Add a true waveform display to the oscilloscope plugin.

* Adds some additional niftyness like a floating popup display that
is implemented in an OSD library for use by other plugins.

* Speed changes are now gradual for both views and follow a curve
derived from some fiddling around to get a nice feel.

* Refined a few behavioral things overall.

It needs a bit of help from a direct PCM channel callback so it may
capture PCM for waveform display. Also need a few other core routines
to help out for the OSD.

Messes with some keymaps. Some targets need keymaps to access the
different views. Some devices can't support the additional view
because it requires a large buffer ( > 1 s) for samples.

If the plugin buffer is small, they can still use the popup display
since the plugin is also much smaller in that case.

Slow speed waveform needs some refining so it draws gradually like
a real oscilloscope but I'll stick with what it is, for the moment.

Change-Id: Ieb5b7922a2238264e9b19a58cb437739194eb036
Reviewed-on: http://gerrit.rockbox.org/245
Reviewed-by: Michael Sevakis <jethead71@rockbox.org>
Tested-by: Michael Sevakis <jethead71@rockbox.org>

1 files changed, 470 insertions, 0 deletions

diff --git a/apps/plugins/lib/osd.c b/apps/plugins/lib/osd.c
new file mode 100644
index 0000000000..ff0533a898
--- /dev/null
+++ b/apps/plugins/lib/osd.c
@@ -0,0 +1,470 @@
+/***************************************************************************
+*             __________               __   ___.
+*   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+*   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+*   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+*   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+*                     \/            \/     \/    \/            \/
+* $Id$
+*
+* Floating on-screen display
+*
+* Copyright (C) 2012 Michael Sevakis
+*
+* 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.
+*
+* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+* KIND, either express or implied.
+*
+****************************************************************************/
+#include "plugin.h"
+#include "osd.h"
+
+#if 1
+#undef DEBUGF
+#define DEBUGF(...)
+#endif
+
+/* At this time: assumes use of the default viewport for normal drawing */
+
+/* If multiple OSD's are wanted, could convert to caller-allocated */
+static struct osd
+{
+    enum osd_status
+    {
+        OSD_DISABLED = 0,       /* Disabled entirely */
+        OSD_HIDDEN,             /* Hidden from view */
+        OSD_VISIBLE,            /* Visible on screen */
+        OSD_ERASED,             /* Erased in preparation for regular drawing */
+    } status;                   /* View status */
+    struct viewport vp;         /* Clipping viewport */
+    struct bitmap lcd_bitmap;   /* The main LCD fb bitmap */
+    struct bitmap back_bitmap;  /* The OSD backbuffer fb bitmap */
+    int maxwidth;               /* How wide may it be at most? */
+    int maxheight;              /* How high may it be at most? */
+    long timeout;               /* Current popup stay duration */
+    long hide_tick;             /* Tick when it should be hidden */
+    osd_draw_cb_fn_t draw_cb;   /* Draw update callback */
+} osd;
+
+/* Framebuffer allocation macros */
+#if LCD_DEPTH == 1
+#  if LCD_PIXELFORMAT == HORIZONTAL_PACKING
+#    define LCD_WIDTH2BYTES(w)  (((w)+7)/8)
+#    define LCD_BYTES2WIDTH(b)  ((b)*8)
+#  elif LCD_PIXELFORMAT == VERTICAL_PACKING
+#    define LCD_HEIGHT2BYTES(h) (((h)+7)/8)
+#    define LCD_BYTES2HEIGHT(b) ((b)*8)
