harfbuzz/src/hb-draw.cc

459 lines
12 KiB
C++

/*
* Copyright © 2019-2020 Ebrahim Byagowi
*
* 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.
*/
#include "hb.hh"
#ifndef HB_NO_DRAW
#include "hb-draw.hh"
/**
* SECTION:hb-draw
* @title: hb-draw
* @short_description: Glyph drawing
* @include: hb.h
*
* Functions for drawing (extracting) glyph shapes.
*
* The #hb_draw_funcs_t struct can be used with hb_font_draw_glyph().
**/
static void
hb_draw_move_to_nil (hb_draw_funcs_t *dfuncs HB_UNUSED, void *draw_data HB_UNUSED,
hb_draw_state_t *st HB_UNUSED,
float to_x HB_UNUSED, float to_y HB_UNUSED,
void *user_data HB_UNUSED) {}
static void
hb_draw_line_to_nil (hb_draw_funcs_t *dfuncs HB_UNUSED, void *draw_data HB_UNUSED,
hb_draw_state_t *st HB_UNUSED,
float to_x HB_UNUSED, float to_y HB_UNUSED,
void *user_data HB_UNUSED) {}
static void
hb_draw_quadratic_to_nil (hb_draw_funcs_t *dfuncs, void *draw_data,
hb_draw_state_t *st,
float control_x, float control_y,
float to_x, float to_y,
void *user_data HB_UNUSED)
{
#define HB_ONE_THIRD 0.33333333f
dfuncs->emit_cubic_to (draw_data, *st,
(st->current_x + 2.f * control_x) * HB_ONE_THIRD,
(st->current_y + 2.f * control_y) * HB_ONE_THIRD,
(to_x + 2.f * control_x) * HB_ONE_THIRD,
(to_y + 2.f * control_y) * HB_ONE_THIRD,
to_x, to_y);
#undef HB_ONE_THIRD
}
static void
hb_draw_cubic_to_nil (hb_draw_funcs_t *dfuncs HB_UNUSED, void *draw_data HB_UNUSED,
hb_draw_state_t *st HB_UNUSED,
float control1_x HB_UNUSED, float control1_y HB_UNUSED,
float control2_x HB_UNUSED, float control2_y HB_UNUSED,
float to_x HB_UNUSED, float to_y HB_UNUSED,
void *user_data HB_UNUSED) {}
static void
hb_draw_close_path_nil (hb_draw_funcs_t *dfuncs HB_UNUSED, void *draw_data HB_UNUSED,
hb_draw_state_t *st HB_UNUSED,
void *user_data HB_UNUSED) {}
static bool
_hb_draw_funcs_set_preamble (hb_draw_funcs_t *dfuncs,
bool func_is_null,
void **user_data,
hb_destroy_func_t *destroy)
{
if (hb_object_is_immutable (dfuncs))
{
if (*destroy)
(*destroy) (*user_data);
return false;
}
if (func_is_null)
{
if (*destroy)
(*destroy) (*user_data);
*destroy = nullptr;
*user_data = nullptr;
}
return true;
}
static bool
_hb_draw_funcs_set_middle (hb_draw_funcs_t *dfuncs,
void *user_data,
hb_destroy_func_t destroy)
{
if (user_data && !dfuncs->user_data)
{
dfuncs->user_data = (decltype (dfuncs->user_data)) hb_calloc (1, sizeof (*dfuncs->user_data));
if (unlikely (!dfuncs->user_data))
goto fail;
}
if (destroy && !dfuncs->destroy)
{
dfuncs->destroy = (decltype (dfuncs->destroy)) hb_calloc (1, sizeof (*dfuncs->destroy));
if (unlikely (!dfuncs->destroy))
goto fail;
}
return true;
fail:
if (destroy)
(destroy) (user_data);
return false;
}
#define HB_DRAW_FUNC_IMPLEMENT(name) \
\
void \
hb_draw_funcs_set_##name##_func (hb_draw_funcs_t *dfuncs, \
hb_draw_##name##_func_t func, \
void *user_data, \
hb_destroy_func_t destroy) \
{ \
if (!_hb_draw_funcs_set_preamble (dfuncs, !func, &user_data, &destroy))\
return; \
\
if (dfuncs->destroy && dfuncs->destroy->name) \
dfuncs->destroy->name (!dfuncs->user_data ? nullptr : dfuncs->user_data->name); \
\
if (!_hb_draw_funcs_set_middle (dfuncs, user_data, destroy)) \
return; \
\
if (func) \
dfuncs->func.name = func; \
else \
dfuncs->func.name = hb_draw_##name##_nil; \
\
if (dfuncs->user_data) \
dfuncs->user_data->name = user_data; \
if (dfuncs->destroy) \
dfuncs->destroy->name = destroy; \
}
HB_DRAW_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_DRAW_FUNC_IMPLEMENT
/**
* hb_draw_funcs_create:
*
* Creates a new draw callbacks object.
