harfbuzz/src/hb-shape-plan.cc

580 lines
16 KiB
C++

/*
* Copyright © 2012 Google, Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Google Author(s): Behdad Esfahbod
*/
#include "hb.hh"
#include "hb-shape-plan.hh"
#include "hb-shaper.hh"
#include "hb-font.hh"
#include "hb-buffer.hh"
/**
* SECTION:hb-shape-plan
* @title: hb-shape-plan
* @short_description: Object representing a shaping plan
* @include: hb.h
*
* Shape plans are an internal mechanism. Each plan contains state
* describing how HarfBuzz will shape a particular text segment, based on
* the combination of segment properties and the capabilities in the
* font face in use.
*
* Shape plans are not used for shaping directly, but can be queried to
* access certain information about how shaping will perform, given a set
* of specific input parameters (script, language, direction, features,
* etc.).
*
* Most client programs will not need to deal with shape plans directly.
**/
/*
* hb_shape_plan_key_t
*/
bool
hb_shape_plan_key_t::init (bool copy,
hb_face_t *face,
const hb_segment_properties_t *props,
const hb_feature_t *user_features,
unsigned int num_user_features,
const int *coords,
unsigned int num_coords,
const char * const *shaper_list)
{
hb_feature_t *features = nullptr;
if (copy && num_user_features && !(features = (hb_feature_t *) hb_calloc (num_user_features, sizeof (hb_feature_t))))
goto bail;
this->props = *props;
this->num_user_features = num_user_features;
this->user_features = copy ? features : user_features;
if (copy && num_user_features)
{
memcpy (features, user_features, num_user_features * sizeof (hb_feature_t));
/* Make start/end uniform to easier catch bugs. */
for (unsigned int i = 0; i < num_user_features; i++)
{
if (features[0].start != HB_FEATURE_GLOBAL_START)
features[0].start = 1;
if (features[0].end != HB_FEATURE_GLOBAL_END)
features[0].end = 2;
}
}
this->shaper_func = nullptr;
this->shaper_name = nullptr;
#ifndef HB_NO_OT_SHAPE
this->ot.init (face, coords, num_coords);
#endif
/*
* Choose shaper.
*/
#define HB_SHAPER_PLAN(shaper) \
HB_STMT_START { \
if (face->data.shaper) \
{ \
this->shaper_func = _hb_##shaper##_shape; \
this->shaper_name = #shaper; \
return true; \
} \
} HB_STMT_END
if (unlikely (shaper_list))
{
for (; *shaper_list; shaper_list++)
if (false)
;
#define HB_SHAPER_IMPLEMENT(shaper) \
else if (0 == strcmp (*shaper_list, #shaper)) \
HB_SHAPER_PLAN (shaper);
#include "hb-shaper-list.hh"
#undef HB_SHAPER_IMPLEMENT
}
else
{
const hb_shaper_entry_t *shapers = _hb_shapers_get ();
for (unsigned int i = 0; i < HB_SHAPERS_COUNT; i++)
if (false)
;
#define HB_SHAPER_IMPLEMENT(shaper) \
else if (shapers[i].func == _hb_##shaper##_shape) \
HB_SHAPER_PLAN (shaper);
#include "hb-shaper-list.hh"
#undef HB_SHAPER_IMPLEMENT
}
#undef HB_SHAPER_PLAN
bail:
::hb_free (features);
return false;
}
bool
hb_shape_plan_key_t::user_features_match (const hb_shape_plan_key_t *other)
{
if (this->num_user_features != other->num_user_features)
return false;
for (unsigned int i = 0; i < num_user_features; i++)
{
if (this->user_features[i].tag != other->user_features[i].tag ||
this->user_features[i].value != other->user_features[i].value ||
(this->user_features[i].start == HB_FEATURE_GLOBAL_START &&
this->user_features[i].end == HB_FEATURE_GLOBAL_END) !=
(other->user_features[i].start == HB_FEATURE_GLOBAL_START &&
other->user_features[i].end == HB_FEATURE_GLOBAL_END))
return false;
}
return true;
}
bool
hb_shape_plan_key_t::equal (const hb_shape_plan_key_t *other)
{
return hb_segment_properties_equal (&this->props, &other->props) &&
this->user_features_match (other) &&
#ifndef HB_NO_OT_SHAPE
this->ot.equal (&other->ot) &&
#endif
this->shaper_func == other->shaper_func;
}
/*
* hb_shape_plan_t
*/
/**
* hb_shape_plan_create: (Xconstructor)
* @face: #hb_face_t to use
* @props: The #hb_segment_properties_t of the segment
* @user_features: (array length=num_user_features): The list of user-selected features
* @num_user_features: The number of user-selected features
* @shaper_list: (array zero-terminated=1): List of shapers to try
*
* Constructs a shaping plan for a combination of @face, @user_features, @props,
* and @shaper_list.
