Initial commit of Cairo renderer for PDF export

diff --git a/src/extension/internal/cairo-renderer.cpp b/src/extension/internal/cairo-renderer.cpp
new file mode 100644 (file)
index 0000000..bad3cb5
--- /dev/null
+++ b/src/extension/internal/cairo-renderer.cpp
@@ -0,0 +1,614 @@
+#define __SP_CAIRO_RENDERER_C__
+
+/** \file
+ * Rendering with Cairo.
+ */
+/*
+ * Author:
+ *   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
+
+#ifndef PANGO_ENABLE_BACKEND
+#define PANGO_ENABLE_BACKEND
+#endif
+
+#ifndef PANGO_ENABLE_ENGINE
+#define PANGO_ENABLE_ENGINE
+#endif
+
+
+#include <signal.h>
+#include <errno.h>
+
+#include <libnr/n-art-bpath.h>
+#include <libnr/nr-matrix-ops.h>
+#include <libnr/nr-matrix-fns.h>
+#include <libnr/nr-matrix-translate-ops.h>
+#include <libnr/nr-scale-matrix-ops.h>
+
+#include <glib/gmem.h>
+
+#include <glibmm/i18n.h>
+#include "display/nr-arena.h"
+#include "display/nr-arena-item.h"
+#include "display/nr-arena-group.h"
+#include "display/curve.h"
+#include "display/canvas-bpath.h"
+#include "sp-item.h"
+#include "sp-item-group.h"
+#include "marker-status.h"
+#include "style.h"
+#include "sp-marker.h"
+#include "sp-linear-gradient.h"
+#include "sp-radial-gradient.h"
+#include "sp-root.h"
+#include "sp-shape.h"
+#include "sp-use.h"
+#include "sp-text.h"
+#include "sp-flowtext.h"
+#include "sp-image.h"
+#include "sp-symbol.h"
+#include "sp-pattern.h"
+#include "sp-mask.h"
+#include "sp-clippath.h"
+
+#include <unit-constants.h>
+
+#include "cairo-renderer.h"
+#include "cairo-render-context.h"
+#include "extension/system.h"
+
+#include "io/sys.h"
+
+#include <cairo.h>
+
+// include support for only the compiled-in surface types
+#ifdef CAIRO_HAS_PDF_SURFACE
+#include <cairo-pdf.h>
+#endif
+#ifdef CAIRO_HAS_PS_SURFACE
+#include <cairo-ps.h>
+#endif
+
+//#define TRACE(_args) g_printf _args
+#define TRACE
+
+// FIXME: expose these from sp-clippath/mask.cpp
+struct SPClipPathView {
+    SPClipPathView *next;
+    unsigned int key;
+    NRArenaItem *arenaitem;
+    NRRect bbox;
+};
+
+struct SPMaskView {
+    SPMaskView *next;
+    unsigned int key;
+    NRArenaItem *arenaitem;
+    NRRect bbox;
+};
+
+namespace Inkscape {
+namespace Extension {
+namespace Internal {
+
+CairoRenderer::CairoRenderer(void)
+{}
+
+CairoRenderer::~CairoRenderer(void)
+{
+    /* restore default signal handling for SIGPIPE */
+#if !defined(_WIN32) && !defined(__WIN32__)
+    (void) signal(SIGPIPE, SIG_DFL);
+#endif
+
+    return;
+}
+
+CairoRenderContext*
+CairoRenderer::createContext(void)
+{
+    CairoRenderContext *new_context = new CairoRenderContext(this);
+    g_assert( new_context != NULL );
+
+    new_context->_state_stack = NULL;
+    new_context->_state = NULL;
+
+    // create initial render state
+    CairoRenderState *state = new_context->_createState();
+    nr_matrix_set_identity(&state->transform);
+    new_context->_state_stack = g_slist_prepend(new_context->_state_stack, state);
+    new_context->_state = state;
+
+    return new_context;
+}
+
+void
+CairoRenderer::destroyContext(CairoRenderContext *ctx)
+{
+    delete ctx;    
+}
+
+/*
+
+Here comes the rendering part which could be put into the 'render' methods of SPItems'
+
+*/
+
+/* The below functions are copy&pasted plus slightly modified from *_invoke_print functions. */
+static void sp_item_invoke_render(SPItem *item, CairoRenderContext *ctx);
+static void sp_group_render(SPItem *item, CairoRenderContext *ctx);
+static void sp_use_render(SPItem *item, CairoRenderContext *ctx);
+static void sp_shape_render(SPItem *item, CairoRenderContext *ctx);
+static void sp_text_render(SPItem *item, CairoRenderContext *ctx);
+static void sp_flowtext_render(SPItem *item, CairoRenderContext *ctx);
+static void sp_image_render(SPItem *item, CairoRenderContext *ctx);
