Add support for exporting canvas as PDF or PS.

git-svn-id: http://svn.drobilla.net/lad/trunk/ganv@5543 a436a847-0d15-0410-975c-d299462d15a1

9 files changed, 124 insertions, 62 deletions

diff --git a/NEWS b/NEWS
index e6ea402..60df0eb 100644
--- a/NEWS
+++ b/NEWS
@@ -1,11 +1,13 @@
-ganv (1.4.3) unstable;
+ganv (1.5.0) unstable;
 
   * Fix positioning of embedded widgets when changing layout.
   * Fix unexpected node jumping when dragging new connections.
+  * Add support for PDF and PS export.
+  * Improve text rendering at high zoom.
   * Fix compilation with --no-fdgl (patch from Vlad Glagolev).
   * Fix crash when destroying canvas.
 
- -- David Robillard <d@drobilla.net>  Thu, 05 Feb 2015 18:32:13 -0500
+ -- David Robillard <d@drobilla.net>  Sun, 08 Feb 2015 08:32:08 -0500
 
 ganv (1.4.2) stable;
 
diff --git a/ganv/Canvas.hpp b/ganv/Canvas.hpp
index 88211d4..4a83de2 100644
--- a/ganv/Canvas.hpp
+++ b/ganv/Canvas.hpp
@@ -84,6 +84,7 @@ public:
 	void  remove_edge(Edge* edge);
 	
 	METHOD0(ganv_canvas, arrange);
+	METHODRET2(ganv_canvas, int, export_image, const char*, filename, bool, draw_background);
 	METHOD1(ganv_canvas, export_dot, const char*, filename);
 	METHODRET0(ganv_canvas, gboolean, supports_sprung_layout);
 	METHODRET1(ganv_canvas, gboolean, set_sprung_layout, gboolean, sprung_layout);
diff --git a/ganv/canvas.h b/ganv/canvas.h
index 83e3f8a..e923f65 100644
--- a/ganv/canvas.h
+++ b/ganv/canvas.h
@@ -378,6 +378,19 @@ void
 ganv_canvas_arrange(GanvCanvas* canvas);
 
 /**
+ * ganv_canvas_export_image:
+ *
+ * Draw the canvas to an image file.  The file type is determined by extension,
+ * currently supported: pdf, ps, svg, dot.
+ *
+ * Returns: 0 on success.
+ */
+int
+ganv_canvas_export_image(GanvCanvas* canvas,
+                         const char* filename,
+                         gboolean    draw_background);
+
+/**
  * ganv_canvas_export_dot:
  *
  * Write a Graphviz DOT description of the canvas to a file.
diff --git a/ganv/wrap.hpp b/ganv/wrap.hpp
index f4f2e9c..f907dea 100644
--- a/ganv/wrap.hpp
+++ b/ganv/wrap.hpp
@@ -76,6 +76,11 @@ private: \
 		return prefix##_##name(gobj(), a1); \
 	}
 
+#define METHODRET2(prefix, ret, name, t1, a1, t2, a2) \
+	virtual ret name(t1 a1, t2 a2) { \
+		return prefix##_##name(gobj(), a1, a2); \
+	}
+
 #define METHODRETWRAP0(prefix, ret, name) \
 	virtual ret name() const { \
 		if (gobj()) { \
diff --git a/src/Canvas.cpp b/src/Canvas.cpp
index 02bf4f6..c3ed2f6 100644
--- a/src/Canvas.cpp
+++ b/src/Canvas.cpp
@@ -2586,6 +2586,64 @@ ganv_canvas_arrange(GanvCanvas* canvas)
 #endif
 }
 
