[GUI Engine] Add RTGUI as a GUI Engine

1 files changed, 1923 insertions, 0 deletions

diff --git a/components/gui/src/dc.c b/components/gui/src/dc.c
new file mode 100644
index 0000000000..59d0e7ec4a
--- /dev/null
+++ b/components/gui/src/dc.c
@@ -0,0 +1,1923 @@
+/*
+ * File      : dc.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006 - 2009, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2009-10-16     Bernard      first version
+ * 2010-09-20     richard      modified rtgui_dc_draw_round_rect
+ * 2010-09-27     Bernard      fix draw_mono_bmp issue
+ * 2011-04-25     Bernard      fix fill polygon issue, which found by loveic
+ */
+
+/* for sin/cos etc */
+#include <math.h>
+
+#include <rtgui/dc.h>
+#include <rtgui/dc_hw.h>
+#include <rtgui/dc_client.h>
+
+#include <rtgui/rtgui_system.h>
+#include <rtgui/rtgui_server.h>
+#include <rtgui/widgets/window.h>
+#include <rtgui/widgets/title.h>
+
+#include <string.h> /* for strlen */
+#include <stdlib.h> /* fir qsort  */
+
+static int _int_compare(const void *a, const void *b)
+{
+    return (*(const int *) a) - (*(const int *) b);
+}
+
+void rtgui_dc_destory(struct rtgui_dc *dc)
+{
+    if (dc == RT_NULL) return;
+
+    dc->engine->fini(dc);
+    rtgui_free(dc);
+}
+RTM_EXPORT(rtgui_dc_destory);
+
+void rtgui_dc_draw_line(struct rtgui_dc *dc, int x1, int y1, int x2, int y2)
+{
+    if (dc == RT_NULL) return;
+
+    if (y1 == y2)
+    {
+        rtgui_dc_draw_hline(dc, x1, x2, y1);
+    }
+    else if (x1 == x2)
+    {
+        rtgui_dc_draw_vline(dc, x1, y1, y2);
+    }
+    else
+    {
+        int dx, dy, sdx, sdy, dxabs, dyabs, x, y, px, py;
+        register rt_base_t i;
+        /* rtgui_rect_t rect; */
+
+        dx = x2 - x1;       /* the horizontal distance of the line */
+        dy = y2 - y1;       /* the vertical distance of the line */
+
+#define rtgui_sgn(x) ((x<0)?-1:((x>0)?1:0)) /* macro to return the sign of a number */
+
+        dxabs = _UI_ABS(dx);
+        dyabs = _UI_ABS(dy);
+        sdx = rtgui_sgn(dx);
+        sdy = rtgui_sgn(dy);
+        x = dyabs >> 1;
+        y = dxabs >> 1;
+        px = x1;
+        py = y1;
+
+        if (dxabs >= dyabs) /* the line is more horizontal than vertical */
+        {
+            for (i = 0; i < dxabs; i++)
+            {
+                y += dyabs;
+                if (y >= dxabs)
+                {
+                    y -= dxabs;
+                    py += sdy;
+                }
+                px += sdx;
+
+                /* draw this point */
+                rtgui_dc_draw_point(dc, px, py);
+            }
+        }
+        else                /* the line is more vertical than horizontal */
+        {
+            for (i = 0; i < dyabs; i++)
+            {
+                x += dxabs;
+                if (x >= dyabs)
+                {
+                    x -= dyabs;
+                    px += sdx;
+                }
+                py += sdy;
+
+                /* draw this point */
+                rtgui_dc_draw_point(dc, px, py);
+            }
+        }
+    }
+}
+RTM_EXPORT(rtgui_dc_draw_line);
+
+void rtgui_dc_draw_horizontal_line(struct rtgui_dc *dc, int x1, int x2, int y)
+{
+    rtgui_color_t color;
+
+    if (dc == RT_NULL) return ;
+
+    /* save old color */
+    color = RTGUI_DC_FC(dc);
+
+    RTGUI_DC_FC(dc) = dark_grey;
+    rtgui_dc_draw_hline(dc, x1, x2, y);
+
+    y ++;
+
+    RTGUI_DC_FC(dc) = high_light;
+    rtgui_dc_draw_hline(dc, x1, x2, y);
+
+    /* restore color */
+    RTGUI_DC_FC(dc) = color;
+}
+RTM_EXPORT(rtgui_dc_draw_horizontal_line);
+
+void rtgui_dc_draw_vertical_line(struct rtgui_dc *dc, int x, int y1, int y2)
+{
+    rtgui_color_t color;
+
+    if (dc == RT_NULL) return ;
+
+    /* save old color */
+    color = RTGUI_DC_FC(dc);
+
+    RTGUI_DC_FC(dc) = dark_grey;
+    rtgui_dc_draw_vline(dc, x, y1, y2);
+
+    x ++;
+
+    RTGUI_DC_FC(dc) = high_light;
+    rtgui_dc_draw_vline(dc, x, y1, y2);
+
+    /* restore color */
+    RTGUI_DC_FC(dc) = color;
+}
+RTM_EXPORT(rtgui_dc_draw_vertical_line);
+
+void rtgui_dc_draw_rect(struct rtgui_dc *dc, struct rtgui_rect *rect)