+static void sp_symbol_render(SPItem *item, CairoRenderContext *ctx);
+
+static void sp_shape_render (SPItem *item, CairoRenderContext *ctx)
+{
+    NRRect pbox;
+
+    SPShape *shape = SP_SHAPE(item);
+
+    if (!shape->curve) return;
+
+    /* fixme: Think (Lauris) */
+    sp_item_invoke_bbox(item, &pbox, NR::identity(), TRUE);
+    NR::Matrix const i2d = sp_item_i2d_affine(item);
+
+    SPStyle* style = SP_OBJECT_STYLE (item);
+    CairoRenderer *renderer = ctx->getRenderer();
+
+    NRBPath bp;
+    bp.path = SP_CURVE_BPATH(shape->curve);
+
+    ctx->renderPath(&bp, style, &pbox);
+
+    for (NArtBpath* bp = SP_CURVE_BPATH(shape->curve); bp->code != NR_END; bp++) {
+        for (int m = SP_MARKER_LOC_START; m < SP_MARKER_LOC_QTY; m++) {
+            if (sp_shape_marker_required (shape, m, bp)) {
+
+                SPMarker* marker = SP_MARKER (shape->marker[m]);
+                SPItem* marker_item = sp_item_first_item_child (SP_OBJECT (shape->marker[m]));
+
+                NR::Matrix tr(sp_shape_marker_get_transform(shape, bp));
+
+                if (marker->markerUnits == SP_MARKER_UNITS_STROKEWIDTH) {
+                    tr = NR::scale(style->stroke_width.computed) * tr;
+                }
+
+                tr = marker_item->transform * marker->c2p * tr;
+
+                NR::Matrix old_tr = marker_item->transform;
+                marker_item->transform = tr;
+                renderer->renderItem (ctx, marker_item);
+                marker_item->transform = old_tr;
+            }
+        }
+    }
+}
+
+static void sp_group_render(SPItem *item, CairoRenderContext *ctx)
+{
+    SPGroup *group = SP_GROUP(item);
+    CairoRenderer *renderer = ctx->getRenderer();
+    TRACE(("group op: %f\n", SP_SCALE24_TO_FLOAT(SP_OBJECT_STYLE(item)->opacity.value)));
+    
+    GSList *l = g_slist_reverse(group->childList(false));
+    while (l) {
+        SPObject *o = SP_OBJECT (l->data);
+        if (SP_IS_ITEM(o)) {
+            renderer->renderItem (ctx, SP_ITEM (o));
+        }        
+        l = g_slist_remove (l, o);
+    }
+}
+
+static void sp_use_render(SPItem *item, CairoRenderContext *ctx)
+{
+    bool translated = false;
+    NRMatrix tp;
+    SPUse *use = SP_USE(item);
+    CairoRenderer *renderer = ctx->getRenderer();
+
+    if ((use->x._set && use->x.computed != 0) || (use->y._set && use->y.computed != 0)) {
+        nr_matrix_set_translate(&tp, use->x.computed, use->y.computed);
+        ctx->pushState();
+        ctx->transform(&tp);
+        translated = true;
+    }
+
+    if (use->child && SP_IS_ITEM(use->child)) {
+        renderer->renderItem(ctx, SP_ITEM(use->child));
+    }
+
+    if (translated) {
+        ctx->popState();
+    }
+}
+
+static void sp_text_render(SPItem *item, CairoRenderContext *ctx)
+{
+    SPText *group = SP_TEXT (item);
+    group->layout.showGlyphs(ctx);
+}
+
+static void sp_flowtext_render(SPItem *item, CairoRenderContext *ctx)
+{
+    SPFlowtext *group = SP_FLOWTEXT(item);
+    group->layout.showGlyphs(ctx);
+}
+
+static void sp_image_render(SPItem *item, CairoRenderContext *ctx)
+{
+    SPImage *image;
+    NRMatrix tp, s, t;
+    guchar *px;
+    int w, h, rs;
+
+    image = SP_IMAGE (item);
+
+    if (!image->pixbuf) return;
+    if ((image->width.computed <= 0.0) || (image->height.computed <= 0.0)) return;
+
+    px = gdk_pixbuf_get_pixels (image->pixbuf);
+    w = gdk_pixbuf_get_width (image->pixbuf);
+    h = gdk_pixbuf_get_height (image->pixbuf);
+    rs = gdk_pixbuf_get_rowstride (image->pixbuf);
+
+    double x = image->x.computed;
+    double y = image->y.computed;
+    double width = image->width.computed;
+    double height = image->height.computed;
+
+    if (image->aspect_align != SP_ASPECT_NONE) {
+        calculatePreserveAspectRatio (image->aspect_align, image->aspect_clip, (double)w, (double)h,