+int
+ganv_canvas_export_image(GanvCanvas* canvas,
+                         const char* filename,
+                         gboolean    draw_background)
+{
+	const char* ext = strrchr(filename, '.');
+	if (!ext) {
+		return 1;
+	} else if (!strcmp(ext, ".dot")) {
+		ganv_canvas_export_dot(canvas, filename);
+		return 0;
+	}
+
+	cairo_surface_t* rec_surface = cairo_recording_surface_create(
+		CAIRO_CONTENT_COLOR_ALPHA, NULL);
+
+	// Draw to recording surface
+	cairo_t* cr = cairo_create(rec_surface);
+	(*GANV_ITEM_GET_CLASS(canvas->impl->root)->draw)(
+		canvas->impl->root, cr,
+		0, 0, canvas->impl->width, canvas->impl->height);
+	cairo_destroy(cr);	
+
+	// Get draw extent
+	double x, y, w, h;
+	cairo_recording_surface_ink_extents(rec_surface, &x, &y, &w, &h);
+
+	// Create image surface with the appropriate size
+	const double     pad   = GANV_CANVAS_PAD;
+	const double     img_w = w + pad * 2;
+	const double     img_h = h + pad * 2;
+	cairo_surface_t* img   = NULL;
+	if (!strcmp(ext, ".svg")) {
+		img = cairo_svg_surface_create(filename, img_w, img_h);
+	} else if (!strcmp(ext, ".pdf")) {
+		img = cairo_pdf_surface_create(filename, img_w, img_h);
+	} else if (!strcmp(ext, ".ps")) {
+		img = cairo_ps_surface_create(filename, img_w, img_h);
+	} else {
+		cairo_surface_destroy(rec_surface);
+		return 1;
+	}	
+
+	// Draw recording to image surface
+	cr = cairo_create(img);
+	if (draw_background) {
+		cairo_set_source_rgba(cr, 0, 0, 0, 1.0);
+		cairo_rectangle(cr, 0, 0, w + 2 * pad, h + 2 * pad);
+		cairo_fill(cr);
+	}
+	cairo_set_source_surface(cr, rec_surface, -x + pad, -y + pad);
+	cairo_paint(cr);
+	cairo_destroy(cr);	
+	cairo_surface_destroy(rec_surface);
+	cairo_surface_destroy(img);
+	return 0;
+}
+
 void
 ganv_canvas_export_dot(GanvCanvas* canvas, const char* filename)
 {
@@ -3590,6 +3648,13 @@ ganv_canvas_paint_rect(GanvCanvas* canvas, gint x0, gint y0, gint x1, gint y1)
 		double wx1, wy1, ww, wh;
 		ganv_canvas_c2w(canvas, draw_x1, draw_y1, &wx1, &wy1);
 		ganv_canvas_c2w(canvas, draw_width, draw_height, &ww, &wh);
+
+		// Draw background
+		cairo_set_source_rgba(cr, 0, 0, 0, 1.0);
+		cairo_rectangle(cr, wx1, wy1, ww, wh);
+		cairo_fill(cr);
+
+		// Draw root group
 		(*GANV_ITEM_GET_CLASS(canvas->impl->root)->draw)(
 			canvas->impl->root, cr,
 			wx1, wy1, ww, wh);
diff --git a/src/ganv-private.h b/src/ganv-private.h
index 8f32480..2fc6c00 100644
--- a/src/ganv-private.h
+++ b/src/ganv-private.h
@@ -237,7 +237,7 @@ typedef struct
 
 struct _GanvTextImpl
 {
-	cairo_surface_t* surface;
+	PangoLayout*     layout;
 	char*            text;
 	GanvTextCoords   coords;
 	GanvTextCoords   old_coords;
diff --git a/src/group.c b/src/group.c
index 20ef354..e867cef 100644
--- a/src/group.c
+++ b/src/group.c
@@ -203,11 +203,6 @@ ganv_group_draw(GanvItem* item,
 {
 	GanvGroup* group = GANV_GROUP(item);
 
-	// Draw background
-	cairo_set_source_rgba(cr, 0, 0, 0, 1.0);
-	cairo_rectangle(cr, cx, cy, cw, ch);
-	cairo_fill(cr);
-
 	// TODO: Layered drawing
 
 	for (GList* list = group->impl->item_list; list; list = list->next) {
diff --git a/src/text.c b/src/text.c
index 39df696..6dda2e1 100644
--- a/src/text.c
+++ b/src/text.c
@@ -55,7 +55,7 @@ ganv_text_init(GanvText* text)
 	impl->coords.height = 1.0;
 	impl->old_coords = impl->coords;
 
-	impl->surface      = NULL;
+	impl->layout       = NULL;
 	impl->text         = NULL;
 	impl->color        = 0xFFFFFFFF;
 	impl->needs_layout = FALSE;
@@ -75,9 +75,9 @@ ganv_text_destroy(GtkObject* object)
 		impl->text = NULL;
 	}
 
