[murrine] Moved expander drawing code in murrine_draw.c. Support styles, only arrow available for now

[Andrea Cimitan <acimitan src gnome org>]

commit 1b1ffe7babb4a115a611228a697fc4d159f20b60
Author: Andrea Cimitan <andrea cimitan gmail com>
Date:   Tue May 25 19:25:50 2010 +0100

    Moved expander drawing code in murrine_draw.c. Support styles, only arrow available for now

 src/murrine_draw.c  |  134 ++++++++++++++++++++++++++++++++++++++++++++++++--
 src/murrine_style.c |   53 ++++----------------
 src/murrine_types.h |   15 ++++++
 3 files changed, 153 insertions(+), 49 deletions(-)
---
diff --git a/src/murrine_draw.c b/src/murrine_draw.c
index f8e8c0b..b2cea6c 100644
--- a/src/murrine_draw.c
+++ b/src/murrine_draw.c
@@ -2153,7 +2153,7 @@ murrine_draw_normal_arrow_new (cairo_t *cr,
 {
 	int arrow_width = width;
 	int arrow_height = height;
-	cairo_pattern_t *pattern;
+	cairo_pattern_t *pat;
 
 	cairo_save (cr);
 
@@ -2163,12 +2163,12 @@ murrine_draw_normal_arrow_new (cairo_t *cr,
 	cairo_line_to (cr, arrow_width/2, -arrow_height/2);
 	cairo_close_path (cr);
 
-	pattern = cairo_pattern_create_linear (0, -arrow_height/2, 0, arrow_height/2);
-	cairo_pattern_add_color_stop_rgba (pattern, 0.0, color->r, color->g, color->b, 0.6);
-	cairo_pattern_add_color_stop_rgba (pattern, 1.0, color->r, color->g, color->b, 0.8);
-	cairo_set_source (cr, pattern);
+	pat = cairo_pattern_create_linear (0, -arrow_height/2, 0, arrow_height/2);
+	murrine_pattern_add_color_stop_rgba (pat, 0.0, color, 0.6);
+	murrine_pattern_add_color_stop_rgba (pat, 1.0, color, 0.8);
+	cairo_set_source (cr, pat);
 	cairo_fill_preserve (cr);
-	cairo_pattern_destroy (pattern);
+	cairo_pattern_destroy (pat);
 
 	murrine_set_color_rgb (cr, color);
 	cairo_stroke (cr);
@@ -2647,6 +2647,127 @@ murrine_draw_classic_focus (cairo_t *cr,
 	cairo_stroke (cr);
 }
 