+                                                     &x, &y, &width, &height);
+    }
+    
+    if (image->aspect_clip == SP_ASPECT_SLICE && !ctx->getCurrentState()->has_overflow) {
+        ctx->addClippingRect(image->x.computed, image->y.computed, image->width.computed, image->height.computed);
+    }
+
+    nr_matrix_set_translate (&tp, x, y);    
+    nr_matrix_set_scale (&s, width / (double)w, height / (double)h);
+    nr_matrix_multiply (&t, &s, &tp);
+
+    ctx->renderImage (px, w, h, rs, &t, SP_OBJECT_STYLE (item));
+}
+
+static void sp_symbol_render(SPItem *item, CairoRenderContext *ctx)
+{
+    SPSymbol *symbol = SP_SYMBOL(item);
+    if (!SP_OBJECT_IS_CLONED (symbol))
+        return;
+    
+    /* Cloned <symbol> is actually renderable */
+    ctx->pushState();
+    ctx->transform(&symbol->c2p);
+        
+    // apply viewbox if set
+    if (0 /*symbol->viewBox_set*/) {
+        NRMatrix vb2user;
+        double x, y, width, height;
+        double view_width, view_height;
+        x = 0.0;
+        y = 0.0;
+        width = 1.0;
+        height = 1.0;
+        
+        view_width = symbol->viewBox.x1 - symbol->viewBox.x0;
+        view_height = symbol->viewBox.y1 - symbol->viewBox.y0;
+        
+        calculatePreserveAspectRatio(symbol->aspect_align, symbol->aspect_clip, view_width, view_height,
+                                     &x, &y,&width, &height);
+
+        // [itemTransform *] translate(x, y) * scale(w/vw, h/vh) * translate(-vx, -vy);
+        nr_matrix_set_identity(&vb2user);
+        vb2user[0] = width / view_width;
+        vb2user[3] = height / view_height;
+        vb2user[4] = x - symbol->viewBox.x0 * vb2user[0];
+        vb2user[5] = y - symbol->viewBox.y0 * vb2user[3];
+
+        ctx->transform(&vb2user);
+    }
+    
+    sp_group_render(item, ctx);
+    ctx->popState();
+}
+
+static void sp_root_render(SPItem *item, CairoRenderContext *ctx)
+{
+    SPRoot *root = SP_ROOT(item);
+    CairoRenderer *renderer = ctx->getRenderer();
+
+    if (!ctx->getCurrentState()->has_overflow && SP_OBJECT(item)->parent)
+        ctx->addClippingRect(root->x.computed, root->y.computed, root->width.computed, root->height.computed);
+
+    ctx->pushState();
+    renderer->setStateForItem(ctx, item);
+    ctx->transform(root->c2p);
+    sp_group_render(item, ctx);
+    ctx->popState();
+}
+
+static void sp_item_invoke_render(SPItem *item, CairoRenderContext *ctx)
+{
+    if (SP_IS_ROOT(item)) {
+        TRACE(("root\n"));
+        return sp_root_render(item, ctx);
+    } else if (SP_IS_GROUP(item)) {
+        TRACE(("group\n"));
+        return sp_group_render(item, ctx);
+    } else if (SP_IS_SHAPE(item)) {
+        TRACE(("shape\n"));
+        return sp_shape_render(item, ctx);
+    } else if (SP_IS_USE(item)) {
+        TRACE(("use begin---\n"));
+        sp_use_render(item, ctx);
+        TRACE(("---use end\n"));
+    } else if (SP_IS_SYMBOL(item)) {
+        TRACE(("symbol\n"));
+        return sp_symbol_render(item, ctx);
+    } else if (SP_IS_TEXT(item)) {
+        TRACE(("text\n"));
+        return sp_text_render(item, ctx);
+    } else if (SP_IS_FLOWTEXT(item)) {
+        TRACE(("flowtext\n"));
+        return sp_flowtext_render(item, ctx);
+    } else if (SP_IS_IMAGE(item)) {
+        TRACE(("image\n"));
+        return sp_image_render(item, ctx);
+    }
+}
+
+void
+CairoRenderer::setStateForItem(CairoRenderContext *ctx, SPItem const *item)
+{
+    SPStyle const *style = SP_OBJECT_STYLE(item);
+    ctx->setStateForStyle(style);
+    
+    CairoRenderState *state = ctx->getCurrentState();
+    state->clip_path = item->clip_ref->getObject();
+    state->mask = item->mask_ref->getObject();
+
+    // If parent_has_userspace is true the parent state's transform
+    // has to be used for the mask's/clippath's context.
