mutter/cogl/cogl-color.h
Robert Bragg 0f5f4e8645 cogl: improves header and coding style consistency
We've had complaints that our Cogl code/headers are a bit "special" so
this is a first pass at tidying things up by giving them some
consistency. These changes are all consistent with how new code in Cogl
is being written, but the style isn't consistently applied across all
code yet.

There are two parts to this patch; but since each one required a large
amount of effort to maintain tidy indenting it made sense to combine the
changes to reduce the time spent re indenting the same lines.

The first change is to use a consistent style for declaring function
prototypes in headers. Cogl headers now consistently use this style for
prototypes:

 return_type
 cogl_function_name (CoglType arg0,
                     CoglType arg1);

Not everyone likes this style, but it seems that most of the currently
active Cogl developers agree on it.

The second change is to constrain the use of redundant glib data types
in Cogl. Uses of gint, guint, gfloat, glong, gulong and gchar have all
been replaced with int, unsigned int, float, long, unsigned long and char
respectively. When talking about pixel data; use of guchar has been
replaced with guint8, otherwise unsigned char can be used.

The glib types that we continue to use for portability are gboolean,
gint{8,16,32,64}, guint{8,16,32,64} and gsize.

The general intention is that Cogl should look palatable to the widest
range of C programmers including those outside the Gnome community so
- especially for the public API - we want to minimize the number of
foreign looking typedefs.
2010-02-12 14:05:00 +00:00

