
                  // inner shadow
              case 'IrSh':
                  // Descriptor
                  psd_assert(type == 'Objc');
                  psd_get_layer_inner_shadow2(context, &data->inner_shadow);
                  data->fill[psd_layer_effects_type_inner_shadow] = psd_true;
                  data->valid[psd_layer_effects_type_inner_shadow] = psd_true;
                  data->effects_count ++;
                  break;
                  
                  // outer glow
              case 'OrGl':
                  // Descriptor
                  psd_assert(type == 'Objc');
                  psd_get_layer_outer_glow2(context, &data->outer_glow);
                  data->fill[psd_layer_effects_type_outer_glow] = psd_true;
                  data->valid[psd_layer_effects_type_outer_glow] = psd_true;
                  data->effects_count ++;
                  break;
                  
                  // inner glow
              case 'IrGl':
                  // Descriptor
                  psd_assert(type == 'Objc');
                  psd_get_layer_inner_glow2(context, &data->inner_glow);
                  data->fill[psd_layer_effects_type_inner_glow] = psd_true;
                  data->valid[psd_layer_effects_type_inner_glow] = psd_true;
                  data->effects_count ++;
                  break;
                  
                  // bevel and emboss
              case 'ebbl':
                  // Descriptor
                  psd_assert(type == 'Objc');
                  psd_get_layer_bevel_emboss2(context, &data->bevel_emboss);
                  data->fill[psd_layer_effects_type_bevel_emboss] = psd_true;
                  data->valid[psd_layer_effects_type_bevel_emboss] = psd_true;
                  data->effects_count ++;
                  break;
                  
                  // satin
              case 'ChFX':
                  // Descriptor
                  psd_assert(type == 'Objc');
                  psd_get_layer_satin2(context, &data->satin);
                  data->fill[psd_layer_effects_type_satin] = psd_true;
                  data->valid[psd_layer_effects_type_satin] = psd_true;
                  data->effects_count ++;
                  break;
                  
                  // color overlay
              case 'SoFi':
                  // Descriptor
                  psd_assert(type == 'Objc');
                  psd_get_layer_color_overlay2(context, &data->color_overlay);
                  data->fill[psd_layer_effects_type_color_overlay] = psd_true;
                  data->valid[psd_layer_effects_type_color_overlay] = psd_true;
                  data->effects_count ++;
                  break;
                  
                  // gradient overlay
              case 'GrFl':
                  // Descriptor
                  psd_assert(type == 'Objc');
                  psd_get_layer_gradient_overlay2(context, &data->gradient_overlay);
                  data->fill[psd_layer_effects_type_gradient_overlay] = psd_true;
                  data->valid[psd_layer_effects_type_gradient_overlay] = psd_true;
                  data->effects_count ++;
                  break;
                  
                  // stroke
              case 'FrFX':
                  // Descriptor
                  psd_assert(type == 'Objc');
                  psd_get_layer_stroke2(context, &data->stroke);
                  data->fill[psd_layer_effects_type_stroke] = psd_true;
                  data->valid[psd_layer_effects_type_stroke] = psd_true;
                  data->effects_count ++;
                  break;
                  
              default:
                  psd_assert(0);
                  psd_stream_get_object_null(type, context);
                  break;
          }
      }
      
      return psd_status_done;
  }
  
  psd_status psd_layer_effects_update(psd_layer_record * layer, psd_layer_effects_type type)
  {
      psd_layer_effects * data = NULL;
      psd_int i;
      
      if(layer == NULL)
          return psd_status_invalid_layer;
      if(type >= psd_layer_effects_type_count)
          return psd_status_invalid_layer_effects;
      
      for(i = 0; i < layer->layer_info_count; i ++)
      {
          if(layer->layer_info_type[i] == psd_layer_info_type_effects)
          {
              data = (psd_layer_effects *)layer->layer_info_data[i];
              break;
          }
      }
      if(data == NULL)
          return psd_status_invalid_layer_effects;
      
