most of the 2.X->3.0 commit (up to rev 4299) except for gtk2_ardour/editor_canvas.cc; builds and runs and does a few specific things but expect it to be buggy for a while yet

git-svn-id: svn://localhost/ardour2/branches/3.0@4313 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 815 insertions, 0 deletions

diff --git a/libs/clearlooks-newer/cairo-support.c b/libs/clearlooks-newer/cairo-support.c
new file mode 100644
index 0000000000..dbe6fd3d34
--- /dev/null
+++ b/libs/clearlooks-newer/cairo-support.c
@@ -0,0 +1,815 @@
+#include <math.h>
+#include "general-support.h"
+#include "cairo-support.h"
+
+/***********************************************
+ * ge_hsb_from_color -
+ *  
+ *   Get HSB values from RGB values.
+ *
+ *   Modified from Smooth but originated in GTK+
+ ***********************************************/
+void
+ge_hsb_from_color (const CairoColor *color, 
+                        gdouble *hue, 
+                        gdouble *saturation,
+                        gdouble *brightness) 
+{
+	gdouble min, max, delta;
+	gdouble red, green, blue;
+
+	red = color->r;
+	green = color->g;
+	blue = color->b;
+  
+	if (red > green)
+	{
+		max = MAX(red, blue);
+		min = MIN(green, blue);
+	}
+	else
+	{
+		max = MAX(green, blue);
+		min = MIN(red, blue);
+	}
+  
+	*brightness = (max + min) / 2;
+ 	
+	if (fabs(max - min) < 0.0001)
+	{
+		*hue = 0;
+		*saturation = 0;
+	}	
+	else
+	{
+		if (*brightness <= 0.5)
+			*saturation = (max - min) / (max + min);
+		else
+			*saturation = (max - min) / (2 - max - min);
+       
+		delta = max -min;
+ 
+		if (red == max)
+			*hue = (green - blue) / delta;
+		else if (green == max)
+			*hue = 2 + (blue - red) / delta;
+		else if (blue == max)
+			*hue = 4 + (red - green) / delta;
+ 
+		*hue *= 60;
+		if (*hue < 0.0)
+			*hue += 360;
+	}
+}
+ 
+/***********************************************
+ * ge_color_from_hsb -
+ *  
+ *   Get RGB values from HSB values.
+ *
+ *   Modified from Smooth but originated in GTK+
+ ***********************************************/
+#define MODULA(number, divisor) (((gint)number % divisor) + (number - (gint)number))
+void
+ge_color_from_hsb (gdouble hue, 
+                        gdouble saturation,
+                        gdouble brightness, 
+                        CairoColor *color)
+{
+	gint i;
+	gdouble hue_shift[3], color_shift[3];
+	gdouble m1, m2, m3;
+
+	if (!color) return;
+  	  
+	if (brightness <= 0.5)
+		m2 = brightness * (1 + saturation);
+	else
+		m2 = brightness + saturation - brightness * saturation;
+ 
+	m1 = 2 * brightness - m2;
+ 
+	hue_shift[0] = hue + 120;
+	hue_shift[1] = hue;
+	hue_shift[2] = hue - 120;
+ 
+	color_shift[0] = color_shift[1] = color_shift[2] = brightness;	
+ 
+	i = (saturation == 0)?3:0;
+ 
+	for (; i < 3; i++)
+	{
+		m3 = hue_shift[i];
+ 
+		if (m3 > 360)
+			m3 = MODULA(m3, 360);
+		else if (m3 < 0)
+			m3 = 360 - MODULA(ABS(m3), 360);
