1 files changed, 99 insertions, 0 deletions
diff --git a/gui/progress.c b/gui/progress.c
new file mode 100644
index 0000000..b7f1d39
--- /dev/null
+++ b/gui/progress.c
@@ -0,0 +1,99 @@
+/*
+ * gui/progress.c - Progress bar
+ *
+ * Written 2016 by Werner Almesberger
+ * Copyright 2016 by Werner Almesberger
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+/*
+ * Resources:
+ *
+ * http://zetcode.com/gfx/cairo/cairobackends/
+ * https://developer.gnome.org/gtk3/stable/gtk-migrating-2-to-3.html
+ */
+
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <math.h>
+
+#include <cairo/cairo.h>
+#include <gtk/gtk.h>
+
+#include "gui/common.h"
+
+
+#define	PROGRESS_BAR_HEIGHT	10
+
+
+static void progress_draw_event(GtkWidget *widget, cairo_t *cr,
+    gpointer user_data)
+{
+	GtkAllocation alloc;
+	struct gui_ctx *ctx = user_data;
+	unsigned w, x;
+
+	x = ctx->progress >> ctx->progress_scale;
+	if (!x) {
+		/* @@@ needed ? Gtk seems to always clear the the surface. */
+		cairo_set_source_rgb(cr, 1, 1, 1);
+		cairo_paint(cr);
+	}
+
+	gtk_widget_get_allocation(ctx->da, &alloc);
+	w = ctx->hist_size >> ctx->progress_scale;
+
+	cairo_save(cr);
+	cairo_translate(cr,
+	    (alloc.width - w) / 2, (alloc.height - PROGRESS_BAR_HEIGHT) / 2);
+
+	cairo_set_source_rgb(cr, 0, 0.7, 0);
+	cairo_set_line_width(cr, 0);
+	cairo_rectangle(cr, 0, 0, x, PROGRESS_BAR_HEIGHT);
+	cairo_fill(cr);
+
+	cairo_set_source_rgb(cr, 0, 0, 0);
+	cairo_set_line_width(cr, 2);
+	cairo_rectangle(cr, 0, 0, w, PROGRESS_BAR_HEIGHT);
+	cairo_stroke(cr);
+
+	cairo_restore(cr);
+}
+
+
+void setup_progress_bar(struct gui_ctx *ctx, GtkWidget *window)
+{
+	GtkAllocation alloc;
+
+	gtk_widget_get_allocation(ctx->da, &alloc);
+
+	ctx->progress_scale = 0;
+	while ((ctx->hist_size >> ctx->progress_scale) > alloc.width)
+		ctx->progress_scale++;
+	ctx->progress = 0;
+
+	g_signal_connect(G_OBJECT(ctx->da), "draw",
+	    G_CALLBACK(progress_draw_event), ctx);
+
+	redraw(ctx);
+	gtk_main_iteration_do(0);
+}
+
+
+void progress_update(struct gui_ctx *ctx)
+{
+	unsigned mask = (1 << ctx->progress_scale) - 1;
+
+	ctx->progress++;
+	if ((ctx->progress & mask) != mask)
+		return;
+
+	redraw(ctx);
+	gtk_main_iteration_do(0);
+}