*
* Return value: (transfer full): The shaping plan
*
* Since: 0.9.7
**/
hb_shape_plan_t *
hb_shape_plan_create (hb_face_t *face,
const hb_segment_properties_t *props,
const hb_feature_t *user_features,
unsigned int num_user_features,
const char * const *shaper_list)
{
return hb_shape_plan_create2 (face, props,
user_features, num_user_features,
nullptr, 0,
shaper_list);
}
/**
* hb_shape_plan_create2: (Xconstructor)
* @face: #hb_face_t to use
* @props: The #hb_segment_properties_t of the segment
* @user_features: (array length=num_user_features): The list of user-selected features
* @num_user_features: The number of user-selected features
* @coords: (array length=num_coords): The list of variation-space coordinates
* @num_coords: The number of variation-space coordinates
* @shaper_list: (array zero-terminated=1): List of shapers to try
*
* The variable-font version of #hb_shape_plan_create.
* Constructs a shaping plan for a combination of @face, @user_features, @props,
* and @shaper_list, plus the variation-space coordinates @coords.
*
* Return value: (transfer full): The shaping plan
*
* Since: 1.4.0
**/
hb_shape_plan_t *
hb_shape_plan_create2 (hb_face_t *face,
const hb_segment_properties_t *props,
const hb_feature_t *user_features,
unsigned int num_user_features,
const int *coords,
unsigned int num_coords,
const char * const *shaper_list)
{
DEBUG_MSG_FUNC (SHAPE_PLAN, nullptr,
"face=%p num_features=%d num_coords=%d shaper_list=%p",
face,
num_user_features,
num_coords,
shaper_list);
assert (props->direction != HB_DIRECTION_INVALID);
hb_shape_plan_t *shape_plan;
if (unlikely (!props))
goto bail;
if (!(shape_plan = hb_object_create<hb_shape_plan_t> ()))
goto bail;
if (unlikely (!face))
face = hb_face_get_empty ();
hb_face_make_immutable (face);
shape_plan->face_unsafe = face;
if (unlikely (!shape_plan->key.init (true,
face,
props,
user_features,
num_user_features,
coords,
num_coords,
shaper_list)))
goto bail2;
#ifndef HB_NO_OT_SHAPE
if (unlikely (!shape_plan->ot.init0 (face, &shape_plan->key)))
goto bail3;
#endif
return shape_plan;
#ifndef HB_NO_OT_SHAPE
bail3:
#endif
shape_plan->key.fini ();
bail2:
hb_free (shape_plan);
bail:
return hb_shape_plan_get_empty ();
}
/**
* hb_shape_plan_get_empty:
*
* Fetches the singleton empty shaping plan.
*
* Return value: (transfer full): The empty shaping plan
*
* Since: 0.9.7
**/
hb_shape_plan_t *
hb_shape_plan_get_empty ()
{
return const_cast<hb_shape_plan_t *> (&Null (hb_shape_plan_t));
}
/**
* hb_shape_plan_reference: (skip)
* @shape_plan: A shaping plan
*
* Increases the reference count on the given shaping plan.
*
* Return value: (transfer full): @shape_plan
*
* Since: 0.9.7
**/
hb_shape_plan_t *
hb_shape_plan_reference (hb_shape_plan_t *shape_plan)
{
return hb_object_reference (shape_plan);
}
/**
* hb_shape_plan_destroy: (skip)
* @shape_plan: A shaping plan
*
* Decreases the reference count on the given shaping plan. When the
* reference count reaches zero, the shaping plan is destroyed,
* freeing all memory.