      data->valid[type] = psd_true;
      
      return psd_status_done;
  }
  
  
  #ifdef PSD_SUPPORT_EFFECTS_BLEND
  
  static void psd_layer_blend_effects_image(psd_context * context, psd_layer_record * layer,
                                            psd_rect * dst_rect, psd_layer_effects * data, psd_int index)
  {
      psd_rect layer_rect, mask_rect;
      psd_layer_record effects_layer;
      
      if(data->image_data[index] == NULL || data->opacity[index] == 0)
          return;
      
      memcpy(&effects_layer, layer, sizeof(psd_layer_record));
      effects_layer.left = data->left[index] + layer->left;
      effects_layer.top = data->top[index] + layer->top;
      effects_layer.right = data->right[index] + layer->left;
      effects_layer.bottom = data->bottom[index] + layer->top;
      effects_layer.width = data->width[index];
      effects_layer.height = data->height[index];
      effects_layer.fill_opacity = data->opacity[index];
      effects_layer.blend_mode = data->blend_mode[index];
      effects_layer.image_data = data->image_data[index];
      effects_layer.layer_mask_info.disabled = psd_true;
      
      psd_make_rect(&layer_rect, effects_layer.left, effects_layer.top, effects_layer.right, effects_layer.bottom);
      if(psd_incept_rect(dst_rect, &layer_rect, &layer_rect) == psd_true)
      {
          if(effects_layer.layer_mask_info.disabled == psd_false && effects_layer.layer_mask_info.mask_data != NULL && effects_layer.layer_mask_info.default_color == 0)
          {
              psd_make_rect(&mask_rect, effects_layer.layer_mask_info.left, effects_layer.layer_mask_info.top,
                            effects_layer.layer_mask_info.right, effects_layer.layer_mask_info.bottom);
              if(psd_incept_rect(&mask_rect, &layer_rect, &layer_rect) == psd_false)
                  return;
          }
          
          if(psd_layer_check_restricted(context, &effects_layer) == psd_true)
          {
              if(effects_layer.blend_mode != psd_blend_mode_normal ||
                 (effects_layer.group_layer != NULL && effects_layer.group_layer->divider_blend_mode != psd_blend_mode_pass_through))
                  psd_layer_blend_restricted(context, &effects_layer, &layer_rect);
              else
                  psd_layer_blend_normal_restricted(context, &effects_layer, &layer_rect);
          }
          else
          {
              if(effects_layer.blend_mode != psd_blend_mode_normal ||
                 (effects_layer.group_layer != NULL && effects_layer.group_layer->divider_blend_mode != psd_blend_mode_pass_through))
                  psd_layer_blend(context, &effects_layer, &layer_rect);
              else
                  psd_layer_blend_normal(context, &effects_layer, &layer_rect);
          }
      }
  }
  
  psd_bool psd_layer_effects_blend_background(psd_context * context, psd_layer_record * layer, psd_rect * dst_rect)
  {
      psd_layer_effects * data = NULL;
      psd_int i;
      
      if(layer->image_data == NULL || layer->width <= 0 || layer->height <= 0)
          return psd_false;
      
      for(i = 0; i < layer->layer_info_count; i ++)
      {
          if(layer->layer_info_type[i] == psd_layer_info_type_effects2)
          {
              data = (psd_layer_effects *)layer->layer_info_data[i];
              break;
          }
      }
      if(data == NULL)
      {
          for(i = 0; i < layer->layer_info_count; i ++)
          {
              if(layer->layer_info_type[i] == psd_layer_info_type_effects)
              {
                  data = (psd_layer_effects *)layer->layer_info_data[i];
                  break;
              }
          }
      }
      if(data == NULL)
          return psd_false;
      
      if(data->effects_count == 0 || data->visible == psd_false)
          return psd_false;
      
      for(i = psd_layer_effects_type_count - 1; i >= 0; i --)
      {
          if(data->fill[i] == psd_false)
              continue;
          
