From c04c76a0b6eb03389c4a682acf6104c4b012b552 Mon Sep 17 00:00:00 2001
From: Alexander Kojevnikov <alexander@kojevnikov.com>
Date: Mon, 17 May 2010 10:50:07 +1000
Subject: [PATCH] Add the frequency ruler

---
 src/spek-ruler.vala       | 25 +++++++++++++++++--------
 src/spek-spectrogram.vala | 18 +++++++++++++++---
 2 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/src/spek-ruler.vala b/src/spek-ruler.vala
index 684b318..07bf965 100644
--- a/src/spek-ruler.vala
+++ b/src/spek-ruler.vala
@@ -40,16 +40,16 @@ namespace Spek {
 			this.format_tick = format_tick;
 		}
 
-		public void draw (Context cr) {
+		public void draw (Context cr, bool horizontal) {
 			// Mesure the sample label.
 			TextExtents ext;
 			cr.text_extents (sample_label, out ext);
-			var label_width = ext.width;
+			var size = horizontal ? ext.width : ext.height;
 
 			// Select the factor to use, we want some space between the labels.
 			int factor = 0;
 			foreach (var f in factors) {
-				if (unit_to_pixel (f) >= 1.5 * label_width) {
+				if (unit_to_pixel (f) >= 1.5 * size) {
 					factor = f;
 					break;
 				}
@@ -59,7 +59,7 @@ namespace Spek {
 			int[] ticks = { 0, units };
 			if (factor > 0) {
 				for (var tick = factor; tick < units; tick += factor) {
-					if (unit_to_pixel (units - tick) < label_width) {
+					if (unit_to_pixel (units - tick) < size) {
 						break;
 					}
 					ticks += tick;
@@ -72,13 +72,22 @@ namespace Spek {
 			double TICK_LEN = 4;
 			foreach (var tick in ticks) {
 				var label = format_tick (tick);
-				var pos = unit_to_pixel (tick);
+				var pos = unit_to_pixel (horizontal ? tick : units - tick);
 				cr.text_extents (label, out ext);
 				// TODO: use font measurements instead ext.height
-				cr.move_to (pos - ext.width / 2, GAP + ext.height);
+				if (horizontal) {
+					cr.move_to (pos - ext.width / 2, GAP + ext.height);
+				} else {
+					cr.move_to (-ext.width - GAP, pos + ext.height / 2);
+				}
 				cr.show_text (label);
-				cr.move_to (pos, 0);
-				cr.rel_line_to (0, TICK_LEN);
+				if (horizontal) {
+					cr.move_to (pos, 0);
+					cr.rel_line_to (0, TICK_LEN);
+				} else {
+					cr.move_to (0, pos);
+					cr.rel_line_to (-TICK_LEN, 0);
+				}
 				cr.stroke ();
 			}
 		}
diff --git a/src/spek-spectrogram.vala b/src/spek-spectrogram.vala
index 407492c..a7ee3f8 100644
--- a/src/spek-spectrogram.vala
+++ b/src/spek-spectrogram.vala
@@ -30,7 +30,7 @@ namespace Spek {
 
 		private ImageSurface image;
 		private ImageSurface palette;
-		private const int PADDING = 40;
+		private const int PADDING = 60;
 		private const int GAP = 10;
 		private const int RULER = 10;
 
@@ -120,7 +120,7 @@ namespace Spek {
 				cr.paint ();
 				cr.identity_matrix ();
 
-				// Prepare to draw the time ruler.
+				// Prepare to draw the rulers.
 				cr.set_source_rgb (1, 1, 1);
 				cr.set_line_width (1);
 				cr.set_antialias (Antialias.NONE);
@@ -136,7 +136,19 @@ namespace Spek {
 					unit => (w - 2 * PADDING) * unit / duration_seconds,
 					unit => "%d:%02d".printf (unit / 60, unit % 60));
 				cr.translate (PADDING, h - PADDING);
-				time_ruler.draw (cr);
+				time_ruler.draw (cr, true);
+				cr.identity_matrix ();
+
+				// Frequency ruler.
+				var freq = source.rate / 2;
+				var rate_ruler = new Ruler (
+					"00.0 kHz",
+					{1000, 2000, 5000, 10000, 20000},
+					freq,
+					unit => (h - 2 * PADDING) * unit / freq,
+					unit => "%d.%01d kHz".printf (unit / 1000, (unit % 1000) / 100));
+				cr.translate (PADDING, PADDING);
+				rate_ruler.draw (cr, false);
 				cr.identity_matrix ();
 			}