+#  else
+#    error Unknown 1-bit format; please define macros
+#  endif /* LCD_PIXELFORMAT */
+#elif LCD_DEPTH == 2
+#  if LCD_PIXELFORMAT == HORIZONTAL_PACKING
+#    define LCD_WIDTH2BYTES(w)  (((w)+3)/4)
+#    define LCD_BYTES2WIDTH(b)  ((b)*4)
+#  elif LCD_PIXELFORMAT == VERTICAL_PACKING
+#    define LCD_HEIGHT2BYTES(h) (((h)+3)/4)
+#    define LCD_BYTES2HEIGHT(b) ((b)*4)
+#  elif LCD_PIXELFORMAT == VERTICAL_INTERLEAVED
+#    define LCD_WIDTH2BYTES(w)  ((w)*2)
+#    define LCD_BYTES2WIDTH(b)  ((b)/2)
+#    define LCD_HEIGHT2BYTES(h) (((h)+7)/8*2)
+#    define LCD_BYTES2HEIGHT(b) ((b)/2*8)
+#  else
+#    error Unknown 2-bit format; please define macros
+#  endif /* LCD_PIXELFORMAT */
+#elif LCD_DEPTH == 16
+#  define LCD_WIDTH2BYTES(w)    ((w)*2)
+#  define LCD_BYTES2WIDTH(b)    ((b)/2)
+#else
+#  error Unknown LCD depth; please define macros
+#endif /* LCD_DEPTH */
+/* Set defaults if not defined different yet. */
+#ifndef LCD_WIDTH2BYTES
+#  define LCD_WIDTH2BYTES(w)    (w)
+#endif
+#ifndef LCD_BYTES2WIDTH
+#  define LCD_BYTES2WIDTH(b)    (b)
+#endif
+#ifndef LCD_HEIGHT2BYTES
+#  define LCD_HEIGHT2BYTES(h)   (h)
+#endif
+#ifndef LCD_BYTES2HEIGHT
+#  define LCD_BYTES2HEIGHT(b)   (b)
+#endif
+
+/* Create a bitmap framebuffer from a buffer */
+static fb_data * buf_to_fb_bitmap(void *buf, size_t bufsize,
+                                  int *width, int *height)
+{
+    /* Used as dest, the LCD functions cannot deal with alternate
+       strides as of now - the stride guides the calulations. If
+       that is no longer the case, then width or height can be
+       used instead (and less memory needed for a small surface!).
+     */
+    DEBUGF("buf: %p bufsize: %lu\n", buf, (unsigned long)bufsize);
+
+#if defined(LCD_STRIDEFORMAT) && LCD_STRIDEFORMAT == VERTICAL_STRIDE
+    int h = LCD_BYTES2HEIGHT(LCD_HEIGHT2BYTES(LCD_HEIGHT));
+    int w = bufsize / LCD_HEIGHT2BYTES(h);
+
+    if (w == 0)
+    {
+        DEBUGF("OSD: not enough buffer\n");
+        return NULL; /* not enough buffer */
+    }
+#else
+    int w = LCD_BYTES2WIDTH(LCD_WIDTH2BYTES(LCD_WIDTH));
+    int h = bufsize / LCD_WIDTH2BYTES(w);
+
+    if (h == 0)
+    {
+        DEBUGF("OSD: not enough buffer\n");
+        return NULL; /* not enough buffer */
+    }
+#endif
+
+    DEBUGF("fbw:%d fbh:%d\n", w, h);
+
+    *width = w;
+    *height = h;
+   
+    return (fb_data *)buf;
+}
+
+static inline void osd_set_vp_pos(int x, int y, int width, int height)
+{
+    osd.vp.x = x;
+    osd.vp.y = y;
+    osd.vp.width = width;
+    osd.vp.height = height;
+}
+
+/* Sync the backbuffer to the on-screen image */
+static void osd_lcd_update_back_buffer(void)
+{
+    rb->lcd_set_framebuffer((fb_data *)osd.back_bitmap.data);
+    rb->lcd_bmp_part(&osd.lcd_bitmap, osd.vp.x, osd.vp.y,
+                     0, 0, osd.vp.width, osd.vp.height);
+    /* Assume it was on default framebuffer for now */
+    rb->lcd_set_framebuffer(NULL);
+}
+
+/* Erase the OSD to restore the framebuffer */
+static void osd_lcd_erase(void)
+{
+    rb->lcd_bmp_part(&osd.back_bitmap, 0, 0, osd.vp.x, osd.vp.y,
+                     osd.vp.width, osd.vp.height);
+}
+
+/* Draw the OSD image portion using the callback */
+static void osd_lcd_draw_rect(int x, int y, int width, int height)
+{
+    rb->lcd_set_viewport(&osd.vp);
+    osd.draw_cb(x, y, width, height);
+    rb->lcd_set_viewport(NULL);
+}
+
+/* Draw the OSD image using the callback */
+static void osd_lcd_draw(void)
+{
+    osd_lcd_draw_rect(0, 0, osd.vp.width, osd.vp.height);
+}
+
+
+/** Public APIs **/