+static void
+murrine_draw_expander_arrow (cairo_t *cr,
+	                     const MurrineColors    *colors,
+	                     const WidgetParameters *widget,
+	                     const ExpanderParameters *expander,
+	                     int x, int y, int width, int height)
+{
+	MurrineRGB color;
+	cairo_pattern_t *pat;
+
+	int diameter;
+	double vertical_overshoot;
+	double radius;
+	double interp; /* interpolation factor for center position */
+	double x_double_horz, y_double_horz;
+	double x_double_vert, y_double_vert;
+	double x_double, y_double;
+	gint degrees = 0;
+	gint line_width = 1;
+
+	switch (expander->expander_style)
+	{
+		case GTK_EXPANDER_COLLAPSED:
+			degrees = (expander->text_direction == GTK_TEXT_DIR_RTL) ? 180 : 0;
+			interp = 0.0;
+			break;
+		case GTK_EXPANDER_SEMI_COLLAPSED:
+			degrees = (expander->text_direction == GTK_TEXT_DIR_RTL) ? 150 : 30;
+			interp = 0.25;
+			break;
+		case GTK_EXPANDER_SEMI_EXPANDED:
+			degrees = (expander->text_direction == GTK_TEXT_DIR_RTL) ? 120 : 60;
+			interp = 0.75;
+			break;
+		case GTK_EXPANDER_EXPANDED:
+			degrees = 90;
+			interp = 1.0;
+			break;
+		default:
+			g_assert_not_reached ();
+	}
+
+	/* Compute distance that the stroke extends beyonds the end
+	* of the triangle we draw.
+	*/
+	vertical_overshoot = line_width / 2.0 * (1. / tan (G_PI / 8));
+
+	/* For odd line widths, we end the vertical line of the triangle
+	* at a half pixel, so we round differently.
+	*/
+	if (line_width % 2 == 1)
+		vertical_overshoot = ceil (0.5 + vertical_overshoot) - 0.5;
+	else
+		vertical_overshoot = ceil (vertical_overshoot);
+
+	/* Adjust the size of the triangle we draw so that the entire stroke fits
+	*/
+	diameter = MAX (3, expander->size - 2 * vertical_overshoot);
+
+	/* If the line width is odd, we want the diameter to be even,
+	* and vice versa, so force the sum to be odd. This relationship
+	* makes the point of the triangle look right.
+	*/
+	diameter -= (1 - (diameter + line_width) % 2);
+
+	radius = diameter / 2. + 4;
+
+	/* Adjust the center so that the stroke is properly aligned with
+	* the pixel grid. The center adjustment is different for the
+	* horizontal and vertical orientations. For intermediate positions
+	* we interpolate between the two.
+	*/
+	x_double_vert = floor (x - (radius + line_width) / 2.) + (radius + line_width) / 2. + ceil (radius / 8.0);
+	y_double_vert = y - 0.5;
+
+	x_double_horz = x - 0.5 + ceil (radius / 8.0);
+	y_double_horz = floor (y - (radius + line_width) / 2.) + (radius + line_width) / 2.;
+
+	x_double = x_double_vert * (1 - interp) + x_double_horz * interp;
+	y_double = y_double_vert * (1 - interp) + y_double_horz * interp;
+
+	cairo_translate (cr, x_double, y_double);
+	cairo_rotate (cr, degrees * G_PI / 180);
+
+	cairo_move_to (cr, -radius / 2.0, -radius / 2.0);
+	cairo_line_to (cr,  radius / 2.0,  0);
+	cairo_line_to (cr, -radius / 2.0,  radius / 2.0);
+	cairo_close_path (cr);
+	
+	if (expander->in_treeview)
+		color = colors->text[widget->state_type];
+	else
+		color = colors->fg[widget->state_type];
+
+	pat = cairo_pattern_create_linear (-radius/2.0, 0, radius/2.0, 0);
+	murrine_pattern_add_color_stop_rgba (pat, 0.0, &color, 0.6);
+	murrine_pattern_add_color_stop_rgba (pat, 1.0, &color, 0.8);
+	cairo_set_source (cr, pat);
+	cairo_fill_preserve (cr);
+	cairo_pattern_destroy (pat);
+
+	murrine_set_color_rgb (cr, &color);
+	cairo_stroke (cr);
+}
+
+void 
+murrine_draw_expander (cairo_t *cr,
+	               const MurrineColors    *colors,
+	               const WidgetParameters *widget,
+	               const ExpanderParameters *expander,
+	               int x, int y, int width, int height)
+{
+	switch (expander->style)
+	{
+		default:
+		case 0:
+			murrine_draw_expander_arrow (cr, colors, widget, expander, x, y, width, height);
+			break;
+	}
+}
+
 void
 murrine_draw_focus (cairo_t *cr,
                     const MurrineColors    *colors,
@@ -2755,6 +2876,7 @@ murrine_register_style_murrine (MurrineStyleFunctions *functions)
 	functions->draw_progressbar_fill   = murrine_draw_progressbar_fill;
 	functions->draw_entry              = murrine_draw_entry;
 	functions->draw_entry_progress     = murrine_draw_entry_progress;
+	functions->draw_expander           = murrine_draw_expander;
 	functions->draw_slider_handle      = murrine_draw_slider_handle;
 	functions->draw_spinbutton         = murrine_draw_spinbutton;
 	functions->draw_spinbutton_down    = murrine_draw_spinbutton_down;
diff --git a/src/murrine_style.c b/src/murrine_style.c
index 38e8bfd..cf28ce9 100644
--- a/src/murrine_style.c
+++ b/src/murrine_style.c
@@ -2076,64 +2076,31 @@ murrine_style_draw_expander (GtkStyle        *style,
 {
 	MurrineStyle  *murrine_style = MURRINE_STYLE (style);
 	MurrineColors *colors = &murrine_style->colors;
-	WidgetParameters params;
+
 	cairo_t *cr;
-	gint expander_size;
 
