Added Philipp Pertermanns oscillograph demo

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@2334 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 201 insertions, 0 deletions

diff --git a/apps/recorder/oscillograph.c b/apps/recorder/oscillograph.c
new file mode 100644
index 0000000000..c3b76c4626
--- /dev/null
+++ b/apps/recorder/oscillograph.c
@@ -0,0 +1,201 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2002 Philipp Pertermann
+ *
+ * All files in this archive are subject to the GNU General Public License.
+ * See the file COPYING in the source tree root for full license agreement.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied. 
+ *
+ ****************************************************************************/
+
+#include <stdlib.h>
+#include <sprintf.h>
+#include "menu.h"
+#include "lcd.h"
+#include "button.h"
+#include "mas.h"
+#include "system.h"
+
+/* The different drawing modes */
+#define DRAW_MODE_FILLED  0
+#define DRAW_MODE_OUTLINE 1
+#define DRAW_MODE_PIXEL   2
+#define DRAW_MODE_COUNT   3
+
+#define MAX_PEAK 0x8000
+
+/* number of ticks between two volume samples */
+static int  speed = 1;
+/* roll == true -> lcd rolls */
+static bool roll = true;
+/* see DRAW_MODE_XXX constants for valid values */
+static int  drawMode = DRAW_MODE_FILLED;
+
+/**
+ * Displays a vertically scrolling oscillosgraph using
+ * hardware scrolling of the display. The user can change
+ * speed
+ */
+Menu oscillograph(void)
+{
+    /* stores current volume value left */
+    int  left;
+    /* stores current volume value right */
+    int  right;
+    /* specifies the current position on the lcd */
+    int  y = LCD_WIDTH - 1;
+
+    /* only needed when drawing lines */
+    int  lastLeft = 0;
+    int  lastRight = 0;
+    int  lasty = 0;
+
+    bool exit = false;
+
+    /* the main loop */
+    while (!exit) {
+
+        /* read the volume info from MAS */
+        left = mas_codec_readreg(0xC) / (MAX_PEAK / (LCD_WIDTH / 2 - 2));
+        right = mas_codec_readreg(0xD) / (MAX_PEAK / (LCD_WIDTH / 2 - 2));
+
+        /* delete current line */
+        lcd_clearline(0, y, LCD_WIDTH-1, y);
+
+        switch (drawMode) {
+            case DRAW_MODE_FILLED:
+                lcd_drawline(LCD_WIDTH / 2 + 1        , y, 
+                             LCD_WIDTH / 2 + 1 + right, y);
+                lcd_drawline(LCD_WIDTH / 2 - 1        , y,
+                             LCD_WIDTH / 2 - 1 -left  , y);
+                break;
+
+            case DRAW_MODE_OUTLINE:
+                /* last position needed for lines */
+                lasty = MAX(y-1, 0);
+
+                /* Here real lines were neccessary because 
+                   anything else was ugly. */
+                lcd_drawline(LCD_WIDTH / 2 + right     , y, 
+                             LCD_WIDTH / 2 + lastRight , lasty);
+                lcd_drawline(LCD_WIDTH / 2 - left    , y,
+                             LCD_WIDTH / 2 - lastLeft, lasty);
+
+                /* have to store the old values for drawing lines
+                   the next time */
+                lastRight = right;
+                lastLeft = left;
+                break;
+
+            case DRAW_MODE_PIXEL:
+                /* straight and simple */
+                lcd_drawpixel(LCD_WIDTH / 2 + right, y);
+                lcd_drawpixel(LCD_WIDTH / 2 - left, y);
+                break;
+        }
+
+
+        /* increment and adjust the drawing position */
+        y++;
+        if (y >=  LCD_HEIGHT)
+            y = 0;
+
+        /* I roll before update because otherwise the new
+           line would appear at the wrong end of the display */
+        if (roll)
+            lcd_roll(y);
+
+        /* now finally make the new sample visible */
+        lcd_update_rect(0, MAX(y-1, 0), LCD_WIDTH, 2);
+
+        /* There are two mechanisms to alter speed:
+           1.) slowing down is achieved by increasing
+               the time waiting for user input. This
+               mechanism uses positive values.
+           2.) speeding up is achieved by leaving out
+               the user input check for (-speed) volume
+               samples. For this mechanism negative values
+               are used.
+        */
+               
+        if (speed >= 0 || ((speed < 0) && (y % (-speed) == 0))) {
+            bool draw = false;
+
+            /* speed values > 0 slow the oszi down. By user input
+               speed might become < 1. If a value < 1 was
+               passed user input would be disabled. Thus
+               it must be ensured that at least 1 is passed. */
+
+            /* react to user input */
+            switch (button_get_w_tmo(MAX(speed, 1))) {
+                case BUTTON_UP:
+                    speed++;
+                    draw = true;
+                    break;
+
+                case BUTTON_DOWN:
+                    speed--;
+                    draw = true;
+                    break;
+
+                case BUTTON_PLAY:
+                    /* pause the demo */
+                    button_get(true);
+                    break;
+
+                case BUTTON_F1:
+                    /* toggle rolling */
+                    roll = !roll;
+                    break;
+
+                case BUTTON_F2:
+                    /* step through the display modes */
+                    drawMode ++;
+                    drawMode = drawMode % DRAW_MODE_COUNT;
+
+                    /* lcd buffer might be rolled so that
+                       the transition from LCD_HEIGHT to 0 
+                       takes place in the middle of the screen.
+                       That produces ugly results in DRAW_MODE_OUTLINE
+                       mode. If rolling is enabled this change will
+                       be reverted before the next update anyway.*/
+                    lcd_roll(0);
+                    break;
+
+                case BUTTON_F3:
+                    speed = 1;
+                    draw = true;
+                    break;
+
+                case BUTTON_OFF:
+                    exit = true;
+                    break;
+            }
+
+            if (draw) {
+                char buf[16];
+                snprintf(buf, sizeof buf, "Speed: %d", -speed);
+                lcd_putsxy(0, (y + LCD_HEIGHT - 8) % LCD_HEIGHT, buf, 0);
+                lcd_update_rect(0, (y + LCD_HEIGHT - 8) % LCD_HEIGHT, 
+                                LCD_WIDTH, 8);
+            }
+        }    
+    }
+
+    /* restore to default roll position. 
+       Looks funny if you forget to do this... */
+    lcd_roll(0);
+    lcd_update();
+
+    /* standard return */
+    return MENU_OK;
+}