323 lines
7.2 KiB
C

/*
* 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, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:cogl-color
* @short_description: A generic color definition
*
* #CoglColor is a simple structure holding the definition of a color such
* that it can be efficiently used by GL
*
* Since: 1.0
*/
#if !defined(__COGL_H_INSIDE__) && !defined(CLUTTER_COMPILATION)
#error "Only <cogl/cogl.h> can be included directly."
#endif
#ifndef __COGL_COLOR_H__
#define __COGL_COLOR_H__
#include <cogl/cogl-types.h>
G_BEGIN_DECLS
/**
* cogl_color_new:
*
* Creates a new (empty) color
*
* Return value: a newly-allocated #CoglColor. Use cogl_color_free()
* to free the allocated resources
*
* Since: 1.0
*/
CoglColor *
cogl_color_new (void);
/**
* cogl_color_copy:
* @color: the color to copy
*
* Creates a copy of @color
*
* Return value: a newly-allocated #CoglColor. Use cogl_color_free()
* to free the allocate resources
*
* Since: 1.0
*/
CoglColor *
cogl_color_copy (const CoglColor *color);
/**
* cogl_color_free:
* @color: the color to free
*
* Frees the resources allocated by cogl_color_new() and cogl_color_copy()
*
* Since: 1.0
*/
void
cogl_color_free (CoglColor *color);
/**
* cogl_color_set_from_4ub:
* @dest: return location for a #CoglColor
* @red: value of the red channel, between 0 and 255
* @green: value of the green channel, between 0 and 255
* @blue: value of the blue channel, between 0 and 255
* @alpha: value of the alpha channel, between 0 and 255
*
* Sets the values of the passed channels into a #CoglColor.
*
* Since: 1.0
*/
void
cogl_color_set_from_4ub (CoglColor *dest,
guint8 red,
guint8 green,
guint8 blue,
guint8 alpha);
/**
* cogl_color_set_from_4f:
* @dest: return location for a #CoglColor
* @red: value of the red channel, between 0 and %1.0
* @green: value of the green channel, between 0 and %1.0
* @blue: value of the blue channel, between 0 and %1.0
* @alpha: value of the alpha channel, between 0 and %1.0
*
* Sets the values of the passed channels into a #CoglColor
*
* Since: 1.0
*/
void
cogl_color_set_from_4f (CoglColor *dest,
float red,
float green,
float blue,
float alpha);
/**
* cogl_color_get_red_byte:
* @color: a #CoglColor
*
* Retrieves the red channel of @color as a byte value
* between 0 and 255
*
* Return value: the red channel of the passed color
*
* Since: 1.0
*/
unsigned char
cogl_color_get_red_byte (const CoglColor *color);
/**
* cogl_color_get_green_byte:
* @color: a #CoglColor
*
* Retrieves the green channel of @color as a byte value
* between 0 and 255
*
* Return value: the green channel of the passed color
*
* Since: 1.0
*/
unsigned char
cogl_color_get_green_byte (const CoglColor *color);
/**
* cogl_color_get_blue_byte:
* @color: a #CoglColor
*
* Retrieves the blue channel of @color as a byte value
* between 0 and 255
*
* Return value: the blue channel of the passed color
*
* Since: 1.0
*/
unsigned char
cogl_color_get_blue_byte (const CoglColor *color);
/**
* cogl_color_get_alpha_byte:
* @color: a #CoglColor
*
* Retrieves the alpha channel of @color as a byte value
* between 0 and 255
*
* Return value: the alpha channel of the passed color
*
* Since: 1.0
*/
unsigned char
cogl_color_get_alpha_byte (const CoglColor *color);
/**
* cogl_color_get_red_float:
* @color: a #CoglColor
*
* Retrieves the red channel of @color as a floating point
* value between 0.0 and 1.0
*
* Return value: the red channel of the passed color
*
* Since: 1.0
*/
float
cogl_color_get_red_float (const CoglColor *color);
/**
* cogl_color_get_green_float:
* @color: a #CoglColor
*
* Retrieves the green channel of @color as a floating point
* value between 0.0 and 1.0
*
* Return value: the green channel of the passed color
*
* Since: 1.0
*/
float
cogl_color_get_green_float (const CoglColor *color);
/**
* cogl_color_get_blue_float:
* @color: a #CoglColor
*
* Retrieves the blue channel of @color as a floating point
* value between 0.0 and 1.0
*
* Return value: the blue channel of the passed color
*
* Since: 1.0
*/
float
cogl_color_get_blue_float (const CoglColor *color);
/**
* cogl_color_get_alpha_float:
* @color: a #CoglColor
*
* Retrieves the alpha channel of @color as a floating point
* value between 0.0 and 1.0
*
* Return value: the alpha channel of the passed color
*
* Since: 1.0
*/
float
cogl_color_get_alpha_float (const CoglColor *color);
/**
* cogl_color_get_red:
* @color: a #CoglColor
*
* Retrieves the red channel of @color as a fixed point
* value between 0 and %1.0.
*
* Return value: the red channel of the passed color
*
* Since: 1.0
*/
float
cogl_color_get_red (const CoglColor *color);
/**
* cogl_color_get_green:
* @color: a #CoglColor
*
* Retrieves the green channel of @color as a fixed point
* value between 0 and %1.0.
*
* Return value: the green channel of the passed color
*
* Since: 1.0
*/
float
cogl_color_get_green (const CoglColor *color);
/**
* cogl_color_get_blue:
* @color: a #CoglColor
*
* Retrieves the blue channel of @color as a fixed point
* value between 0 and %1.0.
*
* Return value: the blue channel of the passed color
*
* Since: 1.0
*/
float
cogl_color_get_blue (const CoglColor *color);
/**
* cogl_color_get_alpha:
* @color: a #CoglColor
*
* Retrieves the alpha channel of @color as a fixed point
* value between 0 and %1.0.
*
* Return value: the alpha channel of the passed color
*
* Since: 1.0
*/
float
cogl_color_get_alpha (const CoglColor *color);
/**
* cogl_color_premultiply:
* @color: the color to premultiply
*
* Converts a non-premultiplied color to a pre-multiplied color. For
* example, semi-transparent red is (1.0, 0, 0, 0.5) when non-premultiplied
* and (0.5, 0, 0, 0.5) when premultiplied.
*
* Since: 1.0
*/
void
cogl_color_premultiply (CoglColor *color);
/**
* cogl_color_equal:
* @v1: a #CoglColor
* @v2: a #CoglColor
*
* Compares two #CoglColor<!-- -->s and checks if they are the same.
*
* This function can be passed to g_hash_table_new() as the @key_equal_func
* parameter, when using #CoglColor<!-- -->s as keys in a #GHashTable.
*
* Return value: %TRUE if the two colors are the same.
*
* Since: 1.0
*/
gboolean
cogl_color_equal (gconstpointer v1,
gconstpointer v2);
G_END_DECLS
#endif /* __COGL_COLOR_H__ */