          switch(i)
          {
              case psd_layer_effects_type_drop_shadow:
                  if(data->drop_shadow.effect_enable == psd_false)
                      continue;
                  if(data->valid[i] == psd_true)
                      psd_layer_effects_blend_drop_shadow(context, layer, data);
                  break;
              case psd_layer_effects_type_bevel_emboss:
                  if(data->bevel_emboss.effect_enable == psd_false)
                      continue;
                  if(data->valid[i] == psd_true)
                      NULL;
                  break;
              default:
                  continue;
          }
          
          if(i == psd_layer_effects_type_bevel_emboss)
          {
              psd_layer_blend_effects_image(context, layer, dst_rect, data,
                                            psd_layer_effects_bevel_emboss_outer_shadow);
              psd_layer_blend_effects_image(context, layer, dst_rect, data,
                                            psd_layer_effects_bevel_emboss_inner_shadow);
          }
          else
          {
              psd_layer_blend_effects_image(context, layer, dst_rect, data, i);
          }
      }
      
      return psd_true;
  }
  
  psd_bool psd_layer_effects_blend_foreground(psd_context * context, psd_layer_record * layer, psd_rect * dst_rect)
  {
      psd_layer_effects * data = NULL;
      psd_int i;
      
      if(layer->image_data == NULL || layer->width <= 0 || layer->height <= 0)
          return psd_false;
      
      for(i = 0; i < layer->layer_info_count; i ++)
      {
          if(layer->layer_info_type[i] == psd_layer_info_type_effects2)
          {
              data = (psd_layer_effects *)layer->layer_info_data[i];
              break;
          }
      }
      if(data == NULL)
      {
          for(i = 0; i < layer->layer_info_count; i ++)
          {
              if(layer->layer_info_type[i] == psd_layer_info_type_effects)
              {
                  data = (psd_layer_effects *)layer->layer_info_data[i];
                  break;
              }
          }
      }
      if(data == NULL)
          return psd_false;
      
      if(data->effects_count == 0 || data->visible == psd_false)
          return psd_false;
      
      for(i = psd_layer_effects_type_count - 1; i >= 0; i --)
      {
          if(data->fill[i] == psd_false)
              continue;
          
          switch(i)
          {
              case psd_layer_effects_type_inner_shadow:
                  if(data->inner_shadow.effect_enable == psd_false)
                      continue;
                  if(data->valid[i] == psd_true)
                      psd_layer_effects_blend_inner_shadow(context, layer, data);
                  break;
              case psd_layer_effects_type_outer_glow:
                  if(data->outer_glow.effect_enable == psd_false)
                      continue;
                  if(data->valid[i] == psd_true)
                      psd_layer_effects_blend_outer_glow(context, layer, data);
                  break;
              case psd_layer_effects_type_inner_glow:
                  if(data->inner_glow.effect_enable == psd_false)
                      continue;
                  if(data->valid[i] == psd_true)
                      psd_layer_effects_blend_inner_glow(context, layer, data);
                  break;
              case psd_layer_effects_type_bevel_emboss:
                  if(data->bevel_emboss.effect_enable == psd_false)
                      continue;
                  // do nothing
                  break;
              case psd_layer_effects_type_satin:
                  if(data->satin.effect_enable == psd_false)
                      continue;
                  if(data->valid[i] == psd_true)
                      psd_layer_effects_blend_satin(context, layer, data);
                  break;
              case psd_layer_effects_type_color_overlay:
                  if(data->color_overlay.effect_enable == psd_false)
                      continue;
                  if(data->valid[i] == psd_true)
                      psd_layer_effects_blend_color_overlay(context, layer, data);
                  break;
              case psd_layer_effects_type_gradient_overlay:
                  if(data->gradient_overlay.effect_enable == psd_false)
                      continue;
                  if(data->valid[i] == psd_true)
                      psd_layer_effects_blend_gradient_overlay(context, layer, data);
                  break;
              case psd_layer_effects_type_pattern_overlay:
                  if(data->pattern_overlay.effect_enable == psd_false)
                      continue;
                  if(data->valid[i] == psd_true)
                      psd_layer_effects_blend_pattern_overlay(context, layer, data);
                  break;
              case psd_layer_effects_type_stroke:
                  if(data->stroke.effect_enable == psd_false)
                      continue;
                  if(data->valid[i] == psd_true)
                      psd_layer_effects_blend_stroke(context, layer, data);
                  break;
              default:
                  continue;
          }
          