+ 
+		if (m3 < 60)
+			color_shift[i] = m1 + (m2 - m1) * m3 / 60;
+		else if (m3 < 180)
+			color_shift[i] = m2;
+		else if (m3 < 240)
+			color_shift[i] = m1 + (m2 - m1) * (240 - m3) / 60;
+		else
+			color_shift[i] = m1;
+	}	
+ 
+	color->r = color_shift[0];
+	color->g = color_shift[1];
+	color->b = color_shift[2];	
+	color->a = 1.0;	
+}
+
+void
+ge_gdk_color_to_cairo (const GdkColor *c, CairoColor *cc)
+{
+	gdouble r, g, b;
+
+	g_return_if_fail (c && cc);
+
+	r = c->red / 65535.0;
+	g = c->green / 65535.0;
+	b = c->blue / 65535.0;
+
+	cc->r = r;
+	cc->g = g;
+	cc->b = b;
+	cc->a = 1.0;
+}
+
+void
+ge_cairo_color_to_gtk (const CairoColor *cc, GdkColor *c)
+{
+	gdouble r, g, b;
+
+	g_return_if_fail (c && cc);
+
+	r = cc->r * 65535.0;
+	g = cc->g * 65535.0;
+	b = cc->b * 65535.0;
+
+	c->red = r;
+	c->green = g;
+	c->blue = b;
+}
+
+void 
+ge_gtk_style_to_cairo_color_cube (GtkStyle * style, CairoColorCube *cube)
+{
+	int i;
+
+	g_return_if_fail (style && cube);
+
+	for (i = 0; i < 5; i++)
+	{ 
+		ge_gdk_color_to_cairo (&style->bg[i], &cube->bg[i]);
+		ge_gdk_color_to_cairo (&style->fg[i], &cube->fg[i]);
+
+		ge_gdk_color_to_cairo (&style->dark[i], &cube->dark[i]);
+		ge_gdk_color_to_cairo (&style->light[i], &cube->light[i]);
+		ge_gdk_color_to_cairo (&style->mid[i], &cube->mid[i]);
+
+		ge_gdk_color_to_cairo (&style->base[i], &cube->base[i]);
+		ge_gdk_color_to_cairo (&style->text[i], &cube->text[i]);
+		ge_gdk_color_to_cairo (&style->text_aa[i], &cube->text_aa[i]);
+    	}
+
+	cube->black.r = cube->black.g = cube->black.b = 0;
+	cube->black.a = 1;
+
+	cube->white.r = cube->white.g = cube->white.b = 1;
+	cube->white.a = 1;
+}
+
+void
+ge_shade_color(const CairoColor *base, gdouble shade_ratio, CairoColor *composite)
+{
+	gdouble hue = 0;
+	gdouble saturation = 0;
+	gdouble brightness = 0;
+ 
+	g_return_if_fail (base && composite);
+
+	ge_hsb_from_color (base, &hue, &saturation, &brightness);
+ 
+	brightness = MIN(brightness*shade_ratio, 1.0);
+	brightness = MAX(brightness, 0.0);
+  
+	saturation = MIN(saturation*shade_ratio, 1.0);
+	saturation = MAX(saturation, 0.0);
+  
+	ge_color_from_hsb (hue, saturation, brightness, composite);
+	composite->a = base->a;	
+}
+
+void
+ge_saturate_color (const CairoColor *base, gdouble saturate_level, CairoColor *composite)
+{
+	gdouble hue = 0;
+	gdouble saturation = 0;
+	gdouble brightness = 0;
+ 
+	g_return_if_fail (base && composite);
+
+	ge_hsb_from_color (base, &hue, &saturation, &brightness);
+
+	saturation = MIN(saturation*saturate_level, 1.0);
+	saturation = MAX(saturation, 0.0);
+
+	ge_color_from_hsb (hue, saturation, brightness, composite);
+	composite->a = base->a;	
+}
+
+void
+ge_mix_color (const CairoColor *color1, const CairoColor *color2, 
+              gdouble mix_factor, CairoColor *composite)
+{
+	g_return_if_fail (color1 && color2 && composite);
+
+	composite->r = color1->r * (1-mix_factor) + color2->r * mix_factor;