-	if (impl->surface) {
-		cairo_surface_destroy(impl->surface);
-		impl->surface = NULL;
+	if (impl->layout) {
+		g_object_unref(impl->layout);
+		impl->layout = NULL;
 	}
 
 	if (GTK_OBJECT_CLASS(parent_class)->destroy) {
@@ -88,57 +88,36 @@ ganv_text_destroy(GtkObject* object)
 void
 ganv_text_layout(GanvText* text)
 {
-	GanvTextImpl* impl      = text->impl;
-	GanvItem*     item      = GANV_ITEM(text);
-	GanvCanvas*   canvas    = ganv_item_get_canvas(item);
-	GtkWidget*    widget    = GTK_WIDGET(canvas);
-	double        font_size = ganv_canvas_get_font_size(canvas);
-	guint         color     = 0xFFFFFFFF;
-
-	GtkStyle*             style   = gtk_rc_get_style(widget);
-	PangoFontDescription* font    = pango_font_description_copy(style->font_desc);
-	PangoLayout*          layout  = gtk_widget_create_pango_layout(widget, impl->text);
-	PangoContext*         context = pango_layout_get_context(layout);
-	cairo_font_options_t* options = cairo_font_options_copy(
-		pango_cairo_context_get_font_options(context));
-
-	pango_font_description_set_size(font, font_size * (double)PANGO_SCALE);
-	pango_layout_set_font_description(layout, font);
-
-	if (cairo_font_options_get_antialias(options) == CAIRO_ANTIALIAS_SUBPIXEL) {
-		cairo_font_options_set_antialias(options, CAIRO_ANTIALIAS_GRAY);
+	GanvTextImpl* impl   = text->impl;
+	GanvItem*     item   = GANV_ITEM(text);
+	GanvCanvas*   canvas = ganv_item_get_canvas(item);
+	GtkWidget*    widget = GTK_WIDGET(canvas);
+	double        points = ganv_canvas_get_font_size(canvas);
+	GtkStyle*     style  = gtk_rc_get_style(widget);
+
+	if (impl->layout) {
+		g_object_unref(impl->layout);
 	}
+	impl->layout = gtk_widget_create_pango_layout(widget, impl->text);
 
-	pango_cairo_context_set_font_options(context, options);
-	cairo_font_options_destroy(options);
+	PangoFontDescription* font = pango_font_description_copy(style->font_desc);
+	PangoContext*         ctx  = pango_layout_get_context(impl->layout);
+	cairo_font_options_t* opt  = cairo_font_options_copy(
+		pango_cairo_context_get_font_options(ctx));
+
+	pango_font_description_set_size(font, points * (double)PANGO_SCALE);
+	pango_layout_set_font_description(impl->layout, font);
+	pango_cairo_context_set_font_options(ctx, opt);
+	cairo_font_options_destroy(opt);
+	pango_font_description_free(font);
 
 	int width, height;
-	pango_layout_get_pixel_size(layout, &width, &height);
+	pango_layout_get_pixel_size(impl->layout, &width, &height);
 
-	impl->coords.width = width;
+	impl->coords.width  = width;
 	impl->coords.height = height;
+	impl->needs_layout  = FALSE;
 
-	if (impl->surface) {
-		cairo_surface_destroy(impl->surface);
-	}
-
-	impl->surface = cairo_image_surface_create(
-		CAIRO_FORMAT_ARGB32, width, height);
-
-	cairo_t* cr = cairo_create(impl->surface);
-
-	double r, g, b, a;
-	color_to_rgba(color, &r, &g, &b, &a);
-
-	cairo_set_source_rgba(cr, r, g, b, a);
-	cairo_move_to(cr, 0, 0);
-	pango_cairo_show_layout(cr, layout);
-
-	cairo_destroy(cr);
-	g_object_unref(layout);
-	pango_font_description_free(font);
-
-	impl->needs_layout = FALSE;
 	ganv_item_request_update(GANV_ITEM(text));
 }
 
@@ -293,12 +272,14 @@ ganv_text_draw(GanvItem* item,
 		ganv_text_layout(text);
 	}
 
-	// Round to the nearest pixel so text isn't blurry
-	wx = lrint(wx);
-	wy = lrint(wy);
+	guint color = 0xFFFFFFFF;
 
-	cairo_set_source_surface(cr, impl->surface, wx, wy);
-	cairo_paint(cr);
+	double r, g, b, a;
+	color_to_rgba(color, &r, &g, &b, &a);
+
+	cairo_set_source_rgba(cr, r, g, b, a);
+	cairo_move_to(cr, wx, wy);
+	pango_cairo_show_layout(cr, impl->layout);
 }
 
 static void
diff --git a/wscript b/wscript
index 894bbee..d1c0686 100644
--- a/wscript
+++ b/wscript
@@ -8,7 +8,7 @@ import waflib.extras.autowaf as autowaf
 # major increment <=> incompatible changes
 # minor increment <=> compatible changes (additions)
 # micro increment <=> no interface changes
-GANV_VERSION       = '1.4.3'
+GANV_VERSION       = '1.5.0'
 GANV_MAJOR_VERSION = '1'
 
 # Mandatory waf variables