+
+/* Initialized the OSD and set its backbuffer */
+bool osd_init(void *backbuf, size_t backbuf_size,
+              osd_draw_cb_fn_t draw_cb)
+{
+    osd_show(OSD_HIDE);
+
+    osd.status = OSD_DISABLED; /* Disabled unless all is okay */
+    osd_set_vp_pos(0, 0, 0, 0);
+    osd.maxwidth = osd.maxheight = 0;
+    osd.timeout = 0;
+
+    if (!draw_cb)
+        return false;
+
+    if (!backbuf)
+        return false;
+
+    ALIGN_BUFFER(backbuf, backbuf_size, FB_DATA_SZ);
+
+    if (!backbuf_size)
+        return false;
+
+    rb->viewport_set_fullscreen(&osd.vp, SCREEN_MAIN);
+
+    fb_data *backfb = buf_to_fb_bitmap(backbuf, backbuf_size,
+                                       &osd.maxwidth, &osd.maxheight);
+
+    if (!backfb)
+        return false;
+
+    osd.draw_cb = draw_cb;
+
+    /* LCD framebuffer bitmap */
+    osd.lcd_bitmap.width = LCD_BYTES2WIDTH(LCD_WIDTH2BYTES(LCD_WIDTH));
+    osd.lcd_bitmap.height = LCD_BYTES2HEIGHT(LCD_HEIGHT2BYTES(LCD_HEIGHT));
+#if LCD_DEPTH > 1
+    osd.lcd_bitmap.format = FORMAT_NATIVE;
+    osd.lcd_bitmap.maskdata = NULL;
+#endif
+#ifdef HAVE_LCD_COLOR
+    osd.lcd_bitmap.alpha_offset = 0;
+#endif
+    osd.lcd_bitmap.data = (void *)rb->lcd_framebuffer;
+
+    /* Backbuffer bitmap */
+    osd.back_bitmap.width = osd.maxwidth;
+    osd.back_bitmap.height = osd.maxheight;
+#if LCD_DEPTH > 1
+    osd.back_bitmap.format = FORMAT_NATIVE;
+    osd.back_bitmap.maskdata = NULL;
+#endif
+#ifdef HAVE_LCD_COLOR
+    osd.back_bitmap.alpha_offset = 0;
+#endif
+    osd.back_bitmap.data = (void *)backfb;
+
+    DEBUGF("FB:%p BB:%p\n", osd.lcd_bitmap.data, osd.back_bitmap.data);
+
+    /* Set the default position to the whole thing */
+    osd_set_vp_pos(0, 0, osd.maxwidth, osd.maxheight);
+
+    osd.status = OSD_HIDDEN; /* Ready when you are */
+    return true;
+}
+
+/* Show/Hide the OSD on screen */
+bool osd_show(unsigned flags)
+{
+    if (flags & OSD_SHOW)
+    {
+        switch (osd.status)
+        {
+        case OSD_DISABLED:
+            break; /* No change */
+
+        case OSD_HIDDEN:
+            osd_lcd_update_back_buffer();
+            osd.status = OSD_VISIBLE;
+            osd_update();
+            osd.hide_tick = *rb->current_tick + osd.timeout;
+            break;
+
+        case OSD_VISIBLE:
+            if (flags & OSD_UPDATENOW)
+                osd_update();
+            /* Fall-through */
+        case OSD_ERASED:
+            osd.hide_tick = *rb->current_tick + osd.timeout;
+            return true;
+        }
+    }
+    else
+    {
+        switch (osd.status)
+        {
+        case OSD_DISABLED:
+        case OSD_HIDDEN:
+            break;
+
+        case OSD_VISIBLE:
+            osd_lcd_erase();
+            rb->lcd_update_rect(osd.vp.x, osd.vp.y, osd.vp.width,
+                                osd.vp.height);
+        /* Fall-through */
+        case OSD_ERASED:
+            osd.status = OSD_HIDDEN;
+            return true;
+        }
+    }
+
+    return false;
+}
+
+/* Redraw the entire OSD */
+bool osd_update(void)
+{
+    if (osd.status != OSD_VISIBLE)
+        return false;
+
+    osd_lcd_draw();
+
+    rb->lcd_update_rect(osd.vp.x, osd.vp.y, osd.vp.width,
+                        osd.vp.height);
+
+    return true;
+}
+
+/* Redraw part of the OSD (viewport-relative coordinates) */
+bool osd_update_rect(int x, int y, int width, int height)
+{
+    if (osd.status != OSD_VISIBLE)
+        return false;
+
+    osd_lcd_draw_rect(x, y, width, height);
+
+    if (x + width > osd.vp.width)
+        width = osd.vp.width - x;