+	composite->g = color1->g * (1-mix_factor) + color2->g * mix_factor;
+	composite->b = color1->b * (1-mix_factor) + color2->b * mix_factor;
+	composite->a = 1.0;
+}
+
+cairo_t * 
+ge_gdk_drawable_to_cairo (GdkDrawable  *window, GdkRectangle *area)
+{
+	cairo_t *cr;
+
+	g_return_val_if_fail (window != NULL, NULL);
+
+	cr = (cairo_t*) gdk_cairo_create (window);
+	cairo_set_line_width (cr, 1.0);
+	cairo_set_line_cap (cr, CAIRO_LINE_CAP_SQUARE);
+	cairo_set_line_join (cr, CAIRO_LINE_JOIN_MITER);
+
+	if (area) 
+	{
+		cairo_rectangle (cr, area->x, area->y, area->width, area->height);
+		cairo_clip_preserve (cr);
+		cairo_new_path (cr);
+	}
+
+	return cr;
+}
+
+void 
+ge_cairo_set_color (cairo_t *cr, const CairoColor *color)
+{
+	g_return_if_fail (cr && color);
+
+	cairo_set_source_rgba (cr, color->r, color->g, color->b, color->a);	
+}
+
+void
+ge_cairo_set_gdk_color_with_alpha (cairo_t *cr, const GdkColor *color, gdouble alpha)
+{
+	g_return_if_fail (cr && color);
+
+	cairo_set_source_rgba (cr, color->red / 65535.0,
+	                           color->green / 65535.0,
+	                           color->blue / 65535.0,
+	                           alpha);
+}
+
+void 
+ge_cairo_pattern_add_color_stop_color (cairo_pattern_t *pattern, 
+						gfloat offset, 
+						const CairoColor *color)
+{
+	g_return_if_fail (pattern && color);
+
+	cairo_pattern_add_color_stop_rgba (pattern, offset, color->r, color->g, color->b, color->a);	
+}
+
+void
+ge_cairo_pattern_add_color_stop_shade(cairo_pattern_t *pattern, 
+						gdouble offset, 
+						const CairoColor *color, 
+						gdouble shade)
+{
+	CairoColor shaded;
+
+	g_return_if_fail (pattern && color && (shade >= 0) && (shade <= 3));
+
+	shaded = *color;
+
+	if (shade != 1)
+	{
+		ge_shade_color(color, shade, &shaded);
+	}
+
+	ge_cairo_pattern_add_color_stop_color(pattern, offset, &shaded);	
+}
+
+/* This function will draw a rounded corner at position x,y. If the radius
+ * is very small (or negative) it will instead just do a line_to.
+ * ge_cairo_rounded_corner assumes clockwise drawing. */
+void
+ge_cairo_rounded_corner (cairo_t      *cr,
+                         double        x,
+                         double        y,
+                         double        radius,
+                         CairoCorners  corner)
+{
+	if (radius < 0.0001)
+	{
+		cairo_line_to (cr, x, y);
+	}
+	else
+	{
+		switch (corner) {
+		case CR_CORNER_NONE:
+			cairo_line_to (cr, x, y);
+			break;
+		case CR_CORNER_TOPLEFT:
+			cairo_arc (cr, x + radius, y + radius, radius, G_PI, G_PI * 3/2);
+			break;
+		case CR_CORNER_TOPRIGHT:
+			cairo_arc (cr, x - radius, y + radius, radius, G_PI * 3/2, G_PI * 2);
+			break;
+		case CR_CORNER_BOTTOMRIGHT:
+			cairo_arc (cr, x - radius, y - radius, radius, 0, G_PI * 1/2);
+			break;
+		case CR_CORNER_BOTTOMLEFT:
+			cairo_arc (cr, x + radius, y - radius, radius, G_PI * 1/2, G_PI);