*
* Since: 0.9.7
**/
void
hb_shape_plan_destroy (hb_shape_plan_t *shape_plan)
{
if (!hb_object_destroy (shape_plan)) return;
#ifndef HB_NO_OT_SHAPE
shape_plan->ot.fini ();
#endif
shape_plan->key.fini ();
hb_free (shape_plan);
}
/**
* hb_shape_plan_set_user_data: (skip)
* @shape_plan: A shaping plan
* @key: The user-data key to set
* @data: A pointer to the user data
* @destroy: (nullable): A callback to call when @data is not needed anymore
* @replace: Whether to replace an existing data with the same key
*
* Attaches a user-data key/data pair to the given shaping plan.
*
* Return value: %true if success, %false otherwise.
*
* Since: 0.9.7
**/
hb_bool_t
hb_shape_plan_set_user_data (hb_shape_plan_t *shape_plan,
hb_user_data_key_t *key,
void * data,
hb_destroy_func_t destroy,
hb_bool_t replace)
{
return hb_object_set_user_data (shape_plan, key, data, destroy, replace);
}
/**
* hb_shape_plan_get_user_data: (skip)
* @shape_plan: A shaping plan
* @key: The user-data key to query
*
* Fetches the user data associated with the specified key,
* attached to the specified shaping plan.
*
* Return value: (transfer none): A pointer to the user data
*
* Since: 0.9.7
**/
void *
hb_shape_plan_get_user_data (hb_shape_plan_t *shape_plan,
hb_user_data_key_t *key)
{
return hb_object_get_user_data (shape_plan, key);
}
/**
* hb_shape_plan_get_shaper:
* @shape_plan: A shaping plan
*
* Fetches the shaper from a given shaping plan.
*
* Return value: (transfer none): The shaper
*
* Since: 0.9.7
**/
const char *
hb_shape_plan_get_shaper (hb_shape_plan_t *shape_plan)
{
return shape_plan->key.shaper_name;
}
static bool
_hb_shape_plan_execute_internal (hb_shape_plan_t *shape_plan,
hb_font_t *font,
hb_buffer_t *buffer,
const hb_feature_t *features,
unsigned int num_features)
{
DEBUG_MSG_FUNC (SHAPE_PLAN, shape_plan,
"num_features=%d shaper_func=%p, shaper_name=%s",
num_features,
shape_plan->key.shaper_func,
shape_plan->key.shaper_name);
if (unlikely (!buffer->len))
return true;
assert (!hb_object_is_immutable (buffer));
buffer->assert_unicode ();
if (unlikely (!hb_object_is_valid (shape_plan)))
return false;
assert (shape_plan->face_unsafe == font->face);
assert (hb_segment_properties_equal (&shape_plan->key.props, &buffer->props));
#define HB_SHAPER_EXECUTE(shaper) \
HB_STMT_START { \
return font->data.shaper && \
_hb_##shaper##_shape (shape_plan, font, buffer, features, num_features); \
} HB_STMT_END
if (false)
;
#define HB_SHAPER_IMPLEMENT(shaper) \
else if (shape_plan->key.shaper_func == _hb_##shaper##_shape) \
HB_SHAPER_EXECUTE (shaper);
#include "hb-shaper-list.hh"
#undef HB_SHAPER_IMPLEMENT
#undef HB_SHAPER_EXECUTE
return false;
}
/**
* hb_shape_plan_execute:
* @shape_plan: A shaping plan
* @font: The #hb_font_t to use
* @buffer: The #hb_buffer_t to work upon
* @features: (array length=num_features): Features to enable
* @num_features: The number of features to enable
*
* Executes the given shaping plan on the specified buffer, using
* the given @font and @features.
*
* Return value: %true if success, %false otherwise.