+    // This is so because we use the image's/(flow)text's transform for positioning
+    // instead of explicitly specifying it and letting the renderer do the
+    // transformation before rendering the item.
+    if (SP_IS_TEXT(item) || SP_IS_FLOWTEXT(item) || SP_IS_IMAGE(item))
+        state->parent_has_userspace = TRUE;
+    TRACE(("set op: %f\n", state->opacity));
+}
+
+void
+CairoRenderer::renderItem(CairoRenderContext *ctx, SPItem *item)
+{
+    ctx->pushState();
+    setStateForItem(ctx, item);
+    
+    CairoRenderState *state = ctx->getCurrentState();
+    state->need_layer = ( state->mask || state->clip_path || state->opacity != 1.0 );
+
+    if (state->need_layer) {
+        state->merge_opacity = FALSE;
+        ctx->pushLayer();
+    }
+    ctx->transform(item->transform);
+    sp_item_invoke_render(item, ctx);
+
+    if (state->need_layer)
+        ctx->popLayer();
+
+    ctx->popState();
+}
+
+bool
+CairoRenderer::setupDocument(CairoRenderContext *ctx, SPDocument *doc)
+{
+    g_assert( ctx != NULL );
+
+    if (ctx->_vector_based_target) {
+        // width and height in pt
+        ctx->_width = sp_document_width(doc) * PT_PER_PX;
+        ctx->_height = sp_document_height(doc) * PT_PER_PX;
+    } else {
+        ctx->_width = sp_document_width(doc);
+        ctx->_height = sp_document_height(doc);
+    }
+
+    NRRect d;
+    bool pageBoundingBox = true;
+    if (pageBoundingBox) {
+        d.x0 = d.y0 = 0;
+        d.x1 = ceil(ctx->_width);
+        d.y1 = ceil(ctx->_height);
+    } else {
+        SPItem* doc_item = SP_ITEM(sp_document_root(doc));
+        sp_item_invoke_bbox(doc_item, &d, sp_item_i2r_affine(doc_item), TRUE);
+        if (ctx->_vector_based_target) {
+            // convert from px to pt
+            d.x0 *= PT_PER_PX;
+            d.x1 *= PT_PER_PX;
+            d.y0 *= PT_PER_PX;
+            d.y1 *= PT_PER_PX;
+        }
+    }
+    TRACE(("%f x %f\n", ctx->_width, ctx->_height));
+    
+    return ctx->setupSurface(d.x1-d.x0, d.y1-d.y0);
+}
+
+#include "macros.h" // SP_PRINT_*
+
+void
+CairoRenderer::applyClipPath(CairoRenderContext *ctx, SPClipPath const *cp)
+{
+    g_assert( ctx != NULL && ctx->_is_valid );
+        
+    if (cp == NULL)
+        return;
+    
+    CairoRenderContext::CairoRenderMode saved_mode = ctx->getRenderMode();
+    ctx->setRenderMode(CairoRenderContext::RENDER_MODE_CLIP);
+
+    NRMatrix saved_ctm;
+    if (cp->clipPathUnits == SP_CONTENT_UNITS_OBJECTBOUNDINGBOX) {
+        NRMatrix t;
+        //SP_PRINT_DRECT("clipd", cp->display->bbox);
+        NRRect clip_bbox(cp->display->bbox);
+        nr_matrix_set_scale(&t, clip_bbox.x1 - clip_bbox.x0, clip_bbox.y1 - clip_bbox.y0);
+        t.c[4] = clip_bbox.x0;
+        t.c[5] = clip_bbox.y0;
+        nr_matrix_multiply(&t, &t, &ctx->getCurrentState()->transform);
+        ctx->getTransform(&saved_ctm);
+        ctx->setTransform(&t);
+    }
+
+    TRACE(("BEGIN clip\n"));
+    SPObject *co = SP_OBJECT(cp);
+    for (SPObject *child = sp_object_first_child(co) ; child != NULL; child = SP_OBJECT_NEXT(child) ) {
+        if (SP_IS_ITEM(child)) {
+            SPItem *item = SP_ITEM(child);
+            renderItem(ctx, item);
+        }
+    }
+    TRACE(("END clip\n"));
+
+    // do clipping only if this was the first call to applyClipPath
+    if (ctx->getClipMode() == CairoRenderContext::CLIP_MODE_PATH
+        && saved_mode == CairoRenderContext::RENDER_MODE_NORMAL)
+        cairo_clip(ctx->_cr);
+
+    if (cp->clipPathUnits == SP_CONTENT_UNITS_OBJECTBOUNDINGBOX)
+        ctx->setTransform(&saved_ctm);
+
+    ctx->setRenderMode(saved_mode);
+}
+
+void
+CairoRenderer::applyMask(CairoRenderContext *ctx, SPMask const *mask)
+{
+    g_assert( ctx != NULL && ctx->_is_valid );
+        
+    if (mask == NULL)
+        return;
+
+    //SP_PRINT_DRECT("maskd", &mask->display->bbox);
+    NRRect mask_bbox(mask->display->bbox);
+    // TODO: should the bbox be transformed if maskUnits != userSpaceOnUse ?