+			break;
+
+		default:
+			/* A bitfield and not a sane value ... */
+			g_assert_not_reached ();
+			cairo_line_to (cr, x, y);
+			return;
+		}
+	}
+}
+
+void
+ge_cairo_rounded_rectangle (cairo_t *cr,
+                                 double x, double y, double w, double h,
+                                 double radius, CairoCorners corners)
+{
+	g_return_if_fail (cr != NULL);
+
+	if (radius < 0.0001 || corners == CR_CORNER_NONE)
+	{
+		cairo_rectangle (cr, x, y, w, h);
+		return;
+	}
+#ifdef DEVELOPMENT
+	if ((corners == CR_CORNER_ALL) && (radius > w / 2.0 || radius > h / 2.0))
+		g_warning ("Radius is too large for width/height in ge_rounded_rectangle.\n");
+	else if (radius > w || radius > h) /* This isn't perfect. Assumes that only one corner is set. */
+		g_warning ("Radius is too large for width/height in ge_rounded_rectangle.\n");
+#endif
+
+	if (corners & CR_CORNER_TOPLEFT)
+		cairo_move_to (cr, x+radius, y);
+	else
+		cairo_move_to (cr, x, y);
+	
+	if (corners & CR_CORNER_TOPRIGHT)
+		cairo_arc (cr, x+w-radius, y+radius, radius, G_PI * 1.5, G_PI * 2);
+	else
+		cairo_line_to (cr, x+w, y);
+	
+	if (corners & CR_CORNER_BOTTOMRIGHT)
+		cairo_arc (cr, x+w-radius, y+h-radius, radius, 0, G_PI * 0.5);
+	else
+		cairo_line_to (cr, x+w, y+h);
+	
+	if (corners & CR_CORNER_BOTTOMLEFT)
+		cairo_arc (cr, x+radius,   y+h-radius, radius, G_PI * 0.5, G_PI);
+	else
+		cairo_line_to (cr, x, y+h);
+	
+	if (corners & CR_CORNER_TOPLEFT)
+		cairo_arc (cr, x+radius,   y+radius,   radius, G_PI, G_PI * 1.5);
+	else
+		cairo_line_to (cr, x, y);
+}
+
+
+/* ge_cairo_stroke_rectangle.
+ *
+ *  A simple function to stroke the rectangle { x, y, w, h}.
+ *  (This function only exists because of a cairo performance bug that
+ *    has been fixed and it may be a good idea to get rid of it again.)
+ */
+void
+ge_cairo_stroke_rectangle (cairo_t *cr, double x, double y, double w, double h)
+{
+	cairo_rectangle (cr, x, y, w, h);
+	cairo_stroke (cr);
+}
+
+/***********************************************
+ * ge_cairo_simple_border -
+ *  
+ *   A simple routine to draw thin squared
+ *   borders with a topleft and bottomright color.
+ *    
+ *   It originated in Smooth-Engine.
+ ***********************************************/
+void
+ge_cairo_simple_border (cairo_t *cr,
+				const CairoColor * tl, const CairoColor * br,
+				gint x,	gint y, gint width, gint height, 
+				gboolean topleft_overlap)
+{
+	gboolean solid_color;
+
+	g_return_if_fail (cr != NULL);
+	g_return_if_fail (tl != NULL);
+	g_return_if_fail (br != NULL);
+	
+
+	solid_color = (tl == br) || ((tl->r == br->r) && (tl->g == br->g) && (tl->b == br->b) && (tl->a == br->a));
+
+	topleft_overlap &= !solid_color;
+
+	cairo_save(cr);
+
+	cairo_set_line_width (cr, 1);
+
+	if (topleft_overlap)
+	{
+		ge_cairo_set_color(cr, br);	
+
+		cairo_move_to(cr, x + 0.5, y + height - 0.5);
+		cairo_line_to(cr, x + width - 0.5, y + height - 0.5);