          if(data->image_data[i] == NULL)
              continue;
          
          if(i == psd_layer_effects_type_bevel_emboss)
          {
              psd_layer_blend_effects_image(context, layer, dst_rect, data,
                                            psd_layer_effects_bevel_emboss_outer_light);
              psd_layer_blend_effects_image(context, layer, dst_rect, data,
                                            psd_layer_effects_bevel_emboss_inner_light);
              psd_layer_blend_effects_image(context, layer, dst_rect, data,
                                            psd_layer_effects_bevel_emboss_texture);
          }
          else
          {
              psd_layer_blend_effects_image(context, layer, dst_rect, data, i);
          }
      }
      
      return psd_true;
  }
  
  void psd_effects_add_noise(psd_bitmap * bitmap, psd_int noise, psd_int left, psd_int top, psd_context * context)
  {
      psd_int i, j, x, y, width, height;
      psd_int src_alpha, dst_alpha, next_alpha;
      psd_argb_color * src_data, * dst_data;
      psd_uchar * rand_data;
      psd_bitmap noise_bmp;
      
      width = bitmap->width;
      height = bitmap->height;
      psd_get_bitmap(&noise_bmp, width, height, context);
      psd_fill_bitmap(&noise_bmp, psd_color_clear);
      
      for(i = PSD_MAX(-top, 0); i < height; i ++)
      {
          if(i + top >= context->height)
              break;
          
          src_data = bitmap->image_data + i * bitmap->width + PSD_MAX(-left, 0);
          rand_data = context->rand_data + (i + top) * context->width + left;
          for(j = PSD_MAX(-left, 0); j < width; j ++, src_data ++, rand_data ++)
          {
              if(j + left >= context->width)
                  break;
              
              x = j + (*rand_data >> 4) - 8;
              y = i + (*rand_data & 0x0F) - 8;
              x = (x + j) >> 1;
              y = (y + i) >> 1;
              if(x < 0 || x >= width || y < 0 || y >= height)
                  continue;
              
              src_alpha = PSD_GET_ALPHA_COMPONENT(*src_data);
              dst_data = noise_bmp.image_data + y * width + x;
              dst_alpha = PSD_GET_ALPHA_COMPONENT(*dst_data);
              if(dst_alpha + src_alpha <= 255)
              {
                  dst_alpha = dst_alpha + src_alpha;
                  *dst_data = (*src_data & 0x00FFFFFF) | (dst_alpha << 24);
              }
              else
              {
                  *dst_data = (*src_data & 0x00FFFFFF) | 0xFF000000;
                  if(x + 1 < width)
                  {
                      next_alpha = dst_alpha + src_alpha - 255;
                      *(dst_data + 1) = (*src_data & 0x00FFFFFF) | (next_alpha << 24);
                  }
              }
          }
      }
      
      noise = noise * 256 / 100;
      if(noise == 256)
      {
          psd_copy_bitmap(bitmap, &noise_bmp);
      }
      else
      {
          src_data = noise_bmp.image_data;
          dst_data = bitmap->image_data;
          for(i = width * height; i --; src_data ++, dst_data ++)
          {
              src_alpha = PSD_GET_ALPHA_COMPONENT(*src_data);
              dst_alpha = PSD_GET_ALPHA_COMPONENT(*dst_data);
              dst_alpha = ((dst_alpha << 8) + (src_alpha - dst_alpha) * noise) >> 8;
              *dst_data = (*dst_data & 0x00FFFFFF) | (dst_alpha << 24);
          }
      }
  }
  
