New functions to create a cairo_pattern_t corresponding to a solid color and a translucent color respectively. Document a few pattern functions.

This commit is contained in:
Kristian Høgsberg 2005-06-28 15:58:42 +00:00
parent e7442a4523
commit 5ab8a3085e
4 changed files with 171 additions and 29 deletions

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@ -1,3 +1,10 @@
2005-06-28 Kristian Høgsberg <krh@redhat.com>
* src/cairo-pattern.c (cairo_pattern_create_rgb)
(cairo_pattern_create_rgba): New functions to create a
cairo_pattern_t corresponding to a solid color and a translucent
color respectively. Document a few pattern functions.
2005-06-28 T Rowley <tim.rowley@gmail.com>
reviewed by: otaylor

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@ -294,6 +294,92 @@ _cairo_pattern_create_in_error (cairo_status_t status)
return &pattern->base;
}
/**
* cairo_pattern_create_rgb:
* @red: red component of the color
* @green: green component of the color
* @blue: blue component of the color
*
* Create a new cairo_pattern_t corresponding to a opaque color. The
* color components are floating point numbers in the range 0 to 1.
* If the values passed in are outside that range, they will be
* clamped.
*
* Return value: the newly created #cairo_pattern_t if succesful, or
* an error pattern in case of no memory. The caller owns the
* returned object and should call cairo_pattern_destroy() when
* finished with it.
*
* This function will always return a valid pointer, but if an error
* occurred the pattern status will be set to an error. To inspect
* the status of a pattern use cairo_pattern_status().
**/
cairo_pattern_t *
cairo_pattern_create_rgb (double red, double green, double blue)
{
cairo_color_t color;
_cairo_restrict_value (&red, 0.0, 1.0);
_cairo_restrict_value (&green, 0.0, 1.0);
_cairo_restrict_value (&blue, 0.0, 1.0);
_cairo_color_init_rgb (&color, red, green, blue);
return _cairo_pattern_create_solid (&color);
}
/**
* cairo_pattern_create_rgba:
* @red: red component of the color
* @green: green component of the color
* @blue: blue component of the color
* @alpha: alpha component of the color
*
* Create a new cairo_pattern_t corresponding to a translucent color.
* The color components are floating point numbers in the range 0 to
* 1. If the values passed in are outside that range, they will be
* clamped.
*
* Return value: the newly created #cairo_pattern_t if succesful, or
* an error pattern in case of no memory. The caller owns the
* returned object and should call cairo_pattern_destroy() when
* finished with it.
*
* This function will always return a valid pointer, but if an error
* occurred the pattern status will be set to an error. To inspect
* the status of a pattern use cairo_pattern_status().
**/
cairo_pattern_t *
cairo_pattern_create_rgba (double red, double green, double blue,
double alpha)
{
cairo_color_t color;
_cairo_restrict_value (&red, 0.0, 1.0);
_cairo_restrict_value (&green, 0.0, 1.0);
_cairo_restrict_value (&blue, 0.0, 1.0);
_cairo_restrict_value (&alpha, 0.0, 1.0);
_cairo_color_init_rgba (&color, red, green, blue, alpha);
return _cairo_pattern_create_solid (&color);
}
/**
* cairo_pattern_create_for_surface:
* @surface: the surface
*
* Create a new cairo_pattern_t for the given surface.
*
* Return value: the newly created #cairo_pattern_t if succesful, or
* an error pattern in case of no memory. The caller owns the
* returned object and should call cairo_pattern_destroy() when
* finished with it.
*
* This function will always return a valid pointer, but if an error
* occurred the pattern status will be set to an error. To inspect
* the status of a pattern use cairo_pattern_status().
**/
cairo_pattern_t *
cairo_pattern_create_for_surface (cairo_surface_t *surface)
{
@ -308,6 +394,28 @@ cairo_pattern_create_for_surface (cairo_surface_t *surface)
return &pattern->base;
}
/**
* cairo_pattern_create_linear:
* @x0: x coordinate of the start point
* @y0: y coordinate of the start point
* @x1: x coordinate of the end point
* @y1: y coordinate of the end point
*
* Create a new linear gradient cairo_pattern_t along the line defined
* by (x0, y0) and (x1, y1). Before using the gradient pattern, a
* number of color stops should be defined using
* cairo_pattern_add_color_stop_rgb() or
* cairo_pattern_add_color_stop_rgba().
*
* Return value: the newly created #cairo_pattern_t if succesful, or
* an error pattern in case of no memory. The caller owns the
* returned object and should call cairo_pattern_destroy() when
* finished with it.
*
* This function will always return a valid pointer, but if an error
* occurred the pattern status will be set to an error. To inspect
* the status of a pattern use cairo_pattern_status().
**/
cairo_pattern_t *
cairo_pattern_create_linear (double x0, double y0, double x1, double y1)
{
@ -322,6 +430,30 @@ cairo_pattern_create_linear (double x0, double y0, double x1, double y1)
return &pattern->base.base;
}
/**
* cairo_pattern_create_radial:
* @cx0: x coordinate for the center of the start circle
* @cy0: y coordinate for the center of the start circle
* @radius0: radius of the start cirle
* @cx1: x coordinate for the center of the end circle
* @cy1: y coordinate for the center of the end circle
* @radius1: radius of the end cirle
*
* Create a new radial gradient cairo_pattern_t between the two
* circles defined by (x0, y0, c0) and (x1, y1, c0). Before using the
* gradient pattern, a number of color stops should be defined using
* cairo_pattern_add_color_stop_rgb() or
* cairo_pattern_add_color_stop_rgba().
*
* Return value: the newly created #cairo_pattern_t if succesful, or
* an error pattern in case of no memory. The caller owns the
* returned object and should call cairo_pattern_destroy() when
* finished with it.
*
* This function will always return a valid pointer, but if an error
* occurred the pattern status will be set to an error. To inspect
* the status of a pattern use cairo_pattern_status().
**/
cairo_pattern_t *
cairo_pattern_create_radial (double cx0, double cy0, double radius0,
double cx1, double cy1, double radius1)
@ -337,6 +469,14 @@ cairo_pattern_create_radial (double cx0, double cy0, double radius0,
return &pattern->base.base;
}
/**
* cairo_pattern_reference:
* @pattern: a #cairo_pattern_t
*
* Increases the reference count on @pattern by one. This prevents
* @pattern from being destroyed until a matching call to
* cairo_pattern_destroy() is made.
**/
void
cairo_pattern_reference (cairo_pattern_t *pattern)
{
@ -364,6 +504,14 @@ cairo_pattern_status (cairo_pattern_t *pattern)
return pattern->status;
}
/**
* cairo_pattern_destroy:
* @pattern: a #cairo_pattern_t
*
* Decreases the reference count on @pattern by one. If the result is
* zero, then @pattern and all associated resources are freed. See
* cairo_pattern_reference().
**/
void
cairo_pattern_destroy (cairo_pattern_t *pattern)
{

