cairo-utils.h revision b46549b5c715d24b315796f3dfb29748a4c0615c
/**
* @file
* Cairo integration helpers.
*//*
* Authors:
* Krzysztof Kosiński <tweenk.pl@gmail.com>
*
* Copyright (C) 2010 Authors
* Released under GNU GPL, read the file 'COPYING' for more information
*/
#ifndef SEEN_INKSCAPE_DISPLAY_CAIRO_UTILS_H
#define SEEN_INKSCAPE_DISPLAY_CAIRO_UTILS_H
#include <glib.h>
#include <cairomm/cairomm.h>
#include <2geom/forward.h>
#include "style.h"
struct SPColor;
struct _GdkPixbuf;
typedef struct _GdkPixbuf GdkPixbuf;
namespace Inkscape {
/**
* RAII idiom for Cairo groups.
* Groups are temporary surfaces used when rendering e.g. masks and opacity.
* Use this class to ensure that each group push is matched with a pop.
*/
class CairoGroup {
public:
CairoGroup(cairo_t *_ct);
~CairoGroup();
void push();
void push_with_content(cairo_content_t content);
cairo_pattern_t *pop();
Cairo::RefPtr<Cairo::Pattern> popmm();
void pop_to_source();
private:
cairo_t *ct;
bool pushed;
};
/** RAII idiom for Cairo state saving. */
class CairoSave {
public:
CairoSave(cairo_t *_ct, bool save=false)
: ct(_ct)
, saved(save)
{
if (save) {
cairo_save(ct);
}
}
void save() {
if (!saved) {
cairo_save(ct);
saved = true;
}
}
~CairoSave() {
if (saved)
cairo_restore(ct);
}
private:
cairo_t *ct;
bool saved;
};
/** Cairo context with Inkscape-specific operations. */
class CairoContext : public Cairo::Context {
public:
CairoContext(cairo_t *obj, bool ref = false);
void transform(Geom::Affine const &m);
void set_source_rgba32(guint32 color);
void append_path(Geom::PathVector const &pv);
static Cairo::RefPtr<CairoContext> create(Cairo::RefPtr<Cairo::Surface> const &target);
};
} // namespace Inkscape
/**
* Key for cairo_surface_t to keep track of current color interpolation value
* Only the address of the structure is used, it is never initialized. See:
* http://www.cairographics.org/manual/cairo-Types.html#cairo-user-data-key-t
*/
static cairo_user_data_key_t ci_key;
SPColorInterpolation get_cairo_surface_ci(cairo_surface_t *surface);
void set_cairo_surface_ci(cairo_surface_t *surface, SPColorInterpolation cif);
void copy_cairo_surface_ci(cairo_surface_t *in, cairo_surface_t *out);
void ink_cairo_set_source_color(cairo_t *ct, SPColor const &color, double opacity);
void ink_cairo_set_source_rgba32(cairo_t *ct, guint32 rgba);
void ink_cairo_transform(cairo_t *ct, Geom::Affine const &m);
void ink_cairo_pattern_set_matrix(cairo_pattern_t *cp, Geom::Affine const &m);
void ink_cairo_set_source_argb32_pixbuf(cairo_t *ct, GdkPixbuf *pb, double x, double y);
void ink_matrix_to_2geom(Geom::Affine &, cairo_matrix_t const &);
void ink_matrix_to_cairo(cairo_matrix_t &, Geom::Affine const &);
cairo_surface_t *ink_cairo_surface_copy(cairo_surface_t *s);
cairo_surface_t *ink_cairo_surface_create_identical(cairo_surface_t *s);
cairo_surface_t *ink_cairo_surface_create_same_size(cairo_surface_t *s, cairo_content_t c);
cairo_surface_t *ink_cairo_extract_alpha(cairo_surface_t *s);