  void psd_effects_apply_gradient(psd_bitmap * bitmap, psd_argb_color * gradient_table, psd_bool edge_hidden, 
                                  psd_int jitter, psd_int left, psd_int top, psd_context * context)
  {
      psd_int i, j, alpha, gradient_index;
      psd_argb_color * dst_data;
      psd_uchar * rand_data;
      
      if(jitter > 0)
      {
          jitter = jitter * 256 / 100;
          for(i = PSD_MAX(-top, 0); i < bitmap->height; i ++)
          {
              if(i + top >= context->height)
                  break;
              
              dst_data = bitmap->image_data + i * bitmap->width + PSD_MAX(-left, 0);
              rand_data = context->rand_data + (i + top) * context->width + left;
              for(j = PSD_MAX(-left, 0); j < bitmap->width; j ++, dst_data ++, rand_data ++)
              {
                  if(j + left >= context->width)
                      break;
                  alpha = PSD_GET_ALPHA_COMPONENT(*dst_data);
                  gradient_index = 255 - alpha;
                  gradient_index += jitter * *rand_data >> 8;
                  gradient_index &= 0xFF;
                  
                  if(edge_hidden == psd_true && alpha < 24)
                  {
                      if(PSD_GET_ALPHA_COMPONENT(gradient_table[gradient_index]) != 255)
                      {
                          *dst_data = gradient_table[gradient_index];
                      }
                      else
                      {
                          *dst_data = (gradient_table[gradient_index] & 0x00FFFFFF) | 
                          (alpha * 10 * PSD_GET_ALPHA_COMPONENT(gradient_table[gradient_index]) >> 8 << 24);
                      }
                  }
                  else
                  {
                      *dst_data = gradient_table[gradient_index];
                  }
              }
          }
      }
      else
      {
          dst_data = bitmap->image_data;
          for(i = bitmap->width * bitmap->height; i --; )
          {
              alpha = PSD_GET_ALPHA_COMPONENT(*dst_data);
              if(edge_hidden == psd_true && alpha < 24)
              {
                  if(PSD_GET_ALPHA_COMPONENT(gradient_table[255 - alpha]) != 255)
                  {
                      *dst_data = gradient_table[255 - alpha];
                  }
                  else
                  {
                      *dst_data = (gradient_table[255 - alpha] & 0x00FFFFFF) | 
                      (alpha * 10 * PSD_GET_ALPHA_COMPONENT(gradient_table[255 - alpha]) >> 8 << 24);
                  }
              }
              else
              {
                  *dst_data = gradient_table[255 - alpha];
              }
              dst_data ++;
          }
      }
  }
  
  #endif // ifdef PSD_SUPPORT_EFFECTS_BLEND
  
  
  static void psd_gradient_color_free(psd_gradient_color * gradient_color)
  {
      psd_freeif(gradient_color->name);
      psd_freeif(gradient_color->color_stop);
      psd_freeif(gradient_color->transparency_stop);
  }
  
  static void psd_pattern_info_free(psd_pattern_info * pattern_info)
  {
      psd_freeif(pattern_info->name);
  }
  
  void psd_layer_effects_free(psd_ptr layer_info)
  {
      psd_layer_effects * data;
      psd_int i;
      
      data = (psd_layer_effects *)layer_info;
      if(data == NULL)
          return;
      
      for(i = 0; i < psd_layer_effects_image_count; i ++)
      {
          psd_freeif(data->image_data[i]);
          data->image_data[i] = NULL;
      }
      
      psd_pattern_info_free(&data->bevel_emboss.texture_pattern_info);
      psd_gradient_color_free(&data->gradient_overlay.gradient_color);
      psd_pattern_info_free(&data->pattern_overlay.pattern_info);
      psd_gradient_color_free(&data->stroke.gradient_color);
      psd_pattern_info_free(&data->stroke.pattern_info);
      
      psd_free(data);
  }
  
  