*
* Return value: (transfer full):
* A newly allocated #hb_draw_funcs_t with a reference count of 1. The initial
* reference count should be released with hb_draw_funcs_destroy when you are
* done using the #hb_draw_funcs_t. This function never returns `NULL`. If
* memory cannot be allocated, a special singleton #hb_draw_funcs_t object will
* be returned.
*
* Since: 4.0.0
**/
hb_draw_funcs_t *
hb_draw_funcs_create ()
{
hb_draw_funcs_t *dfuncs;
if (unlikely (!(dfuncs = hb_object_create<hb_draw_funcs_t> ())))
return const_cast<hb_draw_funcs_t *> (&Null (hb_draw_funcs_t));
dfuncs->func = Null (hb_draw_funcs_t).func;
return dfuncs;
}
DEFINE_NULL_INSTANCE (hb_draw_funcs_t) =
{
HB_OBJECT_HEADER_STATIC,
{
#define HB_DRAW_FUNC_IMPLEMENT(name) hb_draw_##name##_nil,
HB_DRAW_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_DRAW_FUNC_IMPLEMENT
}
};
/**
* hb_draw_funcs_get_empty:
*
* Fetches the singleton empty draw-functions structure.
*
* Return value: (transfer full): The empty draw-functions structure
*
* Since: REPLACEME
**/
hb_draw_funcs_t *
hb_draw_funcs_get_empty ()
{
return const_cast<hb_draw_funcs_t *> (&Null (hb_draw_funcs_t));
}
/**
* hb_draw_funcs_reference: (skip)
* @dfuncs: draw functions
*
* Increases the reference count on @dfuncs by one.
*
* This prevents @dfuncs from being destroyed until a matching
* call to hb_draw_funcs_destroy() is made.
*
* Return value: (transfer full):
* The referenced #hb_draw_funcs_t.
*
* Since: 4.0.0
**/
hb_draw_funcs_t *
hb_draw_funcs_reference (hb_draw_funcs_t *dfuncs)
{
return hb_object_reference (dfuncs);
}
/**
* hb_draw_funcs_destroy: (skip)
* @dfuncs: draw functions
*
* Deallocate the @dfuncs.
* Decreases the reference count on @dfuncs by one. If the result is zero, then
* @dfuncs and all associated resources are freed. See hb_draw_funcs_reference().
*
* Since: 4.0.0
**/
void
hb_draw_funcs_destroy (hb_draw_funcs_t *dfuncs)
{
if (!hb_object_destroy (dfuncs)) return;
if (dfuncs->destroy)
{
#define HB_DRAW_FUNC_IMPLEMENT(name) \
if (dfuncs->destroy->name) dfuncs->destroy->name (!dfuncs->user_data ? nullptr : dfuncs->user_data->name);
HB_DRAW_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_DRAW_FUNC_IMPLEMENT
}
hb_free (dfuncs->destroy);
hb_free (dfuncs->user_data);
hb_free (dfuncs);
}
/**
* hb_draw_funcs_set_user_data: (skip)
* @dfuncs: The draw-functions structure
* @key: The user-data key
* @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 specified draw-functions structure.
*
* Return value: `true` if success, `false` otherwise
*
* Since: REPLACEME
**/
hb_bool_t
hb_draw_funcs_set_user_data (hb_draw_funcs_t *dfuncs,
hb_user_data_key_t *key,
void * data,
hb_destroy_func_t destroy,
hb_bool_t replace)
{
return hb_object_set_user_data (dfuncs, key, data, destroy, replace);
}
/**
* hb_draw_funcs_get_user_data: (skip)
* @dfuncs: The draw-functions structure
* @key: The user-data key to query
*
* Fetches the user-data associated with the specified key,
* attached to the specified draw-functions structure.