+		cairo_line_to(cr, x + width - 0.5, y + 0.5);
+		
+		cairo_stroke (cr);
+	}
+ 
+	ge_cairo_set_color(cr, tl);	
+
+	cairo_move_to(cr, x + 0.5, y + height - 0.5);
+	cairo_line_to(cr, x + 0.5, y + 0.5);
+	cairo_line_to(cr, x + width - 0.5, y + 0.5);
+
+	if (!topleft_overlap)
+	{
+		if (!solid_color)
+		{
+			cairo_stroke(cr);
+			ge_cairo_set_color(cr, br);	
+		}
+
+		cairo_move_to(cr, x + 0.5, y + height - 0.5);
+		cairo_line_to(cr, x + width - 0.5, y + height - 0.5);
+		cairo_line_to(cr, x + width - 0.5, y + 0.5);
+	}
+
+	cairo_stroke(cr);
+
+	cairo_restore(cr);
+}
+
+void ge_cairo_polygon (cairo_t *cr,
+				const CairoColor *color,
+				GdkPoint *points,
+				gint npoints)
+{
+	int i = 0;
+
+	cairo_save(cr);
+
+	ge_cairo_set_color(cr, color);	
+	cairo_move_to(cr, points[0].x, points[0].y);
+
+	for (i = 1; i < npoints; i++)
+	{
+		if (!((points[i].x == points[i + 1].x) &&
+		    (points[i].y == points[i + 1].y))) 
+		{
+			cairo_line_to(cr, points[i].x, points[i].y);
+		}
+	}
+	
+	if ((points[npoints-1].x != points[0].y) ||
+		(points[npoints-1].y != points[0].y))
+	{
+		cairo_line_to(cr, points[0].x, points[0].y);
+	}
+
+	cairo_fill(cr);
+
+	cairo_restore(cr);
+}
+
+void ge_cairo_line (cairo_t *cr,
+			const CairoColor *color,
+			gint x1,
+			gint y1,
+			gint x2,
+			gint y2)
+{ 
+	cairo_save(cr);
+
+	ge_cairo_set_color(cr, color);	
+	cairo_set_line_width (cr, 1);
+
+	cairo_move_to(cr, x1 + 0.5, y1 + 0.5);
+	cairo_line_to(cr, x2 + 0.5, y2 + 0.5);
+
+	cairo_stroke(cr);
+
+	cairo_restore(cr);
+}
+
+void
+ge_cairo_mirror (cairo_t     *cr,
+                 CairoMirror  mirror,
+                 gint        *x,
+                 gint        *y,
+                 gint        *width,
+                 gint        *height)
+{
+	cairo_matrix_t matrix;
+	
+	cairo_matrix_init_identity (&matrix);
+	
+	cairo_translate (cr, *x, *y);
+	*x = 0;
+	*y = 0;
+	
+	if (mirror & CR_MIRROR_HORIZONTAL)
+	{
+		cairo_matrix_scale (&matrix, -1, 1);
+		*x = -*width;
+	}
+	if (mirror & CR_MIRROR_VERTICAL)
+	{
+		cairo_matrix_scale (&matrix, 1, -1);
+		*y = -*height;
+	}
+
+	cairo_transform (cr, &matrix);
+}
+
+void
+ge_cairo_exchange_axis (cairo_t  *cr,
+                        gint     *x,
+                        gint     *y,
+                        gint     *width,
+                        gint     *height)
+{
+	gint tmp;
+	cairo_matrix_t matrix;
+
+	cairo_translate (cr, *x, *y);
+	cairo_matrix_init (&matrix, 0, 1, 1, 0, 0, 0);
+
+	cairo_transform (cr, &matrix);
+	
+	/* swap width/height */
+	tmp = *width;
+	*x = 0;
+	*y = 0;
+	*width = *height;
+	*height = tmp;
+}
+
+
+/***********************************************
+ * ge_cairo_pattern_fill -
+ *  
+ *   Fill an area with some pattern
+ *   Scaling or tiling if needed
+ ***********************************************/
+void 
+ge_cairo_pattern_fill(cairo_t *canvas,
+			CairoPattern *pattern,
+			gint x,