cairo_surface_t *ink_cairo_surface_create_output(cairo_surface_t *image, cairo_surface_t *bg);
void ink_cairo_surface_blit(cairo_surface_t *src, cairo_surface_t *dest);
int ink_cairo_surface_get_width(cairo_surface_t *surface);
int ink_cairo_surface_get_height(cairo_surface_t *surface);
guint32 ink_cairo_surface_average_color(cairo_surface_t *surface);
void ink_cairo_surface_average_color(cairo_surface_t *surface, double &r, double &g, double &b, double &a);
void ink_cairo_surface_average_color_premul(cairo_surface_t *surface, double &r, double &g, double &b, double &a);
int ink_cairo_surface_srgb_to_linear(cairo_surface_t *surface);
int ink_cairo_surface_linear_to_srgb(cairo_surface_t *surface);
cairo_pattern_t *ink_cairo_pattern_create_checkerboard();
void convert_pixels_pixbuf_to_argb32(guchar *data, int w, int h, int rs);
void convert_pixels_argb32_to_pixbuf(guchar *data, int w, int h, int rs);
void convert_pixbuf_normal_to_argb32(GdkPixbuf *);
void convert_pixbuf_argb32_to_normal(GdkPixbuf *);
cairo_surface_t *ink_cairo_surface_create_for_argb32_pixbuf(GdkPixbuf *pb);
void ink_cairo_pixbuf_cleanup(guchar *pixels, void *surface);
G_GNUC_CONST guint32 argb32_from_pixbuf(guint32 in);
G_GNUC_CONST guint32 pixbuf_from_argb32(guint32 in);
/** Convert a pixel in 0xRRGGBBAA format to Cairo ARGB32 format. */
G_GNUC_CONST guint32 argb32_from_rgba(guint32 in);
G_GNUC_CONST inline guint32
premul_alpha(guint32 color, guint32 alpha)
{
guint32 temp = alpha * color + 128;
return (temp + (temp >> 8)) >> 8;
}
G_GNUC_CONST inline guint32
unpremul_alpha(guint32 color, guint32 alpha)
{
// NOTE: you must check for alpha != 0 yourself.
return (255 * color + alpha/2) / alpha;
}
// TODO: move those to 2Geom
void feed_pathvector_to_cairo (cairo_t *ct, Geom::PathVector const &pathv, Geom::Affine trans, Geom::OptRect area, bool optimize_stroke, double stroke_width);
void feed_pathvector_to_cairo (cairo_t *ct, Geom::PathVector const &pathv);
#define EXTRACT_ARGB32(px,a,r,g,b) \
guint32 a, r, g, b; \
a = ((px) & 0xff000000) >> 24; \
r = ((px) & 0x00ff0000) >> 16; \
g = ((px) & 0x0000ff00) >> 8; \
b = ((px) & 0x000000ff);
#define ASSEMBLE_ARGB32(px,a,r,g,b) \
guint32 px = (a << 24) | (r << 16) | (g << 8) | b;
namespace Inkscape {
namespace Display
{
inline void ExtractARGB32(guint32 px, guint32 &a, guint32 &r, guint32 &g, guint &b)
{
a = ((px) & 0xff000000) >> 24;
r = ((px) & 0x00ff0000) >> 16;
g = ((px) & 0x0000ff00) >> 8;
b = ((px) & 0x000000ff);
}
inline void ExtractRGB32(guint32 px, guint32 &r, guint32 &g, guint &b)
{
r = ((px) & 0x00ff0000) >> 16;
g = ((px) & 0x0000ff00) >> 8;
b = ((px) & 0x000000ff);
}
inline guint AssembleARGB32(guint32 a, guint32 r, guint32 g, guint32 b)
{
return (a << 24) | (r << 16) | (g << 8) | b;
}
} // namespace Display
} // namespace Inkscape
#endif // SEEN_INKSCAPE_DISPLAY_CAIRO_UTILS_H
/*
Local Variables:
mode:c++
c-file-style:"stroustrup"
c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
indent-tabs-mode:nil
fill-column:99
End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :