lua move RLIMAGE to own file

Change-Id: Icd10e4c348deec7729d4a6e2bf1152e1dfc70243

1 files changed, 1452 insertions, 0 deletions

diff --git a/apps/plugins/lua/rocklib_img.c b/apps/plugins/lua/rocklib_img.c
new file mode 100644
index 0000000000..083679cdbb
--- /dev/null
+++ b/apps/plugins/lua/rocklib_img.c
@@ -0,0 +1,1452 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2008 Dan Everton (safetydan)
+ * Copyright (C) 2009 Maurus Cuelenaere
+ * Copyright (C) 2017 William Wilgus
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+#define lrockimg_c
+#define LUA_LIB
+
+#include "lua.h"
+#include "lauxlib.h"
+#include "rocklib.h"
+#include "rocklib_img.h"
+
+/*
+ * -----------------------------------------------------------------------------
+ *
+ *  Rockbox Lua image wrapper
+ *
+ *  Some devices(1-bit / 2-bit displays) have packed bit formats that
+ *  need to be unpacked in order to work on them at a pixel level.
+ *
+ *  The internal formats of these devices do not follow the same paradigm
+ *  for image sizes either; We still display the actual width and height to
+ *  the user but store stride based on the native values
+ *
+ *  Conversion between native addressing and per pixel addressing
+ *  incurs extra overhead but it is much faster to do it
+ *  on the 'C' side rather than in lua.
+ *
+ * -----------------------------------------------------------------------------
+ */
+
+#define ROCKLUA_IMAGE LUA_ROCKLIBNAME ".image"
+
+/* mark for RLI to LUA Interface functions (luaState *L) is the only argument */
+#define RLI_LUA static int
+
+#ifndef ABS
+#define ABS(a)(((a) < 0) ? - (a) :(a))
+#endif
+
+#ifndef LCD_BLACK
+#define LCD_BLACK 0x0
+#endif
+
+struct rocklua_image
+{
+    int     width;
+    int     height;
+    int     stride;
+    size_t  elems;
+    fb_data *data;
+    fb_data dummy[1];
+};
+
+/* holds iterator data for rlimages */
+struct rli_iter_d
+{
+    struct rocklua_image *img;
+    fb_data *elem;
+    int x , y;
+    int x1, y1;
+    int x2, y2;
+    int dx, dy;
+};
+
+/* __tostring information enums */
+enum rli_info {RLI_INFO_ALL = 0, RLI_INFO_TYPE, RLI_INFO_WIDTH,
+               RLI_INFO_HEIGHT, RLI_INFO_ELEMS, RLI_INFO_BYTES,
+               RLI_INFO_DEPTH, RLI_INFO_FORMAT, RLI_INFO_ADDRESS};
+
+#ifdef HAVE_LCD_COLOR
+
+static inline fb_data invert_color(fb_data rgb)
+{
+    uint8_t r = 0xFFU - FB_UNPACK_RED(rgb);
+    uint8_t g = 0xFFU - FB_UNPACK_RED(rgb);
+    uint8_t b = 0xFFU - FB_UNPACK_RED(rgb);
+
+    return FB_RGBPACK(r, g, b);
+}
+#else /* !HAVE_LCD_COLOR */
+
+#define invert_color(c) (~c)
+
+#endif /* HAVE_LCD_COLOR */
+
+
+#if (LCD_DEPTH > 2) /* no native to pixel mapping needed */
+
+#define pixel_to_fb(x, y, o, n) {(void) x; (void) y; do { } while (0);}
+#define pixel_to_native(x, y, xn, yn) {*xn = x; *yn = y;}
+#define init_pixelmask(x, y, m, p) do { } while (0)
+
+
+#else /* some devices need x | y coords shifted to match native format */
+
+static fb_data x_shift = FB_SCALARPACK(0);
+static fb_data y_shift = FB_SCALARPACK(0);
+static fb_data xy_mask = FB_SCALARPACK(0);
+static const fb_data *pixelmask = NULL;
+
+/* conversion between packed native formats and individual pixel addressing */
+static inline void init_pixelmask(fb_data *x_shift, fb_data *y_shift,
+                                  fb_data *xy_mask, const fb_data **pixelmask)
+{
+
+#if(LCD_PIXELFORMAT == VERTICAL_PACKING) && LCD_DEPTH == 1
+    static const fb_data pixelmask_v1[8] =
+               {0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80};
+    *pixelmask = pixelmask_v1;
+
+    (void) x_shift;
+    *y_shift = 3U;
+    *xy_mask = ((1 << (*y_shift)) - 1);
+#elif(LCD_PIXELFORMAT == VERTICAL_PACKING) && LCD_DEPTH == 2
+    static const fb_data pixelmask_v2[4] = {0x03, 0x0C, 0x30, 0xC0};
+    *pixelmask = pixelmask_v2;
+
+    (void) x_shift;
+    *y_shift = 2U;
+    *xy_mask = ((1 << (*y_shift)) - 1);
+#elif(LCD_PIXELFORMAT == VERTICAL_INTERLEAVED) && LCD_DEPTH == 2
+    static const fb_data pixelmask_vi2[8] =
+               {0x0101, 0x0202, 0x0404, 0x0808, 0x1010, 0x2020, 0x4040, 0x8080};
+    *pixelmask = pixelmask_vi2;
+
+    (void) x_shift;
+    *y_shift = 3U;
+    *xy_mask = ((1 << (*y_shift)) - 1);
+#elif(LCD_PIXELFORMAT == HORIZONTAL_PACKING) && LCD_DEPTH == 2
+    /* MSB on left */
+    static const fb_data pixelmask_h2[4] = {0x03, 0x0C, 0x30, 0xC0};
+    *pixelmask = pixelmask_h2;
+
+    (void) y_shift;
+    *x_shift = 2U;
+    *xy_mask = ((1 << (*x_shift)) - 1);
+#else
+    #warning Unknown Pixel Format
+#endif /* LCD_PIXELFORMAT */
+
+} /* init_pixelmask */
+
+static inline void pixel_to_native(int x, int y, int *x_native, int *y_native)
+{
+    *x_native = ((x - 1) >> x_shift) + 1;
+    *y_native = ((y - 1) >> y_shift) + 1;
+} /* pixel_to_native */
+
+static inline fb_data set_masked_pixel(fb_data old,
+                                       fb_data new,
+                                       fb_data mask,
+                                       int bit_n)
+{
+    /*equivalent of: (old & (~mask)) | ((new << bit_n) & mask);*/
+    return old ^ ((old ^ (new << bit_n)) & mask);
+
+} /* set_masked_pixel */
+
+static inline fb_data get_masked_pixel(fb_data val, fb_data mask, int bit_n)
+{
+    val = val & mask;
+    return val >> bit_n;
+} /* get_masked_pixel */
+
+/* conversion between packed native formats and individual pixel addressing */
+static void pixel_to_fb(int x, int y, fb_data *oldv, fb_data *newv)
+{
+    fb_data mask;
+    int bit_n;
+
+#if(LCD_PIXELFORMAT == VERTICAL_INTERLEAVED) && LCD_DEPTH == 2
+    (void) x;
+    const uint16_t greymap_vi2[4] = {0x0000, 0x0001, 0x0100, 0x0101};
+
+    bit_n = (y - 1) & xy_mask;
+    mask  = pixelmask[bit_n];
+
+    *newv = greymap_vi2[*newv &(0x3)]; /* [0-3] => greymap */
+    *newv = set_masked_pixel(*oldv, *newv, mask, bit_n);
+
+    *oldv = get_masked_pixel(*oldv, mask, bit_n);
+
+    if((*oldv) > 1) /* greymap => [0-3] */
+        *oldv = ((*oldv) & 0x1U) + 2U; /* 2, 3 */
+    else
+        *oldv &= 1U; /* 0, 1 */
+
+#elif(LCD_DEPTH <= 2)
+    if(y_shift)
+        bit_n = (y - 1) & xy_mask;
+    else if(x_shift)
+        bit_n = xy_mask - ((x - 1) & xy_mask); /*MSB on left*/
+
+    if(y_shift || x_shift)
+    {
+        mask   = pixelmask[bit_n];
+        bit_n *= LCD_DEPTH;
+
+        *newv = set_masked_pixel(*oldv, *newv, mask, bit_n);
+
+        *oldv = get_masked_pixel(*oldv, mask, bit_n);
+    }
+#else
+    #error Unknown Pixel Format
+#endif /* LCD_PIXELFORMAT == VERTICAL_INTERLEAVED && LCD_DEPTH == 2 */
+} /* pixel_to_fb */
+
+#endif /* (LCD_DEPTH > 2) no native to pixel mapping needed */
+
+/* Internal worker functions for image data array *****************************/
+
+static inline void swap_int(bool swap, int *v1, int *v2)
+{
+    if(swap)
+    {
+        int val = *v1;
+        *v1 = *v2;
+        *v2 = val;
+    }
+} /* swap_int */
+
+/* Throws error if x or y are out of bounds notifies user which narg indice
+   the out of bound variable originated */
+static void bounds_check_xy(lua_State *L, struct rocklua_image *img,
+                         int nargx, int x, int nargy, int y)
+{
+    luaL_argcheck(L, x <= img->width && x > 0,  nargx, ERR_IDX_RANGE);
+    luaL_argcheck(L, y <= img->height && y > 0, nargy, ERR_IDX_RANGE);
+} /* bounds_check_xy */
+
+static struct rocklua_image* rli_checktype(lua_State *L, int arg)
+{
+    void *ud = luaL_checkudata(L, arg, ROCKLUA_IMAGE);
+
+    luaL_argcheck(L, ud != NULL, arg, "'" ROCKLUA_IMAGE "' expected");
+
+    return (struct rocklua_image*) ud;
+} /* rli_checktype */
+
+static struct rocklua_image * alloc_rlimage(lua_State *L, bool alloc_data,
+                                            int width, int height)
+{
+    /* rliimage is pushed on the stack it is up to you to pop it */
+    struct rocklua_image *img;
+
+    const size_t sz_header = sizeof(struct rocklua_image);
+    size_t sz_data = 0;
+    size_t n_elems;
+
+    int w_native;
+    int h_native;
+
+    pixel_to_native(width, height, &w_native, &h_native);
+
+    n_elems = (size_t)(w_native * h_native);
+
+    if(alloc_data) /* if this a new image we need space for image data */
+        sz_data = n_elems * sizeof(fb_data);
+
+    /* newuserdata pushes the userdata onto the stack */
+    img = (struct rocklua_image *) lua_newuserdata(L, sz_header + sz_data);
+
+    luaL_getmetatable(L, ROCKLUA_IMAGE);
+    lua_setmetatable(L, -2);
+
+    /* apparent w/h is stored but behind the scenes native w/h is used */
+    img->width  = width;
+    img->height = height;
+    img->stride = w_native;
+    img->elems  = n_elems;
+
+    return img;
+} /* alloc_rlimage */
+
+static inline void rli_wrap(lua_State *L, fb_data *src, int width, int height)
+{
+    /* rliimage is pushed on the stack it is up to you to pop it */
+    struct rocklua_image *a = alloc_rlimage(L, false, width, height);
+
+    a->data = src;
+} /* rli_wrap */
+
+static inline fb_data* rli_alloc(lua_State *L, int width, int height)
+{
+    /* rliimage is pushed on the stack it is up to you to pop it */
+    struct rocklua_image *a = alloc_rlimage(L, true, width, height);
+
+    a->data = &a->dummy[0]; /* ref to beginning of alloc'd img data */
+
+    return a->data;
+} /* rli_alloc */
+
+static inline fb_data data_setget(fb_data *elem, int x, int y, fb_data *val)
+{
+    fb_data old_val = FB_SCALARPACK(0);
+    fb_data new_val;
+
+    if(elem)
+    {
+        old_val = *elem;
+
+        if(val)
+        {
+            new_val = *val;
+            pixel_to_fb(x, y, &old_val, &new_val);
+            *elem = new_val;
+        }
+        else
+            pixel_to_fb(x, y, &old_val, &new_val);
+    }
+
+    return old_val;
+} /* data_setget */
+
+static inline fb_data data_set(fb_data *elem, int x, int y, fb_data *new_val)
+{
+    /* get and set share the same underlying function */
+    return data_setget(elem, x, y, new_val);
+} /* data_set */
+
+static inline fb_data data_get(fb_data *elem, int x, int y)
+{
+    /* get and set share the same underlying function */
+    return data_setget(elem, x, y, NULL);
+} /* data_get */
+
+static fb_data* rli_get_element(struct rocklua_image* img, int x, int y)
+{
+    int stride      = img->stride;
+    size_t elements = img->elems;
+    fb_data *data   = img->data;
+
+    pixel_to_native(x, y, &x, &y);
+
+    /* row major address */
+    size_t data_address = (stride * (y - 1)) + (x - 1);
+
+    /* x needs bound between 0 and stride otherwise overflow to prev/next y */
+    if(x <= 0 || x > stride || data_address >= elements)
+        return NULL; /* data overflow */
+
+    return &data[data_address]; /* return element address */
+} /* rli_get_element */
+
+/* Lua to C Interface for pixel set and get functions */
+static int rli_setget(lua_State *L, bool is_get)
+{
+    /*(set) (dst*, [x1, y1, clr, clip]) */
+    /*(get) (dst*, [x1, y1, clip]) */
+    struct rocklua_image *a = rli_checktype(L, 1);
+    int x = luaL_checkint(L, 2);
+    int y = luaL_checkint(L, 3);
+
+    fb_data clr = FB_SCALARPACK(0); /* Arg 4 is color if set element */
+    fb_data *p_clr = &clr;
+
+    int clip_narg;
+
+    if(is_get) /* get element */
+    {
+        p_clr = NULL;
+        clip_narg = 4;
+    }
+    else /* set element */
+    {
+        clr = FB_SCALARPACK((unsigned) luaL_checknumber(L, 4));
+        clip_narg = 5;
+    }
+
+    fb_data *element = rli_get_element(a, x, y);
+
+    if(!element)
+    {
+        if(!luaL_optboolean(L, clip_narg, false)) /* Error if !clip */
+            bounds_check_xy(L, a, 2, x, 3, y);
+
+        lua_pushnil(L);
+        return 1;
+    }
+
+    lua_pushnumber(L, FB_UNPACK_SCALAR_LCD(data_setget(element, x, y, p_clr)));
+
+    /* returns old value */
+    return 1;
+} /* rli_setget */
+
+#ifdef RLI_EXTENDED
+static bool init_rli_iter(struct rli_iter_d *d,
+                          struct rocklua_image *img,
+                          int x1, int y1,
+                          int x2, int y2,
+                          int dx, int dy,
+                          bool swx, bool swy)
+{
+
+    swap_int((swx), &x1, &x2);
+    swap_int((swy), &y1, &y2);
+
+    /* stepping in the correct x direction ? */
+    if((dx > 0 && x1 > x2) || (dx < 0 && x1 < x2))
+        dx = -dx;
+
+    /* stepping in the correct y direction ? */
+    if((dy > 0 && y1 > y2) || (dy < 0 && y1 < y2))
+        dy = -dy;
+
+    d->img = img;
+    d->x   = x1;
+    d->y   = y1;
+    d->x1  = x1;
+    d->y1  = y1;
+    d->x2  = x2;
+    d->y2  = y2;
+    d->dx  = dx;
+    d->dy  = dy;
+    d->elem = rli_get_element(img, d->x, d->y);
+
+    return(dx != 0 || dy != 0);
+} /* init_rli_iter */
+
+/* steps to the next point(x, y) by delta x/y, stores pointer to element
+   returns true if x & y haven't reached x2 & y2
+   if limit reached - element set to NULL, deltas set to 0 & false returned
+*/
+static bool next_rli_iter(struct rli_iter_d *d)
+{
+    if((d->dx > 0 && d->x < d->x2) || (d->dx < 0 && d->x > d->x2))
+        d->x += d->dx;
+    else if((d->dy > 0 && d->y < d->y2) || (d->dy < 0 && d->y > d->y2))
+    {
+        d->x = d->x1; /* Reset x*/
+        d->y += d->dy;
+    }
+    else
+    {
+        d->elem = NULL;
+        d->dx = 0;
+        d->dy = 0;
+        return false;
+    }
+
+    d->elem = rli_get_element(d->img, d->x, d->y);
+
+    return true;
+} /* next_rli_iter */
+
+static int d_line(struct rocklua_image *img,
+                  int x1, int y1,
+                  int x2, int y2,
+                  fb_data *clr,
+                  bool clip)
+{
+    /* NOTE! clr passed as pointer */
+    /* Bresenham midpoint line algorithm */
+    fb_data *element;
+
+    int r_a = x2 - x1; /* range of x direction called 'a' for now */
+    int r_b = y2 - y1; /* range of y direction called 'b' for now */
+
+    int s_a = 1; /* step of a direction */
+    int s_b = 1; /* step of b direction */
+
+    int d_err;
+    int numpixels;
+
+    int *a1 = &x1; /* pointer to the x var 'a' */
+    int *b1 = &y1; /* pointer to the y var 'b' */
+
+    if(r_a < 0) /* instead of negative range we will switch step instead */
+    {
+        r_a = -r_a;
+        s_a = -s_a;
+    }
+
+    if(r_b < 0) /* instead of negative range we will switch step instead */
+    {
+        r_b = -r_b;
+        s_b = -s_b;
+    }
+
+    x2 += s_a; /* add 1 extra point to make the whole line */
+    y2 += s_b; /* add 1 extra point */
+
+    if(r_b > r_a) /*if rangeY('b') > rangeX('a') swap their identities */
+    {
+        a1 = &y1;
+        b1 = &x1;
+        swap_int((true), &r_a, &r_b);
+        swap_int((true), &s_a, &s_b);
+    }
+
+    d_err = ((r_b << 1) - r_a) >> 1; /* preload err of 1 step (px centered) */
+
+    numpixels = r_a + 1;
+
+    r_a -= r_b; /* pre-subtract 'a' - 'b' */
+
+    for(;numpixels > 0; numpixels--)
+    {
+        element = rli_get_element(img, x1, y1);
+        if(element || clip)
+            data_set(element, x1, y1, clr);
+        else
+            return numpixels + 1; /* Error */
+
+        if(d_err >= 0) /* 0 is our target midpoint(exact point on the line) */
+        {
+            *b1 += s_b; /* whichever axis is in 'b' stepped(-1 or +1) */
+            d_err -= r_a;
+        }
+        else
+            d_err += r_b; /* only add 'b' when d_err < 0 */
+
+        *a1 += s_a; /* whichever axis is in 'a' stepped(-1 or +1) */
+    }
+
+    return 0;
+} /* d_line */
+
+/* ellipse worker function */
+static int d_ellipse_elements(struct rocklua_image * img,
+                              int x1, int y1,
+                              int x2, int y2,
+                              int sx, int sy,
+                              fb_data *clr,
+                              fb_data *fillclr,
+                              bool clip)
+{
+    int ret = 0;
+    fb_data *element1, *element2, *element3, *element4;
+
+    if(fillclr && x1 - sx != x2 + sx)
+    {
+        ret |= d_line(img, x1, y1, x2, y1, fillclr, clip); /* I. II.*/
+        ret |= d_line(img, x1, y2, x2, y2, fillclr, clip); /* III.IV.*/
+    }
+
+    x1 -= sx; /* shift x & y */
+    y1 -= sy;
+    x2 += sx;
+    y2 += sy;
+
+    element1 = rli_get_element(img, x2, y1);
+    element2 = rli_get_element(img, x1, y1);
+    element3 = rli_get_element(img, x1, y2);
+    element4 = rli_get_element(img, x2, y2);
+
+    if(clip || (element1 && element2 && element3 && element4))
+    {
+        data_set(element1, x2, y1, clr); /*   I. Quadrant +x +y */
+        data_set(element2, x1, y1, clr); /*  II. Quadrant -x +y */
+        data_set(element3, x1, y2, clr); /* III. Quadrant -x -y */
+        data_set(element4, x2, y2, clr); /*  IV. Quadrant +x -y */
+    }
+    else
+        ret = 2; /* ERROR */
+
+    return ret;
+} /* d_ellipse_elements */
+
+static int d_ellipse(struct rocklua_image *img,
+                          int x1, int y1,
+                          int x2, int y2,
+                          fb_data *clr,
+                          fb_data *fillclr,
+                          bool clip)
+{
+    /* NOTE! clr and fillclr passed as pointers */
+    /* Rasterizing algorithm derivative of work by Alois Zingl */
+#if LCD_WIDTH > 1024 || LCD_HEIGHT > 1024
+    /* Prevents overflow on large screens */
+    double dx, dy, err, e2;
+#else
+    long dx, dy, err, e2;
+#endif
+
+    int ret = 0;
+
+    int a = ABS(x2 - x1); /* diameter */
+    int b = ABS(y2 - y1); /* diameter */
+
+    if(a == 0 || b == 0 || !clr)
+        return ret; /* not an error but nothing to display */
+
+    int b1 = (b & 1);
+    b = b - (1 - b1);
+
+    int a2 = (a * a);
+    int b2 = (b * b);
+
+    dx = ((1 - a) * b2) >> 1; /* error increment */
+    dy = (b1 * a2) >> 1;      /* error increment */
+
+    err = dx + dy + b1 * a2; /* error of 1.step */
+
+    /* if called with swapped points .. exchange them */
+    swap_int((x1 > x2), &x1, &x2);
+    swap_int((y1 > y2), &y1, &y2);
+
+    y1 += (b + 1) >> 1;
+    y2 = y1 - b1;
+
+    do
+    {
+        ret = d_ellipse_elements(img, x1, y1, x2, y2, 0, 0, clr, fillclr, clip);
+
+        e2 = err;
+
+        /* using division because you can't use bit shift on doubles.. */
+        if(e2 <= (dy / 2)) /* target midpoint - y step */
+        {
+            y1++;
+            y2--;
+            dy  += a2;
+            err += dy;
+        }
+
+        if(e2 >= (dx / 2) || err > (dy / 2)) /* target midpoint - x step */
+        {
+            x1++;
+            x2--;
+            dx  += b2;
+            err += dx;
+        }
+
+    } while(ret == 0 && x1 <= x2);
+
+    while (ret == 0 && y1 - y2 < b) /* early stop of flat ellipse a=1 finish tip */
+    {
+        ret = d_ellipse_elements(img, x1, y1, x2, y2, 1, 0, clr, fillclr, clip);
+
+        y1++;
+        y2--;
+    }
+
+    return ret;
+} /* d_ellipse */
+
+/* Lua to C Interface for line and ellipse */
+static int rli_line_ellipse(lua_State *L, bool is_ellipse)
+{
+    struct rocklua_image *a = rli_checktype(L, 1);
+
+    int x1 = luaL_checkint(L, 2);
+    int y1 = luaL_checkint(L, 3);
+    int x2 = luaL_optint(L, 4, x1);
+    int y2 = luaL_optint(L, 5, y1);
+
+    fb_data clr = FB_SCALARPACK((unsigned) luaL_checknumber(L, 6));
+
+    fb_data fillclr; /* fill color is index 7 if is_ellipse */
+    fb_data *p_fillclr = NULL;
+
+    bool clip;
+    int clip_narg;
+
+    if(is_ellipse)
+        clip_narg = 8;
+    else
+        clip_narg = 7;
+
+    clip = luaL_optboolean(L, clip_narg, false);
+
+    if(!clip)
+    {
+        bounds_check_xy(L, a, 2, x1, 3, y1);
+        bounds_check_xy(L, a, 4, x2, 5, y2);
+    }
+
+    if(is_ellipse)
+    {
+        if(!lua_isnoneornil(L, 7))
+        {
+            fillclr = FB_SCALARPACK((unsigned) luaL_checkint(L, 7));
+            p_fillclr = &fillclr;
+        }
+
+        luaL_argcheck(L, d_ellipse(a, x1, y1, x2, y2, &clr, p_fillclr, clip) == 0,
+                      1, ERR_DATA_OVF);
+    }
+    else
+        luaL_argcheck(L, d_line(a, x1, y1, x2, y2, &clr, clip) == 0,
+                      1, ERR_DATA_OVF);
+
+    return 0;
+} /* rli_line_ellipse */
+
+/* Pushes lua function from Stack at position narg to top of stack
+   and puts a reference in the global registry for later use       */
+static inline int register_luafunc(lua_State *L, int narg_funct)
+{
+        lua_pushvalue(L, narg_funct); /* lua function */
+        int lf_ref = luaL_ref(L, LUA_REGISTRYINDEX);
+        lua_settop(L, 0); /* clear C stack for use by lua function */
+        return lf_ref;
+} /* register_luafunc */
+
+/* User defined pixel manipulations through rli_copy, rli_marshal */
+static int custom_transform(lua_State *L,
+                            struct rli_iter_d *ds,
+                            struct rli_iter_d *ss,
+                            int op,
+                            fb_data *color)
+{
+    (void) color;
+
+    fb_data dst;
+    fb_data src;
+
+    unsigned int params = 3;
+    int ret = 0;
+
+    lua_rawgeti(L, LUA_REGISTRYINDEX, op);
+
+    dst = data_get(ds->elem, ds->x, ds->y);
+    lua_pushnumber(L, FB_UNPACK_SCALAR_LCD(dst));
+    lua_pushnumber(L, ds->x);
+    lua_pushnumber(L, ds->y);
+
+    if(ss) /* Allows src to be omitted */
+    {
+        params  += 3;
+        src = data_get(ss->elem, ss->x, ss->y);
+        lua_pushnumber(L, FB_UNPACK_SCALAR_LCD(src));
+        lua_pushnumber(L, ss->x);
+        lua_pushnumber(L, ss->y);
+    }
+
+    lua_call(L, params, 2); /* call custom function w/ n-params & 2 ret */
+
+    if(!lua_isnoneornil(L, -2))
+    {
+        ret = 1;
+        dst = FB_SCALARPACK((unsigned) luaL_checknumber(L, -2));
+        data_set(ds->elem, ds->x, ds->y, &dst);
+    }
+
+    if(!lua_isnoneornil(L, -1) && ss)
+    {
+        ret |= 2;
+        src = FB_SCALARPACK((unsigned) luaL_checknumber(L, -1));
+        data_set(ss->elem, ss->x, ss->y, &src);
+    }
+
+    lua_pop(L, 2);
+    return ret; /* 0 signals iterator to stop */
+} /* custom_transform */
+
+/* Pre defined pixel manipulations through rli_copy */
+static int blit_transform(lua_State *L,
+                          struct rli_iter_d *ds,
+                          struct rli_iter_d *ss,
+                          int op,
+                          fb_data *color)
+{
+    (void) L;
+    unsigned clr = FB_UNPACK_SCALAR_LCD(*color);
+    unsigned dst = FB_UNPACK_SCALAR_LCD(data_get(ds->elem, ds->x, ds->y));
+    unsigned src;
+
+    /* Reuse 0 - 7 for src / clr blits*/
+    if(op >= 30 && op <= 37)
+    {
+        op -= 30;
+        src = clr;
+    }
+    else
+        src = FB_UNPACK_SCALAR_LCD(data_get(ss->elem, ss->x, ss->y));
+
+    switch(op)
+    {
+        default:
+        /* case 30: */
+        case 0:  { dst = src;          break; }/* copyS/C  */
+        /* case 31: */
+        case 1:  { dst = src | dst;    break; }/* DorS/C   */
+        /* case 32: */
+        case 2:  { dst = src ^ dst;    break; }/* DxorS/C  */
+        /* case 33: */
+        case 3:  { dst = ~(src | dst); break; }/* nDorS/C  */
+        /* case 34: */
+        case 4:  { dst = (~src) | dst; break; }/* DornS/C  */
+        /* case 35: */
+        case 5:  { dst = src & dst;    break; }/* DandS/C  */
+        /* case 36: */
+        case 6:  { dst = src & (~dst); break; }/* nDandS/C */
+        /* case 37: */
+        case 7:  { dst = ~src;         break; }/* notS/C   */
+
+        /* mask blits */
+        case 8:  { if(src != 0) { dst = clr; } break; }/* Sand */
+        case 9:  { if(src == 0) { dst = clr; } break; }/* Snot */
+
+        case 10:  { dst  = src | clr;           break; }/* SorC  */
+        case 11:  { dst  = src ^ clr;           break; }/* SxorC */
+        case 12:  { dst  = ~(src | clr);        break; }/* nSorC */
+        case 13:  { dst  = src | (~clr);        break; }/* SornC */
+        case 14:  { dst  = src & clr;           break; }/* SandC */
+        case 15:  { dst  = (~src) & clr;        break; }/* nSandC */
+        case 16:  { dst |= (~src) | clr;        break; }/* DornSorC */
+        case 17:  { dst ^= (src & (dst ^ clr)); break; }/* DxorSandDxorC */
+
+        case 18: { if(src != clr) { dst = src; } break; }
+        case 19: { if(src == clr) { dst = src; } break; }
+        case 20: { if(src > clr)  { dst = src; } break; }
+        case 21: { if(src < clr)  { dst = src; } break; }
+
+        case 22: { if(dst != clr) { dst = src; } break; }
+        case 23: { if(dst == clr) { dst = src; } break; }
+        case 24: { if(dst > clr)  { dst = src; } break; }
+        case 25: { if(dst < clr)  { dst = src; } break; }
+
+        case 26: { if(dst != src) { dst = clr; } break; }
+        case 27: { if(dst == src) { dst = clr; } break; }
+        case 28: { if(dst > src)  { dst = clr; } break; }
+        case 29: { if(dst < src)  { dst = clr; } break; }
+
+    }/*switch op*/
+    fb_data data = FB_SCALARPACK(dst);
+    data_set(ds->elem, ds->x, ds->y, &data);
+    return 1;
+} /* blit_transform */
+
+static int invert_transform(lua_State *L,
+                            struct rli_iter_d *ds,
+                            struct rli_iter_d *ss,
+                            int op,
+                            fb_data *color)
+{
+    (void) L;
+    (void) color;
+    (void) op;
+    (void) ss;
+
+    fb_data val = invert_color(data_get(ds->elem, ds->x, ds->y));
+    data_set(ds->elem, ds->x, ds->y, &val);
+
+    return 1;
+} /* invert_transform */
+#endif /* RLI_EXTENDED */
+
+/* RLI to LUA Interface functions *********************************************/
+RLI_LUA rli_new(lua_State *L)
+{   /* [width, height] */
+    int width  = luaL_optint(L, 1, LCD_WIDTH);
+    int height = luaL_optint(L, 2, LCD_HEIGHT);
+
+    luaL_argcheck(L, width  > 0, 1, ERR_IDX_RANGE);
+    luaL_argcheck(L, height > 0, 2, ERR_IDX_RANGE);
+
+    rli_alloc(L, width, height);
+
+    return 1;
+}
+
+RLI_LUA rli_set(lua_State *L)
+{
+    /*(set) (dst*, [x1, y1, clr, clip]) */
+    /* get and set share the same underlying function */
+    return rli_setget(L, false);
+}
+
+RLI_LUA rli_get(lua_State *L)
+{
+    /*(get) (dst*, [x1, y1, clip]) */
+    /* get and set share the same underlying function */
+    return rli_setget(L, true);
+}
+
+RLI_LUA rli_height(lua_State *L)
+{
+    struct rocklua_image *a = rli_checktype(L, 1);
+    lua_pushnumber(L, a->height);
+    return 1;
+}
+
+RLI_LUA rli_width(lua_State *L)
+{
+    struct rocklua_image *a = rli_checktype(L, 1);
+    lua_pushnumber(L, a->width);
+    return 1;
+}
+
+RLI_LUA rli_equal(lua_State *L)
+{
+    struct rocklua_image *a = rli_checktype(L, 1);
+    struct rocklua_image *b = rli_checktype(L, 2);
+    lua_pushboolean(L, a->data == b->data);
+    return 1;
+}
+
+RLI_LUA rli_size(lua_State *L)
+{
+    struct rocklua_image *a = rli_checktype(L, 1);
+    lua_pushnumber(L, a->elems);
+    return 1;
+}
+
+RLI_LUA rli_raw(lua_State *L)
+{
+    /*val = (img*, index, [new_val]) */
+    struct rocklua_image *a = rli_checktype(L, 1);
+
+    size_t i = (unsigned) luaL_checkint(L, 2);
+
+    fb_data val;
+
+    luaL_argcheck(L, i > 0 && i <= (a->elems), 2, ERR_IDX_RANGE);
+
+    lua_pushnumber(L, FB_UNPACK_SCALAR_LCD(a->data[i-1]));
+
+    if(!lua_isnoneornil(L, 3))
+    {
+        val = FB_SCALARPACK((unsigned) luaL_checknumber(L, 3));
+        a->data[i-1] = val;
+    }
+
+    return 1;
+}
+
+RLI_LUA rli_tostring(lua_State *L)
+{
+    /* (img, [infoitem]) */
+    struct rocklua_image *a = rli_checktype(L, 1);
+
+    int item     = (unsigned) luaL_optint(L, 2, 0);
+    size_t bytes = a->elems * sizeof(fb_data);
+
+    switch(item)
+    {
+        default:
+        case RLI_INFO_ALL:
+        {
+            lua_pushfstring(L,
+            ROCKLUA_IMAGE ": %dx%d, %d elements, %d bytes, %d-bit depth, %d pack",
+            a->width, a->height, a->elems, bytes, LCD_DEPTH, LCD_PIXELFORMAT);
+            break;
+        }
+        case RLI_INFO_TYPE:    { lua_pushfstring(L, ROCKLUA_IMAGE   ); break; }
+        case RLI_INFO_WIDTH:   { lua_pushfstring(L, "%d", a->width  ); break; }
+        case RLI_INFO_HEIGHT:  { lua_pushfstring(L, "%d", a->height ); break; }
+        case RLI_INFO_ELEMS:   { lua_pushfstring(L, "%d", a->elems  ); break; }
+        case RLI_INFO_BYTES:   { lua_pushfstring(L, "%d", bytes     ); break; }
+        case RLI_INFO_DEPTH:   { lua_pushfstring(L, "%d", LCD_DEPTH ); break; }
+        case RLI_INFO_FORMAT:  { lua_pushfstring(L, "%d", LCD_PIXELFORMAT); break; }
+        case RLI_INFO_ADDRESS: { lua_pushfstring(L, "%p", a->data); break; }
+    }
+
+    return 1;
+}
+
+#ifdef RLI_EXTENDED
+RLI_LUA rli_ellipse(lua_State *L)
+{
+    /* (dst*, x1, y1, x2, y2, [clr, fillclr, clip]) */
+    /* line and ellipse share the same init function */
+    return rli_line_ellipse(L, true);
+}
+
+RLI_LUA rli_line(lua_State *L)
+{
+    /* (dst*, x1, y1, [x2, y2, clr, clip]) */
+    /* line and ellipse share the same init function */
+    return rli_line_ellipse(L, false);
+}
+
+RLI_LUA rli_iterator(lua_State *L) {
+    /* see rli_iterator_factory */
+    struct rli_iter_d *ds;
+    ds = (struct rli_iter_d *) lua_touserdata(L, lua_upvalueindex(1));
+
+    if(ds->dx != 0 || ds->dy != 0)
+    {
+        lua_pushnumber(L, FB_UNPACK_SCALAR_LCD(data_get(ds->elem, ds->x, ds->y)));
+
+        lua_pushinteger(L, ds->x);
+        lua_pushinteger(L, ds->y);
+
+        next_rli_iter(ds); /* load next element */
+
+        return 3;
+    }
+    return 0; /* nothing left to do */
+}
+
+RLI_LUA rli_iterator_factory(lua_State *L) {
+    /* (src*, [x1, y1, x2, y2, dx, dy]) */
+    struct rocklua_image *a = rli_checktype(L, 1); /*image we wish to iterate*/
+
+    struct rli_iter_d *ds;
+
+    int x1  = luaL_optint(L, 2, 1);
+    int y1  = luaL_optint(L, 3, 1);
+    int x2  = luaL_optint(L, 4, a->width  - x1 + 1);
+    int y2  = luaL_optint(L, 5, a->height - y1 + 1);
+    int dx  = luaL_optint(L, 6, 1);
+    int dy  = luaL_optint(L, 7, 1);
+
+    /* create new iter + pushed onto stack */
+    ds = (struct rli_iter_d *) lua_newuserdata(L, sizeof(struct rli_iter_d));
+
+    init_rli_iter(ds, a, x1, y1, x2, y2, dx, dy, false, false);
+
+    /* returns the iter function with embedded iter data(up values) */
+    lua_pushcclosure(L, &rli_iterator, 1);
+
+    return 1;
+}
+
+RLI_LUA rli_marshal(lua_State *L) /* also invert */
+{
+    /* (img*, [x1, y1, x2, y2, dx, dy, clip, function]) */
+    struct rocklua_image *a = rli_checktype(L, 1);
+
+    struct rli_iter_d ds;
+
+    int x1 = luaL_optint(L, 2, 1);
+    int y1 = luaL_optint(L, 3, 1);
+    int x2 = luaL_optint(L, 4, a->width);
+    int y2 = luaL_optint(L, 5, a->height);
+    int dx = luaL_optint(L, 6, 1);
+    int dy = luaL_optint(L, 7, 1);
+    bool clip    = luaL_optboolean(L, 8, false);
+
+    int lf_ref = LUA_NOREF; /* de-ref'd without consequence */
+
+    int (*rli_trans)(lua_State *, struct rli_iter_d *, struct rli_iter_d *, int, fb_data *);
+    rli_trans = invert_transform; /* default transformation */
+
+    if(!clip)
+    {
+        bounds_check_xy(L, a, 2, x1, 3, y1);
+        bounds_check_xy(L, a, 4, x2, 5, y2);
+    }
+
+    init_rli_iter(&ds, a, x1, y1, x2, y2, dx, dy, false, false);
+
+    if(lua_isfunction(L, 9)) /* custom function */
+    {
+        rli_trans = custom_transform;
+        lf_ref = register_luafunc(L, 9);
+    }
+
+    do
+    {
+        luaL_argcheck(L, clip || (ds.elem != NULL), 1, ERR_DATA_OVF);
+
+        if(!(*rli_trans)(L, &ds, NULL, lf_ref, NULL))
+            break; /* Custom op can quit early */
+
+    } while(next_rli_iter(&ds));
+
+    luaL_unref(L, LUA_REGISTRYINDEX, lf_ref); /* de-reference custom function */
+    return 0;
+}
+
+RLI_LUA rli_copy(lua_State *L)
+{
+    /* (dst*, src*, [d_x, d_y, s_x, s_y, x_off, y_off, clip, [op, funct/clr]]) */
+    struct rocklua_image *d = rli_checktype(L, 1); /*dst*/
+    struct rocklua_image *s = rli_checktype(L, 2); /*src*/
+
+    struct rli_iter_d ds; /*dst*/
+    struct rli_iter_d ss; /*src*/
+
+    /* copy whole image if possible */
+    if(s->elems == d->elems && s->width == d->width && lua_gettop(L) < 3)
+    {
+        rb->memcpy(d->data, s->data, d->elems * sizeof(fb_data));
+        return 0;
+    }
+
+    int d_x = luaL_optint(L, 3, 1);
+    int d_y = luaL_optint(L, 4, 1);
+    int s_x = luaL_optint(L, 5, 1);
+    int s_y = luaL_optint(L, 6, 1);
+
+    int w = MIN(d->width - d_x, s->width - s_x);
+    int h = MIN(d->height - d_y, s->height - s_y);
+
+    int x_off = luaL_optint(L, 7, w);
+    int y_off = luaL_optint(L, 8, h);
+
+    bool clip = luaL_optboolean(L, 9, false);
+    int op = luaL_optint(L, 10, 0);
+    fb_data clr = FB_SCALARPACK(0); /* 11 is custom function | color */
+
+    bool d_swx = (x_off < 0); /* dest swap */
+    bool d_swy = (y_off < 0);
+    bool s_swx = false; /* src  swap */
+    bool s_swy = false;
+
+    int (*rli_trans)(lua_State *, struct rli_iter_d *, struct rli_iter_d *, int, fb_data *);
+    rli_trans = blit_transform; /* default transformation */
+
+    int lf_ref = LUA_NOREF; /* de-ref'd without consequence */
+
+    if(!clip) /* Out of bounds is not allowed */
+    {
+        bounds_check_xy(L, d, 3, d_x, 4, d_y);
+        bounds_check_xy(L, s, 5, s_x, 6, s_y);
+    }
+    else if (w < 0 || h < 0) /* not an error but nothing to display */
+        return 0;
+
+    w = MIN(w, ABS(x_off));
+    h = MIN(h, ABS(y_off));
+
+    /* if(s->data == d->data) need to care about fill direction */
+    if(d_x > s_x)
+    {
+        d_swx = !d_swx;
+        s_swx = !s_swx;
+    }
+
+    if(d_y > s_y)
+    {
+        d_swy = !d_swy;
+        s_swy = !s_swy;
+    }
+
+    init_rli_iter(&ds, d, d_x, d_y, d_x + w, d_y + h, 1, 1, d_swx, d_swy);
+
+    init_rli_iter(&ss, s, s_x, s_y, s_x + w, s_y + h, 1, 1, s_swx, s_swy);
+
+    if (op == 0xFF && lua_isfunction(L, 11)) /* custom function specified.. */
+    {
+        rli_trans = custom_transform;
+        lf_ref = register_luafunc(L, 11);
+        op = lf_ref;
+    }
+    else
+        clr = FB_SCALARPACK((unsigned) luaL_optnumber(L, 11, LCD_BLACK));
+
+    do
+    {
+        if(!clip)
+        {
+            luaL_argcheck(L, ss.elem != NULL, 2, ERR_DATA_OVF);
+            luaL_argcheck(L, ds.elem != NULL, 1, ERR_DATA_OVF);
+        }
+
+        if(!(*rli_trans)(L, &ds, &ss, op, &clr))
+            break; /* Custom op can quit early */
+
+    } while(next_rli_iter(&ds) && next_rli_iter(&ss));
+
+    luaL_unref(L, LUA_REGISTRYINDEX, lf_ref); /* de-reference custom function */
+    return 0;
+}
+
+RLI_LUA rli_clear(lua_State *L)
+{
+    /* (dst*, [color, x1, y1, x2, y2, clip]) */
+    struct rocklua_image *a = rli_checktype(L, 1);
+
+    struct rli_iter_d ds;
+
+    fb_data clr = FB_SCALARPACK((unsigned) luaL_optnumber(L, 2, LCD_BLACK));
+    int x1 = luaL_optint(L, 3, 1);
+    int y1 = luaL_optint(L, 4, 1);
+    int x2 = luaL_optint(L, 5, a->width);
+    int y2 = luaL_optint(L, 6, a->height);
+    bool clip = luaL_optboolean(L, 7, false);
+
+    if(!clip)
+    {
+        bounds_check_xy(L, a, 3, x1, 4, y1);
+        bounds_check_xy(L, a, 5, x2, 6, y2);
+    }
+
+    init_rli_iter(&ds, a, x1, y1, x2, y2, 1, 1, false, false);
+
+    do
+    {
+        luaL_argcheck(L, clip || (ds.elem != NULL), 1, ERR_DATA_OVF);
+
+        data_set(ds.elem, ds.x, ds.y, &clr);
+
+    } while(next_rli_iter(&ds));
+
+    return 0;
+}
+#endif /* RLI_EXTENDED */
+
+/* Rli Image methods exported to lua */
+const struct luaL_reg rli_lib [] =
+{
+    {"__tostring", rli_tostring},
+    {"_data",      rli_raw},
+    {"__len",      rli_size},
+    {"__eq",       rli_equal},
+    {"width",      rli_width},
+    {"height",     rli_height},
+    {"set",        rli_set},
+    {"get",        rli_get},
+
+#ifdef RLI_EXTENDED
+    {"copy",       rli_copy},
+    {"clear",      rli_clear},
+    {"invert",     rli_marshal},
+    {"marshal",    rli_marshal},
+    {"points",     rli_iterator_factory},
+    {"line",       rli_line},
+    {"ellipse",    rli_ellipse},
+#endif /* RLI_EXTENDED */
+
+    {NULL, NULL}
+};
+
+LUALIB_API int rli_init(lua_State *L)
+{
+    /* some devices need x | y coords shifted to match native format */
+    /* conversion between packed native formats and individual pixel addressing */
+    init_pixelmask(&x_shift, &y_shift, &xy_mask, &pixelmask);
+
+    luaL_newmetatable(L, ROCKLUA_IMAGE);
+
+    lua_pushstring(L, "__index");
+    lua_pushvalue(L, -2);  /* pushes the metatable */
+    lua_settable(L, -3);  /* metatable.__index = metatable */
+
+    luaL_register(L, NULL, rli_lib);
+
+#ifdef RLI_EXTENDED
+    luaL_register(L, ROCKLUA_IMAGE, rli_lib);
+#endif
+    return 1;
+}
+
+/*
+ * -----------------------------
+ *
+ *  Rockbox wrappers start here!
