Initial commit of Cairo renderer for PDF export

(bzr r1730)

1 files changed, 198 insertions, 0 deletions

diff --git a/src/extension/internal/cairo-render-context.h b/src/extension/internal/cairo-render-context.h
new file mode 100644
index 000000000..7659c3518
--- /dev/null
+++ b/src/extension/internal/cairo-render-context.h
@@ -0,0 +1,198 @@
+#ifndef EXTENSION_INTERNAL_CAIRO_RENDER_CONTEXT_H_SEEN
+#define EXTENSION_INTERNAL_CAIRO_RENDER_CONTEXT_H_SEEN
+
+/** \file
+ * Declaration of CairoRenderContext, a class used for rendering with Cairo.
+ */
+/*
+ * Authors:
+ * 	   Miklos Erdelyi <erdelyim@gmail.com>
+ *
+ * Copyright (C) 2006 Miklos Erdelyi
+ * 
+ * Licensed under GNU GPL
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#ifdef HAVE_CAIRO_PDF
+
+#include "extension/extension.h"
+#include <set>
+#include <string>
+
+#include "libnr/nr-path.h"
+#include <libnr/nr-matrix-ops.h>
+
+#include "style.h"
+
+#include <cairo.h>
+
+class SPClipPath;
+class SPMask;
+
+namespace Inkscape {
+namespace Extension {
+namespace Internal {
+
+class CairoRenderer;
+class CairoRenderContext;
+class CairoRenderState;
+class CairoGlyphInfo;
+
+// Holds info for rendering a glyph
+struct CairoGlyphInfo {
+    unsigned long index;
+    double x;
+    double y;
+};
+
+struct CairoRenderState {
+    unsigned int merge_opacity : 1;     // whether fill/stroke opacity can be mul'd with item opacity
+    unsigned int need_layer : 1;
+    unsigned int has_overflow : 1;
+    unsigned int parent_has_userspace : 1;  // whether the parent's ctm should be applied
+    float opacity;
+
+    SPClipPath *clip_path;
+    SPMask* mask;
+
+    NRMatrix transform;     // the CTM
+};
+
+class CairoRenderContext {
+    friend class CairoRenderer;
+public:
+    CairoRenderContext *cloneMe(void) const;
+    CairoRenderContext *cloneMe(double width, double height) const;
+    bool finish(void);
+
+    CairoRenderer *getRenderer(void) const;
+    cairo_t *getCairoContext(void) const;
+
+    typedef enum CairoRenderMode {
+        RENDER_MODE_NORMAL,
+        RENDER_MODE_CLIP
+    };
+    
+    typedef enum CairoClipMode {
+        CLIP_MODE_PATH,
+        CLIP_MODE_MASK
+    };
+    
+    bool setImageTarget(cairo_format_t format);
+    bool setPdfTarget(gchar const *utf8_fn);
+
+    /** Creates the cairo_surface_t for the context with the
+    given width, height and with the currently set target
+    surface type. */
+    bool setupSurface(double width, double height);
+
+    cairo_surface_t *getSurface(void);
+
+    /** Saves the contents of the context to a PNG file. */
+    bool saveAsPng(const char *file_name);
+
+    /* Render/clip mode setting/query */
+    void setRenderMode(CairoRenderMode mode);
+    CairoRenderMode getRenderMode(void) const;
+    void setClipMode(CairoClipMode mode);
+    CairoClipMode getClipMode(void) const;
+    
+    void addBpath(NArtBpath const *bp);
+    void setBpath(NArtBpath const *bp);
+    
+    void pushLayer(void);
+    void popLayer(void);
+
+    /* Graphics state manipulation */
+    void pushState(void);
+    void popState(void);
+    CairoRenderState *getCurrentState(void) const;
+    CairoRenderState *getParentState(void) const;
+    void setStateForStyle(SPStyle const *style);
+
+    void transform(NRMatrix const *transform);
+    void setTransform(NRMatrix const *transform);
+    void getTransform(NRMatrix *copy) const;
+    void getParentTransform(NRMatrix *copy) const;
+
+    /* Clipping methods */
+    void addClipPath(NArtBpath const *bp, SPIEnum const *fill_rule);
+    void addClippingRect(double x, double y, double width, double height);
+
+    /* Rendering methods */
+    bool renderPath(NRBPath const *bpath, SPStyle const *style, NRRect const *pbox);
+    bool renderImage(unsigned char *px, unsigned int w, unsigned int h, unsigned int rs,
+                     NRMatrix const *image_transform, SPStyle const *style);
+    bool renderGlyphtext(PangoFont *font, NRMatrix const *font_matrix,
+                         std::vector<CairoGlyphInfo> const &glyphtext, SPStyle const *style);
+
+    /* More general rendering methods will have to be added (like fill, stroke) */
+
+protected:
+    CairoRenderContext(CairoRenderer *renderer);
+    ~CairoRenderContext(void);
+    
+    float _width;
+    float _height;
+    unsigned short _dpi;
+    
+    FILE *_stream;
+    
+    unsigned int _is_valid : 1;
+    unsigned int _vector_based_target : 1;
+
+    cairo_t *_cr;
+    cairo_surface_t *_surface;
+    cairo_surface_type_t _target;
+    cairo_format_t _target_format;
+    PangoLayout *_layout;
+    
+    unsigned int _clip_rule : 8;
+    unsigned int _clip_winding_failed : 1;
+    
+    GSList *_state_stack;
+    CairoRenderState *_state;    // the current state
+    
+    CairoRenderer *_renderer;
+
+    CairoRenderMode _render_mode;
+    CairoClipMode _clip_mode;
+
+    cairo_pattern_t *_createPatternForPaintServer(SPPaintServer const *const paintserver,
+                                                  NRRect const *pbox, float alpha);
+    cairo_pattern_t *_createPatternPainter(SPPaintServer const *const paintserver, NRRect const *pbox);
+   
+    unsigned int _showGlyphs(cairo_t *cr, PangoFont *font, std::vector<CairoGlyphInfo> const &glyphtext, bool is_stroke);
+
+    void _setFillStyle(SPStyle const *style, NRRect const *pbox);
+    void _setStrokeStyle(SPStyle const *style, NRRect const *pbox);
+    
+    void _initCairoMatrix(cairo_matrix_t *matrix, NRMatrix const *transform);
+    void _concatTransform(cairo_t *cr, double xx, double yx, double xy, double yy, double x0, double y0);
+    void _concatTransform(cairo_t *cr, NRMatrix const *transform);
+
+    CairoRenderState *_createState(void);
+};
+
+}  /* namespace Internal */
+}  /* namespace Extension */
+}  /* namespace Inkscape */
+
+#endif /* HAVE_CAIRO_PDF */
+
+#endif /* !EXTENSION_INTERNAL_CAIRO_RENDER_CONTEXT_H_SEEN */
+
+/*
+  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 :