+			gint y,
+			gint width,
+			gint height)
+{
+	cairo_matrix_t original_matrix, current_matrix;
+
+	if (pattern->operator == CAIRO_OPERATOR_DEST)
+	{
+		return;
+	}
+
+	cairo_pattern_get_matrix(pattern->handle, &original_matrix);
+	current_matrix = original_matrix;
+
+	if (pattern->scale != GE_DIRECTION_NONE)
+	{
+		gdouble scale_x = 1.0;
+		gdouble scale_y = 1.0;
+
+		if ((pattern->scale == GE_DIRECTION_VERTICAL) || (pattern->scale == GE_DIRECTION_BOTH))
+		{
+			scale_x = 1.0/width;
+		}
+
+		if ((pattern->scale == GE_DIRECTION_HORIZONTAL) || (pattern->scale == GE_DIRECTION_BOTH))
+		{
+			scale_y = 1.0/height;
+		}
+
+		cairo_matrix_scale(&current_matrix, scale_x, scale_y);
+	}
+
+	if (pattern->translate != GE_DIRECTION_NONE)
+	{
+		gdouble translate_x = 0;
+		gdouble translate_y = 0;
+
+		if ((pattern->translate == GE_DIRECTION_VERTICAL) || (pattern->translate == GE_DIRECTION_BOTH))
+		{
+			translate_x = 0.0-x;
+		}
+
+		if ((pattern->translate == GE_DIRECTION_HORIZONTAL) || (pattern->translate == GE_DIRECTION_BOTH))
+		{
+			translate_y = 0.0-y;
+		}
+
+		cairo_matrix_translate(&current_matrix, translate_x, translate_y);
+	}
+
+	cairo_pattern_set_matrix(pattern->handle, &current_matrix);
+
+	cairo_save(canvas);
+
+	cairo_set_source(canvas, pattern->handle);
+        cairo_set_operator(canvas, pattern->operator);
+	cairo_rectangle(canvas, x, y, width, height);
+
+	cairo_fill (canvas);
+
+	cairo_restore(canvas);
+
+	cairo_pattern_set_matrix(pattern->handle, &original_matrix);
+}
+
+/***********************************************
+ * ge_cairo_color_pattern -
+ *  
+ *   Create A Solid Color Pattern
+ ***********************************************/
+CairoPattern*
+ge_cairo_color_pattern(CairoColor *base)
+{	
+	CairoPattern * result = g_new0(CairoPattern, 1);
+
+	#if  ((CAIRO_VERSION_MAJOR < 1) || ((CAIRO_VERSION_MAJOR == 1) && (CAIRO_VERSION_MINOR < 2)))
+		result->type = CAIRO_PATTERN_TYPE_SOLID;
+	#endif
+
+	result->scale = GE_DIRECTION_NONE;
+	result->translate = GE_DIRECTION_NONE;
+
+	result->handle = cairo_pattern_create_rgba(base->r, 
+							base->g, 
+							base->b, 
+							base->a);
+
+	result->operator = CAIRO_OPERATOR_SOURCE;
+	
+	return result;
+}
+
+/***********************************************
+ * ge_cairo_pixbuf_pattern -
+ *  
+ *   Create A Tiled Pixbuf Pattern
+ ***********************************************/
+CairoPattern*
+ge_cairo_pixbuf_pattern(GdkPixbuf *pixbuf)
+{	
+	CairoPattern * result = g_new0(CairoPattern, 1);
+
+	cairo_t *canvas;
+	cairo_surface_t * surface;
+	gint width, height;
+
+	#if  ((CAIRO_VERSION_MAJOR < 1) || ((CAIRO_VERSION_MAJOR == 1) && (CAIRO_VERSION_MINOR < 2)))
+		result->type = CAIRO_PATTERN_TYPE_SURFACE;
+	#endif
+
+	result->scale = GE_DIRECTION_NONE;
+	result->translate = GE_DIRECTION_BOTH;
+
+	width = gdk_pixbuf_get_width(pixbuf);
+	height = gdk_pixbuf_get_height(pixbuf);
+	