*
* Return value: (transfer none): A pointer to the user data
*
* Since: REPLACEME
**/
void *
hb_draw_funcs_get_user_data (const hb_draw_funcs_t *dfuncs,
hb_user_data_key_t *key)
{
return hb_object_get_user_data (dfuncs, key);
}
/**
* hb_draw_funcs_make_immutable:
* @dfuncs: draw functions
*
* Makes @dfuncs object immutable.
*
* Since: 4.0.0
**/
void
hb_draw_funcs_make_immutable (hb_draw_funcs_t *dfuncs)
{
if (hb_object_is_immutable (dfuncs))
return;
hb_object_make_immutable (dfuncs);
}
/**
* hb_draw_funcs_is_immutable:
* @dfuncs: draw functions
*
* Checks whether @dfuncs is immutable.
*
* Return value: `true` if @dfuncs is immutable, `false` otherwise
*
* Since: 4.0.0
**/
hb_bool_t
hb_draw_funcs_is_immutable (hb_draw_funcs_t *dfuncs)
{
return hb_object_is_immutable (dfuncs);
}
/**
* hb_draw_move_to:
* @dfuncs: draw functions
* @draw_data: associated draw data passed by the caller
* @st: current draw state
* @to_x: X component of target point
* @to_y: Y component of target point
*
* Perform a "move-to" draw operation.
*
* Since: 4.0.0
**/
void
hb_draw_move_to (hb_draw_funcs_t *dfuncs, void *draw_data,
hb_draw_state_t *st,
float to_x, float to_y)
{
dfuncs->move_to (draw_data, *st,
to_x, to_y);
}
/**
* hb_draw_line_to:
* @dfuncs: draw functions
* @draw_data: associated draw data passed by the caller
* @st: current draw state
* @to_x: X component of target point
* @to_y: Y component of target point
*
* Perform a "line-to" draw operation.
*
* Since: 4.0.0
**/
void
hb_draw_line_to (hb_draw_funcs_t *dfuncs, void *draw_data,
hb_draw_state_t *st,
float to_x, float to_y)
{
dfuncs->line_to (draw_data, *st,
to_x, to_y);
}
/**
* hb_draw_quadratic_to:
* @dfuncs: draw functions
* @draw_data: associated draw data passed by the caller
* @st: current draw state
* @control_x: X component of control point
* @control_y: Y component of control point
* @to_x: X component of target point
* @to_y: Y component of target point
*
* Perform a "quadratic-to" draw operation.
*
* Since: 4.0.0
**/
void
hb_draw_quadratic_to (hb_draw_funcs_t *dfuncs, void *draw_data,
hb_draw_state_t *st,
float control_x, float control_y,
float to_x, float to_y)
{
dfuncs->quadratic_to (draw_data, *st,
control_x, control_y,
to_x, to_y);
}
/**
* hb_draw_cubic_to:
* @dfuncs: draw functions
* @draw_data: associated draw data passed by the caller
* @st: current draw state
* @control1_x: X component of first control point
* @control1_y: Y component of first control point
* @control2_x: X component of second control point
* @control2_y: Y component of second control point
* @to_x: X component of target point
* @to_y: Y component of target point
*
* Perform a "cubic-to" draw operation.
*
* Since: 4.0.0
**/
void
hb_draw_cubic_to (hb_draw_funcs_t *dfuncs, void *draw_data,
hb_draw_state_t *st,
float control1_x, float control1_y,
float control2_x, float control2_y,
float to_x, float to_y)
{
dfuncs->cubic_to (draw_data, *st,
control1_x, control1_y,
control2_x, control2_y,
to_x, to_y);
}
/**
* hb_draw_close_path:
* @dfuncs: draw functions
* @draw_data: associated draw data passed by the caller
* @st: current draw state
*
* Perform a "close-path" draw operation.
*
* Since: 4.0.0
**/
void
hb_draw_close_path (hb_draw_funcs_t *dfuncs, void *draw_data,
hb_draw_state_t *st)
{
dfuncs->close_path (draw_data, *st);
}
#endif