*
* Since: 0.9.7
**/
hb_bool_t
hb_shape_plan_execute (hb_shape_plan_t *shape_plan,
hb_font_t *font,
hb_buffer_t *buffer,
const hb_feature_t *features,
unsigned int num_features)
{
bool ret = _hb_shape_plan_execute_internal (shape_plan, font, buffer,
features, num_features);
if (ret && buffer->content_type == HB_BUFFER_CONTENT_TYPE_UNICODE)
buffer->content_type = HB_BUFFER_CONTENT_TYPE_GLYPHS;
return ret;
}
/*
* Caching
*/
/**
* hb_shape_plan_create_cached:
* @face: #hb_face_t to use
* @props: The #hb_segment_properties_t of the segment
* @user_features: (array length=num_user_features): The list of user-selected features
* @num_user_features: The number of user-selected features
* @shaper_list: (array zero-terminated=1): List of shapers to try
*
* Creates a cached shaping plan suitable for reuse, for a combination
* of @face, @user_features, @props, and @shaper_list.
*
* Return value: (transfer full): The shaping plan
*
* Since: 0.9.7
**/
hb_shape_plan_t *
hb_shape_plan_create_cached (hb_face_t *face,
const hb_segment_properties_t *props,
const hb_feature_t *user_features,
unsigned int num_user_features,
const char * const *shaper_list)
{
return hb_shape_plan_create_cached2 (face, props,
user_features, num_user_features,
nullptr, 0,
shaper_list);
}
/**
* hb_shape_plan_create_cached2:
* @face: #hb_face_t to use
* @props: The #hb_segment_properties_t of the segment
* @user_features: (array length=num_user_features): The list of user-selected features
* @num_user_features: The number of user-selected features
* @coords: (array length=num_coords): The list of variation-space coordinates
* @num_coords: The number of variation-space coordinates
* @shaper_list: (array zero-terminated=1): List of shapers to try
*
* The variable-font version of #hb_shape_plan_create_cached.
* Creates a cached shaping plan suitable for reuse, for a combination
* of @face, @user_features, @props, and @shaper_list, plus the
* variation-space coordinates @coords.
*
* Return value: (transfer full): The shaping plan
*
* Since: 1.4.0
**/
hb_shape_plan_t *
hb_shape_plan_create_cached2 (hb_face_t *face,
const hb_segment_properties_t *props,
const hb_feature_t *user_features,
unsigned int num_user_features,
const int *coords,
unsigned int num_coords,
const char * const *shaper_list)
{
DEBUG_MSG_FUNC (SHAPE_PLAN, nullptr,
"face=%p num_features=%d shaper_list=%p",
face,
num_user_features,
shaper_list);
retry:
hb_face_t::plan_node_t *cached_plan_nodes = face->shape_plans;
bool dont_cache = !hb_object_is_valid (face);
if (likely (!dont_cache))
{
hb_shape_plan_key_t key;
if (!key.init (false,
face,
props,
user_features,
num_user_features,
coords,
num_coords,
shaper_list))
return hb_shape_plan_get_empty ();
for (hb_face_t::plan_node_t *node = cached_plan_nodes; node; node = node->next)
if (node->shape_plan->key.equal (&key))
{
DEBUG_MSG_FUNC (SHAPE_PLAN, node->shape_plan, "fulfilled from cache");
return hb_shape_plan_reference (node->shape_plan);
}
}
hb_shape_plan_t *shape_plan = hb_shape_plan_create2 (face, props,
user_features, num_user_features,
coords, num_coords,
shaper_list);
if (unlikely (dont_cache))
return shape_plan;
hb_face_t::plan_node_t *node = (hb_face_t::plan_node_t *) hb_calloc (1, sizeof (hb_face_t::plan_node_t));
if (unlikely (!node))
return shape_plan;
node->shape_plan = shape_plan;
node->next = cached_plan_nodes;
if (unlikely (!face->shape_plans.cmpexch (cached_plan_nodes, node)))
{
hb_shape_plan_destroy (shape_plan);
hb_free (node);
goto retry;
}
DEBUG_MSG_FUNC (SHAPE_PLAN, shape_plan, "inserted into cache");
return hb_shape_plan_reference (shape_plan);
}