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@ -320,18 +320,6 @@ cairo_set_operator (cairo_t *cr, cairo_operator_t op)
_cairo_error (cr, cr->status);
}
static void
_cairo_set_source_solid (cairo_t *cr, const cairo_color_t *color)
{
cairo_pattern_t *source;
source = _cairo_pattern_create_solid (color);
cairo_set_source (cr, source);
cairo_pattern_destroy (source);
}
/**
* cairo_set_source_rgb
* @cr: a cairo context
@ -350,20 +338,16 @@ _cairo_set_source_solid (cairo_t *cr, const cairo_color_t *color)
void
cairo_set_source_rgb (cairo_t *cr, double red, double green, double blue)
{
cairo_color_t color;
cairo_pattern_t *pattern;
if (cr->status) {
_cairo_error (cr, cr->status);
return;
}
_cairo_restrict_value (&red, 0.0, 1.0);
_cairo_restrict_value (&green, 0.0, 1.0);
_cairo_restrict_value (&blue, 0.0, 1.0);
_cairo_color_init_rgb (&color, red, green, blue);
_cairo_set_source_solid (cr, &color);
pattern = cairo_pattern_create_rgb (red, green, blue);
cairo_set_source (cr, pattern);
cairo_pattern_destroy (pattern);
}
/**
@ -387,21 +371,16 @@ cairo_set_source_rgba (cairo_t *cr,
double red, double green, double blue,
double alpha)
{
cairo_color_t color;
cairo_pattern_t *pattern;
if (cr->status) {
_cairo_error (cr, cr->status);
return;
}
_cairo_restrict_value (&red, 0.0, 1.0);
_cairo_restrict_value (&green, 0.0, 1.0);
_cairo_restrict_value (&blue, 0.0, 1.0);
_cairo_restrict_value (&alpha, 0.0, 1.0);
_cairo_color_init_rgba (&color, red, green, blue, alpha);
_cairo_set_source_solid (cr, &color);
pattern = cairo_pattern_create_rgba (red, green, blue, alpha);
cairo_set_source (cr, pattern);
cairo_pattern_destroy (pattern);
}
/**

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@ -992,6 +992,14 @@ cairo_image_surface_create_from_png_stream (cairo_read_func_t read_func,
#endif
/* Pattern creation functions */
cairo_pattern_t *
cairo_pattern_create_rgb (double red, double green, double blue);
cairo_pattern_t *
cairo_pattern_create_rgba (double red, double green, double blue,
double alpha);
cairo_pattern_t *
cairo_pattern_create_for_surface (cairo_surface_t *surface);