+
+    if (x < 0)
+    {
+        width += x;
+        x = 0;
+    }
+
+    if (width <= 0)
+        return false;
+
+    if (y + height > osd.vp.height)
+        height = osd.vp.height - y;
+
+    if (y < 0)
+    {
+        height += y;
+        y = 0;
+    }
+
+    if (height <= 0)
+        return false;
+
+    rb->lcd_update_rect(osd.vp.x + x, osd.vp.y + y, width, height);
+
+    return true;
+}
+
+/* Set a new screen location and size (screen coordinates) */
+bool osd_update_pos(int x, int y, int width, int height)
+{
+    if (osd.status == OSD_DISABLED)
+        return false;
+
+    if (width < 0)
+        width = 0;
+    else if (width > osd.maxwidth)
+        width = osd.maxwidth;
+
+    if (height < 0)
+        height = 0;
+    else if (height > osd.maxheight)
+        height = osd.maxheight;
+
+    if (x == osd.vp.x && y == osd.vp.y &&
+        width == osd.vp.width && height == osd.vp.height)
+        return false; /* No change */
+
+    if (osd.status != OSD_VISIBLE)
+    {
+        /* Not visible - just update pos */
+        osd_set_vp_pos(x, y, width, height);
+        return false;
+    }
+
+    /* Visible area has changed */
+    osd_lcd_erase();
+
+    /* Update the smallest rectangle that encloses both the old and new
+       regions to make the change free of flicker (they may overlap) */
+    int xu = MIN(osd.vp.x, x);
+    int yu = MIN(osd.vp.y, y);
+    int wu = MAX(osd.vp.x + osd.vp.width, x + width) - xu;
+    int hu = MAX(osd.vp.y + osd.vp.height, y + height) - yu;
+
+    osd_set_vp_pos(x, y, width, height);
+    osd_lcd_update_back_buffer();
+    osd_lcd_draw();
+
+    rb->lcd_update_rect(xu, yu, wu, hu);
+    return true;
+}
+
+/* Call periodically to have the OSD timeout and hide itself */
+void osd_monitor_timeout(void)
+{
+    if (osd.status <= OSD_HIDDEN)
+        return; /* Already hidden/disabled */
+
+    if (osd.timeout > 0 && TIME_AFTER(*rb->current_tick, osd.hide_tick))
+        osd_show(OSD_HIDE);
+}
+
+/* Set the OSD timeout value. <= 0 = never timeout */
+void osd_set_timeout(long timeout)
+{
+    if (osd.status == OSD_DISABLED)
+        return;
+
+    osd.timeout = timeout;
+    osd_monitor_timeout();
+}
+
+/* Use the OSD viewport context */
+struct viewport * osd_get_viewport(void)
+{
+    return &osd.vp;
+}
+
+/* Get the maximum dimensions calculated by osd_init() */
+void osd_get_max_dims(int *maxwidth, int *maxheight)
+{
+    if (maxwidth)
+        *maxwidth = osd.maxwidth;
+
+    if (maxheight)
+        *maxheight = osd.maxheight;
+}
+
+/* Is the OSD enabled? */
+bool osd_enabled(void)
+{
+    return osd.status != OSD_DISABLED;
+}
+
+
+/** LCD update substitutes **/
+
+/* Prepare LCD framebuffer for regular drawing */
+void osd_lcd_update_prepare(void)
+{
+    if (osd.status == OSD_VISIBLE)
+    {
+        osd.status = OSD_ERASED;
+        osd_lcd_erase();
+    }
+}
+
+/* Update the whole screen */
+void osd_lcd_update(void)
+{
+    if (osd.status == OSD_ERASED)
+    {
+        /* Save the screen image underneath and restore the OSD image */
+        osd.status = OSD_VISIBLE;
+        osd_lcd_update_back_buffer();
+        osd_lcd_draw();
+    }
+
+    rb->lcd_update();
+}
+
+/* Update a part of the screen */
+void osd_lcd_update_rect(int x, int y, int width, int height)
+{
+    if (osd.status == OSD_ERASED)
+    {
+        /* Save the screen image underneath and restore the OSD image */
+        osd.status = OSD_VISIBLE;
+        osd_lcd_update_back_buffer();
+        osd_lcd_draw();
+    }
+
+    rb->lcd_update_rect(x, y, width, height);
+}