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RGtk2 (version 2.20.31)

cairo-pattern: cairo_pattern_t

Description

Sources for drawing

Arguments

Methods and Functions

cairoPatternAddColorStopRgb(pattern, offset, red, green, blue) cairoPatternAddColorStopRgba(pattern, offset, red, green, blue, alpha) cairoPatternGetColorStopCount(pattern) cairoPatternGetColorStopRgba(pattern, index) cairoPatternCreateRgb(red, green, blue) cairoPatternCreateRgba(red, green, blue, alpha) cairoPatternGetRgba(pattern) cairoPatternCreateForSurface(surface) cairoPatternGetSurface(pattern) cairoPatternCreateLinear(x0, y0, x1, y1) cairoPatternGetLinearPoints(pattern) cairoPatternCreateRadial(cx0, cy0, radius0, cx1, cy1, radius1) cairoPatternGetRadialCircles(pattern) cairoPatternStatus(pattern) cairoPatternSetExtend(pattern, extend) cairoPatternGetExtend(pattern) cairoPatternSetFilter(pattern, filter) cairoPatternGetFilter(pattern) cairoPatternSetMatrix(pattern, matrix) cairoPatternGetMatrix(pattern, matrix) cairoPatternGetType(pattern) cairoPatternSetUserData(pattern, key, user.data) cairoPatternGetUserData(pattern, key) cairoPattern(red, green, blue, alpha, surface, x0, y0, x1, y1, cx0, cy0, radius0, cx1, cy1, radius1)

Detailed Description

CairoPattern is the paint with which cairo draws. The primary use of patterns is as the source for all cairo drawing operations, although they can also be used as masks, that is, as the brush too. A cairo pattern is created by using one of the many constructors, of the form cairo_pattern_create_type() or implicitly through cairo_set_source_type() functions.

Structures

Convenient Construction

cairoPattern is the result of collapsing the constructors of cairo_pattern_t (cairoPatternCreateRgb, cairoPatternCreateRgba, cairoPatternCreateForSurface, cairoPatternCreateLinear, cairoPatternCreateRadial) and accepts a subset of its arguments matching the required arguments of one of its delegate constructors.

Enums and Flags

CairoExtend
CairoExtend is used to describe how pattern color/alpha will be determined for areas "outside" the pattern's natural area, (for example, outside the surface bounds or outside the gradient geometry). The default extend mode is CAIRO_EXTEND_NONE for surface patterns and CAIRO_EXTEND_PAD for gradient patterns. New entries may be added in future versions.
none
pixels outside of the source pattern are fully transparent
repeat
the pattern is tiled by repeating
reflect
the pattern is tiled by reflecting at the edges (Implemented for surface patterns since 1.6)
CairoFilter
CairoFilter is used to indicate what filtering should be applied when reading pixel values from patterns. See cairoPatternSetSource() for indicating the desired filter to be used with a particular pattern.
fast
A high-performance filter, with quality similar to CAIRO_FILTER_NEAREST
good
A reasonable-performance filter, with quality similar to CAIRO_FILTER_BILINEAR
best
The highest-quality available, performance may not be suitable for interactive use.
nearest
Nearest-neighbor filtering
bilinear
Linear interpolation in two dimensions
gaussian
This filter value is currently unimplemented, and should not be used in current code.
CairoPatternType
CairoPatternType is used to describe the type of a given pattern. The type of a pattern is determined by the function used to create it. The cairoPatternCreateRgb and cairoPatternCreateRgba functions create SOLID patterns. The remaining cairo_pattern_create functions map to pattern types in obvious ways. The pattern type can be queried with cairoPatternGetType Most CairoPattern functions can be called with a pattern of any type, (though trying to change the extend or filter for a solid pattern will have no effect). A notable exception is cairoPatternAddColorStopRgb and cairoPatternAddColorStopRgba which must only be called with gradient patterns (either LINEAR or RADIAL). Otherwise the pattern will be shutdown and put into an error state. New entries may be added in future versions. Since 1.2
solid
The pattern is a solid (uniform) color. It may be opaque or translucent.
surface
The pattern is a based on a surface (an image).
linear
The pattern is a linear gradient.
radial
The pattern is a radial gradient.

References

http://www.cairographics.org/manual/cairo-pattern.html