 	CHECK_ARGS
 
 	cr = murrine_begin_paint (window, area);
 
+	WidgetParameters params;
+	ExpanderParameters expander;
+
 	murrine_set_widget_parameters (widget, style, state_type, &params);
 
 	if (widget &&
 	    gtk_widget_class_find_style_property (GTK_WIDGET_GET_CLASS (widget), "expander-size"))
 	{
-		gtk_widget_style_get (widget, "expander-size", &expander_size, NULL);
+		gtk_widget_style_get (widget, "expander-size", &expander.size, NULL);
 	}
 	else
-		expander_size = 13;
-
-	if (expander_size % 2 == 0)
-		expander_size--;
-
-	cairo_translate (cr, x-expander_size/2, y-expander_size/2);
+		expander.size = 7;
 
-	cairo_save (cr);
-
-	murrine_rounded_rectangle_closed (cr, 1, 1, expander_size-2, expander_size-2, params.roundness, params.corners);
-	cairo_clip_preserve (cr);
-
-	murrine_draw_glaze (cr, &colors->bg[state_type],
-	                    params.glow_shade, params.highlight_shade, params.lightborder_shade,
-	                    params.mrn_gradient, &params, 1, 1, expander_size-2, expander_size-2,
-	                    params.roundness, params.corners, TRUE);
-
-	cairo_restore (cr);
-
-	switch (expander_style)
-	{
-		case GTK_EXPANDER_SEMI_COLLAPSED:
-		case GTK_EXPANDER_COLLAPSED:
-			cairo_move_to (cr, (double)expander_size/2-expander_size/4-0.5, (double)expander_size/2);
-			cairo_line_to (cr, (double)expander_size/2+expander_size/4+0.5, (double)expander_size/2);
-			cairo_move_to (cr, (double)expander_size/2, (double)expander_size/2-expander_size/4-0.5);
-			cairo_line_to (cr, (double)expander_size/2, (double)expander_size/2+expander_size/4+0.5);
-		break;
-		case GTK_EXPANDER_SEMI_EXPANDED:
-		case GTK_EXPANDER_EXPANDED:
-			cairo_move_to (cr, (double)expander_size/2-expander_size/4-0.5, (double)expander_size/2);
-			cairo_line_to (cr, (double)expander_size/2+expander_size/4+0.5, (double)expander_size/2);
-		break;
-		default:
-			g_assert_not_reached ();
-	}
-	murrine_set_color_rgb  (cr, &colors->fg[state_type]);
-	cairo_stroke (cr);
+	expander.expander_style = expander_style;
+	expander.text_direction = murrine_get_direction (widget);
+	expander.style = 0;
 
-	murrine_rounded_rectangle (cr, 0.5, 0.5, expander_size-1, expander_size-1, params.roundness, params.corners);
-	murrine_set_color_rgb (cr, &colors->shade[4]);
-	cairo_stroke (cr);
+	STYLE_FUNCTION(draw_expander) (cr, colors, &params, &expander, x, y, expander.size, expander.size);
 
 	cairo_destroy (cr);
 }
diff --git a/src/murrine_types.h b/src/murrine_types.h
index d5e410e..80e3403 100644
--- a/src/murrine_types.h
+++ b/src/murrine_types.h
@@ -238,6 +238,15 @@ typedef struct
 
 typedef struct
 {
+	boolean in_treeview;	
+	int size;
+	int style;
+	GtkExpanderStyle expander_style;
+	GtkTextDirection text_direction;
+} ExpanderParameters;
+
+typedef struct
+{
 	MurrineFocusType    type;
 	MurrineContinue     continue_side;
 	MurrineRGB          color;
@@ -422,6 +431,12 @@ struct _MurrineStyleFunctions
 	                               const EntryProgressParameters *progress,
 	                               int x, int y, int width, int height);
 
+	void (*draw_expander) (cairo_t *cr,
+	                       const MurrineColors    *colors,
+	                       const WidgetParameters *widget,
+	                       const ExpanderParameters *expander,
+	                       int x, int y, int width, int height);
+
 	void (*draw_spinbutton) (cairo_t *cr,
 	                         const MurrineColors    *colors,
 	                         const WidgetParameters *widget,