+ *
+ * -----------------------------
+ */
+
+#define RB_WRAP(M) static int rock_##M(lua_State UNUSED_ATTR *L)
+#ifdef HAVE_LCD_BITMAP
+RB_WRAP(lcd_framebuffer)
+{
+    rli_wrap(L, rb->lcd_framebuffer, LCD_WIDTH, LCD_HEIGHT);
+    return 1;
+}
+
+RB_WRAP(lcd_mono_bitmap_part)
+{
+    struct rocklua_image *src = rli_checktype(L, 1);
+    int src_x = luaL_checkint(L, 2);
+    int src_y = luaL_checkint(L, 3);
+    int stride = luaL_checkint(L, 4);
+    int x = luaL_checkint(L, 5);
+    int y = luaL_checkint(L, 6);
+    int width = luaL_checkint(L, 7);
+    int height = luaL_checkint(L, 8);
+    int screen = luaL_optint(L, 9, SCREEN_MAIN);
+
+    rb->screens[screen]->mono_bitmap_part((const unsigned char *)src->data, src_x, src_y, stride, x, y, width, height);
+    return 0;
+}
+
+RB_WRAP(lcd_mono_bitmap)
+{
+    struct rocklua_image *src = rli_checktype(L, 1);
+    int x = luaL_checkint(L, 2);
+    int y = luaL_checkint(L, 3);
+    int width = luaL_checkint(L, 4);
+    int height = luaL_checkint(L, 5);
+    int screen = luaL_optint(L, 6, SCREEN_MAIN);
+
+    rb->screens[screen]->mono_bitmap((const unsigned char *)src->data, x, y, width, height);
+    return 0;
+}
+
+#if LCD_DEPTH > 1
+RB_WRAP(lcd_bitmap_part)
+{
+    struct rocklua_image *src = rli_checktype(L, 1);
+    int src_x = luaL_checkint(L, 2);
+    int src_y = luaL_checkint(L, 3);
+    int stride = luaL_checkint(L, 4);
+    int x = luaL_checkint(L, 5);
+    int y = luaL_checkint(L, 6);
+    int width = luaL_checkint(L, 7);
+    int height = luaL_checkint(L, 8);
+    int screen = luaL_optint(L, 9, SCREEN_MAIN);
+
+    rb->screens[screen]->bitmap_part(src->data, src_x, src_y, stride, x, y, width, height);
+    return 0;
+}
+
+RB_WRAP(lcd_bitmap)
+{
+    struct rocklua_image *src = rli_checktype(L, 1);
+    int x = luaL_checkint(L, 2);
+    int y = luaL_checkint(L, 3);
+    int width = luaL_checkint(L, 4);
+    int height = luaL_checkint(L, 5);
+    int screen = luaL_optint(L, 6, SCREEN_MAIN);
+
+    rb->screens[screen]->bitmap(src->data, x, y, width, height);
+    return 0;
+}
+
+RB_WRAP(lcd_get_backdrop)
+{
+    fb_data* backdrop = rb->lcd_get_backdrop();
+    if(backdrop == NULL)
+        lua_pushnil(L);
+    else
+        rli_wrap(L, backdrop, LCD_WIDTH, LCD_HEIGHT);
+
+    return 1;
+}
+#endif /* LCD_DEPTH > 1 */
+
+#if LCD_DEPTH == 16
+RB_WRAP(lcd_bitmap_transparent_part)
+{
+    struct rocklua_image *src = rli_checktype(L, 1);
+    int src_x = luaL_checkint(L, 2);
+    int src_y = luaL_checkint(L, 3);
+    int stride = luaL_checkint(L, 4);
+    int x = luaL_checkint(L, 5);
+    int y = luaL_checkint(L, 6);
+    int width = luaL_checkint(L, 7);
+    int height = luaL_checkint(L, 8);
+    int screen = luaL_optint(L, 9, SCREEN_MAIN);
+
+    rb->screens[screen]->transparent_bitmap_part(src->data, src_x, src_y, stride, x, y, width, height);
+    return 0;
+}
+
+RB_WRAP(lcd_bitmap_transparent)
+{
+    struct rocklua_image *src = rli_checktype(L, 1);
+    int x = luaL_checkint(L, 2);
+    int y = luaL_checkint(L, 3);
+    int width = luaL_checkint(L, 4);
+    int height = luaL_checkint(L, 5);
+    int screen = luaL_optint(L, 6, SCREEN_MAIN);
+
+    rb->screens[screen]->transparent_bitmap(src->data, x, y, width, height);
+    return 0;
+}
+#endif /* LCD_DEPTH == 16 */
+
+#endif /* defined(LCD_BITMAP) */
+
+#ifdef HAVE_LCD_COLOR
+RB_WRAP(lcd_rgbpack)
+{
+    int r = luaL_checkint(L, 1);
+    int g = luaL_checkint(L, 2);
+    int b = luaL_checkint(L, 3);
+    int result = LCD_RGBPACK(r, g, b);
+    lua_pushinteger(L, result);
+    return 1;
+}
+
+RB_WRAP(lcd_rgbunpack)
+{
+    int rgb = luaL_checkint(L, 1);
+    lua_pushinteger(L, RGB_UNPACK_RED(rgb));
+    lua_pushinteger(L, RGB_UNPACK_GREEN(rgb));
+    lua_pushinteger(L, RGB_UNPACK_BLUE(rgb));
+    return 3;
+}
+#endif
+
+RB_WRAP(read_bmp_file)
+{
+    struct bitmap bm;
+    const char* filename = luaL_checkstring(L, 1);
+    bool dither = luaL_optboolean(L, 2, true);
+    bool transparent = luaL_optboolean(L, 3, false);
+    int format = FORMAT_NATIVE;
+
+    if(dither)
+        format |= FORMAT_DITHER;
+
+    if(transparent)
+        format |= FORMAT_TRANSPARENT;
+
+    int result = rb->read_bmp_file(filename, &bm, 0, format | FORMAT_RETURN_SIZE, NULL);
+
+    if(result > 0)
+    {
+        bm.data = (unsigned char*) rli_alloc(L, bm.width, bm.height);
+        if(rb->read_bmp_file(filename, &bm, result, format, NULL) < 0)
+        {
+            /* Error occured, drop newly allocated image from stack */
+            lua_pop(L, 1);
+            lua_pushnil(L);
+        }
+    }
+    else
+        lua_pushnil(L);
+
+    return 1;
+}
+
+#define R(NAME) {#NAME, rock_##NAME}
+const luaL_Reg rocklib_img[] =
+{
+    /* Graphics */
+#ifdef HAVE_LCD_BITMAP
+    R(lcd_framebuffer),
+    R(lcd_mono_bitmap_part),
+    R(lcd_mono_bitmap),
+#if LCD_DEPTH > 1
+    R(lcd_get_backdrop),
+    R(lcd_bitmap_part),
+    R(lcd_bitmap),
+#endif
+#if LCD_DEPTH == 16
+    R(lcd_bitmap_transparent_part),
+    R(lcd_bitmap_transparent),
+#endif
+#endif /*HAVE_LCD_BITMAP*/
+#ifdef HAVE_LCD_COLOR
+    R(lcd_rgbpack),
+    R(lcd_rgbunpack),
+#endif
+    R(read_bmp_file),
+    {"new_image", rli_new},
+
+    {NULL, NULL}
+};
+#undef  R
+