+    if (mask->maskContentUnits == SP_CONTENT_UNITS_OBJECTBOUNDINGBOX) {
+        NRMatrix t;
+        nr_matrix_set_scale(&t, mask_bbox.x1 - mask_bbox.x0, mask_bbox.y1 - mask_bbox.y0);
+        t.c[4] = mask_bbox.x0;
+        t.c[5] = mask_bbox.y0;
+        nr_matrix_multiply(&t, &t, &ctx->getCurrentState()->transform);
+        ctx->setTransform(&t);
+    }
+
+    // clip mask contents
+    ctx->addClippingRect(mask_bbox.x0, mask_bbox.y0, mask_bbox.x1 - mask_bbox.x0, mask_bbox.y1 - mask_bbox.y0);
+
+    ctx->pushState();
+
+    TRACE(("BEGIN mask\n"));
+    SPObject *co = SP_OBJECT(mask);
+    for (SPObject *child = sp_object_first_child(co) ; child != NULL; child = SP_OBJECT_NEXT(child) ) {
+        if (SP_IS_ITEM(child)) {
+            SPItem *item = SP_ITEM(child);
+            renderItem(ctx, item);
+        }
+    }
+    TRACE(("END mask\n"));
+
+    ctx->popState();
+}
+
+void
+calculatePreserveAspectRatio(unsigned int aspect_align, unsigned int aspect_clip, double vp_width, double vp_height,
+                             double *x, double *y, double *width, double *height)
+{
+    if (aspect_align == SP_ASPECT_NONE)
+        return;
+        
+    double scalex, scaley, scale;
+    double new_width, new_height;
+    scalex = *width / vp_width;
+    scaley = *height / vp_height;
+    scale = (aspect_clip == SP_ASPECT_MEET) ? MIN(scalex, scaley) : MAX(scalex, scaley);
+    new_width = vp_width * scale;
+    new_height = vp_height * scale;
+    /* Now place viewbox to requested position */
+    switch (aspect_align) {
+        case SP_ASPECT_XMIN_YMIN:
+            break;
+        case SP_ASPECT_XMID_YMIN:
+            *x -= 0.5 * (new_width - *width);
+            break;
+        case SP_ASPECT_XMAX_YMIN:
+            *x -= 1.0 * (new_width - *width);
+            break;
+        case SP_ASPECT_XMIN_YMID:
+            *y -= 0.5 * (new_height - *height);
+            break;
+        case SP_ASPECT_XMID_YMID:
+            *x -= 0.5 * (new_width - *width);
+            *y -= 0.5 * (new_height - *height);
+            break;
+        case SP_ASPECT_XMAX_YMID:
+            *x -= 1.0 * (new_width - *width);
+            *y -= 0.5 * (new_height - *height);
+            break;
+        case SP_ASPECT_XMIN_YMAX:
+            *y -= 1.0 * (new_height - *height);
+            break;
+        case SP_ASPECT_XMID_YMAX:
+            *x -= 0.5 * (new_width - *width);
+            *y -= 1.0 * (new_height - *height);
+            break;
+        case SP_ASPECT_XMAX_YMAX:
+            *x -= 1.0 * (new_width - *width);
+            *y -= 1.0 * (new_height - *height);
+            break;
+        default:
+            break;
+    }
+    *width = new_width;
+    *height = new_height;
+}
+
+#include "clear-n_.h"
+
+}  /* namespace Internal */
+}  /* namespace Extension */
+}  /* namespace Inkscape */
+
+#undef TRACE
+
+/* End of GNU GPL code */
+
+#endif /* HAVE_CAIRO_PDF */
+
+
+/*
+  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 :