mutter/cogl/cogl-path.h

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/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2008,2009 Intel Corporation.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
*
*/
#if !defined(__COGL_H_INSIDE__) && !defined(COGL_COMPILATION)
#error "Only <cogl/cogl.h> can be included directly."
#endif
#ifndef __COGL_PATH_H__
#define __COGL_PATH_H__
#include <cogl/cogl-types.h>
COGL_BEGIN_DECLS
/**
* SECTION:cogl-paths
* @short_description: Functions for constructing and drawing 2D paths.
*
* There are two levels on which drawing with cogl-paths can be used.
* The highest level functions construct various simple primitive
* shapes to be either filled or stroked. Using a lower-level set of
* functions more complex and arbitrary paths can be constructed by
* concatenating straight line, bezier curve and arc segments.
*
* When constructing arbitrary paths, the current pen location is
* initialized using the move_to command. The subsequent path segments
* implicitly use the last pen location as their first vertex and move
* the pen location to the last vertex they produce at the end. Also
* there are special versions of functions that allow specifying the
* vertices of the path segments relative to the last pen location
* rather then in the absolute coordinates.
*/
typedef struct _CoglPath CoglPath;
#define COGL_PATH(obj) ((CoglPath *)(obj))
/**
* CoglPathFillRule:
* @COGL_PATH_FILL_RULE_NON_ZERO: Each time the line crosses an edge of
* the path from left to right one is added to a counter and each time
* it crosses from right to left the counter is decremented. If the
* counter is non-zero then the point will be filled. See <xref
* linkend="fill-rule-non-zero"/>.
* @COGL_PATH_FILL_RULE_EVEN_ODD: If the line crosses an edge of the
* path an odd number of times then the point will filled, otherwise
* it won't. See <xref linkend="fill-rule-even-odd"/>.
*
* #CoglPathFillRule is used to determine how a path is filled. There
* are two options - 'non-zero' and 'even-odd'. To work out whether any
* point will be filled imagine drawing an infinetely long line in any
* direction from that point. The number of times and the direction
* that the edges of the path crosses this line determines whether the
* line is filled as described below. Any open sub paths are treated
* as if there was an extra line joining the first point and the last
* point.
*
* The default fill rule is %COGL_PATH_FILL_RULE_EVEN_ODD. The fill
* rule is attached to the current path so preserving a path with
* cogl_get_path() also preserves the fill rule. Calling
* cogl_path_new() resets the current fill rule to the default.
*
* <figure id="fill-rule-non-zero">
* <title>Example of filling various paths using the non-zero rule</title>
* <graphic fileref="fill-rule-non-zero.png" format="PNG"/>
* </figure>
*
* <figure id="fill-rule-even-odd">
* <title>Example of filling various paths using the even-odd rule</title>
* <graphic fileref="fill-rule-even-odd.png" format="PNG"/>
* </figure>
*
* Since: 1.4
*/
typedef enum {
COGL_PATH_FILL_RULE_NON_ZERO,
COGL_PATH_FILL_RULE_EVEN_ODD
} CoglPathFillRule;
COGL_END_DECLS
Add -Wmissing-declarations to maintainer flags and fix problems This option to GCC makes it give a warning whenever a global function is defined without a declaration. This should catch cases were we've defined a function but forgot to put it in a header. In that case it is either only used within one file so we should make it static or we should declare it in a header. The following changes where made to fix problems: • Some functions were made static • cogl-path.h (the one containing the 1.0 API) was split into two files, one defining the functions and one defining the enums so that cogl-path.c can include the enum and function declarations from the 2.0 API as well as the function declarations from the 1.0 API. • cogl2-clip-state has been removed. This only had one experimental function called cogl_clip_push_from_path but as this is unstable we might as well remove it favour of the equivalent cogl_framebuffer_* API. • The GLX, SDL and WGL winsys's now have a private header to define their get_vtable function instead of directly declaring in the C file where it is called. • All places that were calling COGL_OBJECT_DEFINE need to have the cogl_is_whatever function declared so these have been added either as a public function or in a private header. • Some files that were not including the header containing their function declarations have been fixed to do so. • Any unused error quark functions have been removed. If we later want them we should add them back one by one and add a declaration for them in a header. • _cogl_is_framebuffer has been renamed to cogl_is_framebuffer and made a public function with a declaration in cogl-framebuffer.h • Similarly for CoglOnscreen. • cogl_vdraw_indexed_attributes is called cogl_framebuffer_vdraw_indexed_attributes in the header. The definition has been changed to match the header. • cogl_index_buffer_allocate has been removed. This had no declaration and I'm not sure what it's supposed to do. • CoglJournal has been changed to use the internal CoglObject macro so that it won't define an exported cogl_is_journal symbol. • The _cogl_blah_pointer_from_handle functions have been removed. CoglHandle isn't used much anymore anyway and in the few places where it is used I think it's safe to just use the implicit cast from void* to the right type. • The test-utils.h header for the conformance tests explicitly disables the -Wmissing-declaration option using a pragma because all of the tests declare their main function without a header. Any mistakes relating to missing declarations aren't really important for the tests. • cogl_quaternion_init_from_quaternion and init_from_matrix have been given declarations in cogl-quaternion.h Reviewed-by: Robert Bragg <robert@linux.intel.com>
2012-03-06 13:21:28 -05:00
#include "cogl-path-functions.h"
#endif /* __COGL_PATH_H__ */