/* -*- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -*- */ /* cairo - a vector graphics library with display and print output * * Copyright (c) 2008 M Joonas Pihlaja * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, * copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following * conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. */ #ifndef CAIRO_SPANS_PRIVATE_H #define CAIRO_SPANS_PRIVATE_H #include "cairo-types-private.h" #include "cairo-compiler-private.h" /* Number of bits of precision used for alpha. */ #define CAIRO_SPANS_UNIT_COVERAGE_BITS 8 #define CAIRO_SPANS_UNIT_COVERAGE ((1 << CAIRO_SPANS_UNIT_COVERAGE_BITS)-1) /* A structure representing an open-ended horizontal span of constant * pixel coverage. */ typedef struct _cairo_half_open_span { int32_t x; /* The inclusive x-coordinate of the start of the span. */ uint8_t coverage; /* The pixel coverage for the pixels to the right. */ uint8_t inverse; /* between regular mask and clip */ } cairo_half_open_span_t; /* Span renderer interface. Instances of renderers are provided by * surfaces if they want to composite spans instead of trapezoids. */ typedef struct _cairo_span_renderer cairo_span_renderer_t; struct _cairo_span_renderer { /* Private status variable. */ cairo_status_t status; /* Called to destroy the renderer. */ cairo_destroy_func_t destroy; /* Render the spans on row y of the destination by whatever compositing * method is required. */ cairo_status_t (*render_rows) (void *abstract_renderer, int y, int height, const cairo_half_open_span_t *coverages, unsigned num_coverages); /* Called after all rows have been rendered to perform whatever * final rendering step is required. This function is called just * once before the renderer is destroyed. */ cairo_status_t (*finish) (void *abstract_renderer); }; /* Scan converter interface. */ typedef struct _cairo_scan_converter cairo_scan_converter_t; struct _cairo_scan_converter { /* Destroy this scan converter. */ cairo_destroy_func_t destroy; /* Generates coverage spans for rows for the added edges and calls * the renderer function for each row. After generating spans the * only valid thing to do with the converter is to destroy it. */ cairo_status_t (*generate) (void *abstract_converter, cairo_span_renderer_t *renderer); /* Private status. Read with _cairo_scan_converter_status(). */ cairo_status_t status; }; /* Scan converter constructors. */ cairo_private cairo_scan_converter_t * _cairo_tor_scan_converter_create (int xmin, int ymin, int xmax, int ymax, cairo_fill_rule_t fill_rule, cairo_antialias_t antialias); cairo_private cairo_status_t _cairo_tor_scan_converter_add_polygon (void *converter, const cairo_polygon_t *polygon); cairo_private cairo_scan_converter_t * _cairo_tor22_scan_converter_create (int xmin, int ymin, int xmax, int ymax, cairo_fill_rule_t fill_rule, cairo_antialias_t antialias); cairo_private cairo_status_t _cairo_tor22_scan_converter_add_polygon (void *converter, const cairo_polygon_t *polygon); cairo_private cairo_scan_converter_t * _cairo_mono_scan_converter_create (int xmin, int ymin, int xmax, int ymax, cairo_fill_rule_t fill_rule); cairo_private cairo_status_t _cairo_mono_scan_converter_add_polygon (void *converter, const cairo_polygon_t *polygon); cairo_private cairo_scan_converter_t * _cairo_clip_tor_scan_converter_create (cairo_clip_t *clip, cairo_polygon_t *polygon, cairo_fill_rule_t fill_rule, cairo_antialias_t antialias); typedef struct _cairo_rectangular_scan_converter { cairo_scan_converter_t base; cairo_box_t extents; struct _cairo_rectangular_scan_converter_chunk { struct _cairo_rectangular_scan_converter_chunk *next; void *base; int count; int size; } chunks, *tail; char buf[CAIRO_STACK_BUFFER_SIZE]; int num_rectangles; } cairo_rectangular_scan_converter_t; cairo_private void _cairo_rectangular_scan_converter_init (cairo_rectangular_scan_converter_t *self, const cairo_rectangle_int_t *extents); cairo_private cairo_status_t _cairo_rectangular_scan_converter_add_box (cairo_rectangular_scan_converter_t *self, const cairo_box_t *box, int dir); typedef struct _cairo_botor_scan_converter { cairo_scan_converter_t base; cairo_box_t extents; cairo_fill_rule_t fill_rule; int xmin, xmax; struct _cairo_botor_scan_converter_chunk { struct _cairo_botor_scan_converter_chunk *next; void *base; int count; int size; } chunks, *tail; char buf[CAIRO_STACK_BUFFER_SIZE]; int num_edges; } cairo_botor_scan_converter_t; cairo_private void _cairo_botor_scan_converter_init (cairo_botor_scan_converter_t *self, const cairo_box_t *extents, cairo_fill_rule_t fill_rule); /* cairo-spans.c: */ cairo_private cairo_scan_converter_t * _cairo_scan_converter_create_in_error (cairo_status_t error); cairo_private cairo_status_t _cairo_scan_converter_status (void *abstract_converter); cairo_private cairo_status_t _cairo_scan_converter_set_error (void *abstract_converter, cairo_status_t error); cairo_private cairo_span_renderer_t * _cairo_span_renderer_create_in_error (cairo_status_t error); cairo_private cairo_status_t _cairo_span_renderer_status (void *abstract_renderer); /* Set the renderer into an error state. This sets all the method * pointers except ->destroy() of the renderer to no-op * implementations that just return the error status. */ cairo_private cairo_status_t _cairo_span_renderer_set_error (void *abstract_renderer, cairo_status_t error); cairo_private cairo_status_t _cairo_surface_composite_polygon (cairo_surface_t *surface, cairo_operator_t op, const cairo_pattern_t *pattern, cairo_fill_rule_t fill_rule, cairo_antialias_t antialias, const cairo_composite_rectangles_t *rects, cairo_polygon_t *polygon, cairo_region_t *clip_region); #endif /* CAIRO_SPANS_PRIVATE_H */