fastmeter: 1px padding left&right

[ardour.git] / libs / gtkmm2ext / fastmeter.cc

diff --git a/libs/gtkmm2ext/fastmeter.cc b/libs/gtkmm2ext/fastmeter.cc
index 79d287145995b8b44a5051793e9ab010a9e3085c..ff2cb68fe99dd977d4e5f788ccb05462b2db6fec 100644 (file)
--- a/libs/gtkmm2ext/fastmeter.cc
+++ b/libs/gtkmm2ext/fastmeter.cc
@@ -45,6 +45,7 @@ FastMeter::FastMeter (long hold, unsigned long dimen, Orientation o, int len, in
 {
        orientation = o;
        hold_cnt = hold;
+       resized = true;
        hold_state = 0;
        current_peak = 0;
        current_level = 0;
@@ -57,7 +58,7 @@ FastMeter::FastMeter (long hold, unsigned long dimen, Orientation o, int len, in
 
        set_events (BUTTON_PRESS_MASK|BUTTON_RELEASE_MASK);
 
-       pixrect.x = 0;
+       pixrect.x = 1;
        pixrect.y = 0;
 
        if (orientation == Vertical) {
@@ -77,14 +78,14 @@ FastMeter::FastMeter (long hold, unsigned long dimen, Orientation o, int len, in
        }
 
        if (orientation == Vertical) {
-               pixrect.width = min (pixwidth, (gint) dimen);
+               pixrect.width = pixwidth;
                pixrect.height = pixheight;
        } else {
                pixrect.width = pixwidth;
                pixrect.height = min (pixheight, (gint) dimen);
        }
 
-       request_width = pixrect.width;
+       request_width = pixrect.width + 2;
        request_height= pixrect.height;
 }
 
@@ -94,10 +95,16 @@ FastMeter::generate_meter_pattern (
 {
        guint8 r0,g0,b0,r1,g1,b1,r2,g2,b2,r3,g3,b3,a;
 
-       /* clr0: color at top of the meter
-             1: color at the knee
-              2: color half-way between bottom and knee
-             3: color at the bottom of the meter
+       /*
+         The knee is the hard transition point (e.g. at 0dB where the colors
+         change dramatically to make clipping apparent). Thus there are two
+         gradients in the pattern, the "normal range" and the "clip range", which
+         are separated at the knee point.
+
+         clr0: color at bottom of normal range gradient
+         clr1: color at top of normal range gradient
+         clr2: color at bottom of clip range gradient
+         clr3: color at top of clip range gradient
        */
 
        UINT_TO_RGBA (clr0, &r0, &g0, &b0, &a);
@@ -112,18 +119,30 @@ FastMeter::generate_meter_pattern (
        //  return def / 115.0f
 
        const int knee = (int)floor((float)height * 100.0f / 115.0f);
-       cairo_pattern_t* _p = cairo_pattern_create_linear (0.0, 0.0, width, height);
+       cairo_pattern_t* pat = cairo_pattern_create_linear (0.0, 0.0, width, height);
 
-       /* cairo coordinate space goes downwards as y value goes up, so invert
-        * knee-based positions by using (1.0 - y)
-        */
+       /*
+         Cairo coordinate space goes downwards as y value goes up, so invert
+         knee-based positions by using (1.0 - y)
+       */
+
+       // Clip range top
+       cairo_pattern_add_color_stop_rgb (pat, 0.0,
+                                         r3/255.0, g3/255.0, b3/255.0);
+
+       // Clip range bottom
+       cairo_pattern_add_color_stop_rgb (pat, 1.0 - (knee/(double)height),
+                                         r2/255.0, g2/255.0, b2/255.0);
 
-       cairo_pattern_add_color_stop_rgb (_p, 0.0, r3/255.0, g3/255.0, b3/255.0); // bottom
-       cairo_pattern_add_color_stop_rgb (_p, 1.0 - (knee/(double)height), r2/255.0, g2/255.0, b2/255.0); // mid-point to knee
-       cairo_pattern_add_color_stop_rgb (_p, 1.0 - (knee/(2.0 * height)), r1/255.0, g1/255.0, b1/255.0); // knee to top
-       cairo_pattern_add_color_stop_rgb (_p, 1.0, r0/255.0, g0/255.0, b0/255.0); // top
+       // Normal range top (double-stop at knee)
+       cairo_pattern_add_color_stop_rgb (pat, 1.0 - (knee/(double)height),
+                                         r1/255.0, g1/255.0, b1/255.0);
 
-       Cairo::RefPtr<Cairo::Pattern> p (new Cairo::Pattern (_p, false));
+       // Normal range bottom
+       cairo_pattern_add_color_stop_rgb (pat, 1.0,
+                                         r0/255.0, g0/255.0, b0/255.0); // top
+
+       Cairo::RefPtr<Cairo::Pattern> p (new Cairo::Pattern (pat, false));
 
        return p;
 }
@@ -242,7 +261,7 @@ FastMeter::on_size_allocate (Gtk::Allocation &alloc)
                        pattern = request_vertical_meter (
                                request_width, h, _clr0, _clr1, _clr2, _clr3);
                        pixheight = h;
-                       pixwidth  = request_width;
+                       pixwidth  = request_width - 2;
                }
 
        } else {
@@ -268,6 +287,7 @@ FastMeter::on_size_allocate (Gtk::Allocation &alloc)
        }
 
        DrawingArea::on_size_allocate (alloc);
+       resized = true;
 }
 
 bool
@@ -289,6 +309,13 @@ FastMeter::vertical_expose (GdkEventExpose* ev)
        GdkRectangle background;
 
        cairo_t* cr = gdk_cairo_create (get_window ()->gobj());
+
+       if (resized) {
+               cairo_set_source_rgb (cr, 0, 0, 0); // black
+               cairo_rectangle (cr, 0, 0, pixrect.width + 2, pixheight);
+               cairo_fill (cr);
+       }
+
        cairo_rectangle (cr, ev->area.x, ev->area.y, ev->area.width, ev->area.height);
        cairo_clip (cr);
 
@@ -302,7 +329,7 @@ FastMeter::vertical_expose (GdkEventExpose* ev)
 
        background.x = 0;
        background.y = 0;
-       background.width = pixrect.width;
+       background.width = pixrect.width + 2;
        background.height = pixheight - top_of_meter;
 
        if (gdk_rectangle_intersect (&background, &ev->area, &intersection)) {
@@ -321,13 +348,13 @@ FastMeter::vertical_expose (GdkEventExpose* ev)
        // draw peak bar
 
        if (hold_state) {
-               last_peak_rect.x = 0;
+               last_peak_rect.x = 1;
                last_peak_rect.width = pixwidth;
                last_peak_rect.y = pixheight - (gint) floor (pixheight * current_peak);
                last_peak_rect.height = min(3, pixheight - last_peak_rect.y);
 
                cairo_set_source (cr, pattern->cobj());
-               cairo_rectangle (cr, 0, last_peak_rect.y, pixwidth, last_peak_rect.height);
+               cairo_rectangle (cr, 1, last_peak_rect.y, pixwidth, last_peak_rect.height);
                cairo_fill (cr);
 
        } else {
@@ -440,7 +467,7 @@ FastMeter::queue_vertical_redraw (const Glib::RefPtr<Gdk::Window>& win, float ol
 
        gint new_top = (gint) floor (pixheight * current_level);
 
-       rect.x = 0;
+       rect.x = 1;
        rect.width = pixwidth;
        rect.height = new_top;
        rect.y = pixheight - new_top;