+	surface = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height);
+
+	canvas = cairo_create(surface);
+
+	gdk_cairo_set_source_pixbuf (canvas, pixbuf, 0, 0);
+	cairo_rectangle (canvas, 0, 0, width, height);
+	cairo_fill (canvas);
+	cairo_destroy(canvas);
+
+	result->handle = cairo_pattern_create_for_surface (surface);
+	cairo_surface_destroy(surface);
+
+	cairo_pattern_set_extend (result->handle, CAIRO_EXTEND_REPEAT);
+
+	result->operator = CAIRO_OPERATOR_SOURCE;
+
+	return result;
+}
+
+/***********************************************
+ * ge_cairo_pixmap_pattern -
+ *  
+ *   Create A Tiled Pixmap Pattern
+ ***********************************************/
+CairoPattern*
+ge_cairo_pixmap_pattern(GdkPixmap *pixmap)
+{	
+	CairoPattern * result = NULL;
+
+	GdkPixbuf * pixbuf;
+	gint width, height;
+
+	gdk_drawable_get_size (GDK_DRAWABLE (pixmap), &width, &height);
+
+	pixbuf = gdk_pixbuf_get_from_drawable(NULL, GDK_DRAWABLE (pixmap), 
+				gdk_drawable_get_colormap(GDK_DRAWABLE (pixmap)), 
+				0, 0, 0, 0, width, height);
+
+	result = ge_cairo_pixbuf_pattern(pixbuf);
+	
+	g_object_unref (pixbuf);
+
+	return result;
+}
+
+/***********************************************
+ * ge_cairo_linear_shade_gradient_pattern - 
+ *  
+ *   Create A Linear Shade Gradient Pattern
+ *   Aka Smooth Shade Gradient, from/to gradient
+ *   With End points defined as shades of the
+ *   base color
+ ***********************************************/
+CairoPattern *
+ge_cairo_linear_shade_gradient_pattern(CairoColor *base, 
+						gdouble shade1, 
+						gdouble shade2, 
+						gboolean vertical)
+{
+	CairoPattern * result = g_new0(CairoPattern, 1);
+	
+	#if  ((CAIRO_VERSION_MAJOR < 1) || ((CAIRO_VERSION_MAJOR == 1) && (CAIRO_VERSION_MINOR < 2)))
+		result->type = CAIRO_PATTERN_TYPE_LINEAR;
+	#endif
+
+	if (vertical)
+	{
+		result->scale = GE_DIRECTION_VERTICAL;
+
+		result->handle = cairo_pattern_create_linear(0, 0, 1, 0);
+	}
+	else
+	{
+		result->scale = GE_DIRECTION_HORIZONTAL;
+
+		result->handle = cairo_pattern_create_linear(0, 0, 0, 1);
+	}
+
+	result->translate = GE_DIRECTION_BOTH;
+	result->operator = CAIRO_OPERATOR_SOURCE;
+
+	ge_cairo_pattern_add_color_stop_shade(result->handle, 0, base, shade1);
+	ge_cairo_pattern_add_color_stop_shade(result->handle, 1, base, shade2);
+
+	return result;
+}
+
+void
+ge_cairo_pattern_destroy(CairoPattern *pattern)
+{
+	if (pattern)
+	{
+		if (pattern->handle)
+			cairo_pattern_destroy(pattern->handle);
+			
+		g_free(pattern);
+	}
+}
+
+/* The following function will be called by GTK+ when the module
+ * is loaded and checks to see if we are compatible with the
+ * version of GTK+ that loads us.
+ */
+GE_EXPORT const gchar* g_module_check_init (GModule *module);
+const gchar*
+g_module_check_init (GModule *module)
+{
+  return gtk_check_version (GTK_MAJOR_VERSION,
+			    GTK_MINOR_VERSION,
+			    GTK_MICRO_VERSION - GTK_INTERFACE_AGE);
+}