+{
+    rtgui_dc_draw_hline(dc, rect->x1, rect->x2, rect->y1);
+    rtgui_dc_draw_hline(dc, rect->x1, rect->x2, rect->y2 - 1);
+
+    rtgui_dc_draw_vline(dc, rect->x1, rect->y1, rect->y2);
+    rtgui_dc_draw_vline(dc, rect->x2 - 1, rect->y1, rect->y2);
+}
+RTM_EXPORT(rtgui_dc_draw_rect);
+
+void rtgui_dc_fill_rect_forecolor(struct rtgui_dc *dc, struct rtgui_rect *rect)
+{
+    rtgui_color_t save_color;
+    /*save the background color of dc*/
+    save_color = RTGUI_DC_BC(dc);
+    /*set the background color to fore color*/
+    RTGUI_DC_BC(dc) = RTGUI_DC_FC(dc);
+    dc->engine->fill_rect(dc, rect);
+    /*restore the background color of dc*/
+    RTGUI_DC_BC(dc) = save_color;
+}
+RTM_EXPORT(rtgui_dc_fill_rect_forecolor);
+
+void rtgui_dc_draw_round_rect(struct rtgui_dc *dc, struct rtgui_rect *rect, int r)
+{
+    RT_ASSERT(((rect->x2 - rect->x1) / 2 >= r) && ((rect->y2 - rect->y1) / 2 >= r));
+
+    if (r < 0)
+    {
+        return;
+    }
+
+    if (r == 0)
+    {
+        rtgui_dc_draw_rect(dc, rect);
+        return;
+    }
+
+    if (((rect->x2 - rect->x1) / 2 >= r) && ((rect->y2 - rect->y1) / 2 >= r))
+    {
+        rtgui_dc_draw_arc(dc, rect->x1 + r, rect->y1 + r, r, 180, 270);
+        rtgui_dc_draw_arc(dc, rect->x2 - r, rect->y1 + r, r, 270, 360);
+        rtgui_dc_draw_arc(dc, rect->x1 + r, rect->y2 - r, r, 90,  180);
+        rtgui_dc_draw_arc(dc, rect->x2 - r, rect->y2 - r, r, 0,   90);
+
+        rtgui_dc_draw_hline(dc, rect->x1 + r, rect->x2 - r, rect->y1);
+        rtgui_dc_draw_hline(dc, rect->x1 + r, rect->x2 - r, rect->y2);
+        rtgui_dc_draw_vline(dc, rect->x1, rect->y1 + r, rect->y2 - r);
+        rtgui_dc_draw_vline(dc, rect->x2, rect->y1 + r, rect->y2 - r);
+    }
+}
+RTM_EXPORT(rtgui_dc_draw_round_rect);
+
+void rtgui_dc_fill_round_rect(struct rtgui_dc *dc, struct rtgui_rect *rect, int r)
+{
+    struct rtgui_rect rect_temp;
+
+    RT_ASSERT(((rect->x2 - rect->x1) / 2 >= r) && ((rect->y2 - rect->y1) / 2 >= r));
+
+    if (((rect->x2 - rect->x1) / 2 >= r) && ((rect->y2 - rect->y1) / 2 >= r))
+    {
+        rect_temp.x1 = rect->x1 + r;
+        rect_temp.y1 = rect->y1;
+        rect_temp.x2 = rect->x2 - r;
+        rect_temp.y2 = rect->y2;
+        rtgui_dc_fill_rect_forecolor(dc, &rect_temp);//fill rect with foreground
+
+        rect_temp.x1 = rect->x1;
+        rect_temp.y1 = rect->y1 + r;
+        rect_temp.x2 = rect->x1 + r;
+        rect_temp.y2 = rect->y2 - r;
+        rtgui_dc_fill_rect_forecolor(dc, &rect_temp);//fill rect with foreground
+
+        rect_temp.x1 = rect->x2 - r;
+        rect_temp.y1 = rect->y1 + r;
+        rect_temp.x2 = rect->x2;
+        rect_temp.y2 = rect->y2 - r;
+        rtgui_dc_fill_rect_forecolor(dc, &rect_temp);//fill rect with foreground
+
+        rtgui_dc_fill_circle(dc, rect->x1 + r, rect->y1 + r, r);
+        rtgui_dc_fill_circle(dc, rect->x2 - r, rect->y2 - r, r);
+        rtgui_dc_fill_circle(dc, rect->x2 - r, rect->y1 + r, r);
+        rtgui_dc_fill_circle(dc, rect->x1 + r, rect->y2 - r, r);
+    }
+}
+RTM_EXPORT(rtgui_dc_fill_round_rect);
+
+void rtgui_dc_draw_shaded_rect(struct rtgui_dc *dc, rtgui_rect_t *rect,
+                               rtgui_color_t c1, rtgui_color_t c2)
+{
+    RT_ASSERT(dc != RT_NULL);
+
+    RTGUI_DC_FC(dc) = c1;
+    rtgui_dc_draw_vline(dc, rect->x1, rect->y1, rect->y2);
+    rtgui_dc_draw_hline(dc, rect->x1 + 1, rect->x2, rect->y1);
+
+    RTGUI_DC_FC(dc) = c2;
+    rtgui_dc_draw_vline(dc, rect->x2 - 1, rect->y1, rect->y2);
+    rtgui_dc_draw_hline(dc, rect->x1, rect->x2, rect->y2 - 1);
+}
+RTM_EXPORT(rtgui_dc_draw_shaded_rect);
+
+void rtgui_dc_fill_gradient_rectv(struct rtgui_dc *dc, rtgui_rect_t *rect,
+                                  rtgui_color_t c1, rtgui_color_t c2)
+{
+    int y, step;
+    rtgui_color_t fc;
+
+    RT_ASSERT(dc != RT_NULL);
+    RT_ASSERT(rect != RT_NULL);
+
+    step = rtgui_rect_height(*rect);
+    fc = RTGUI_DC_FC(dc);
+
+    for (y = rect->y1; y < rect->y2; y++)
+    {
+        RTGUI_DC_FC(dc) = RTGUI_ARGB(((int)RTGUI_RGB_A(c2) - RTGUI_RGB_A(c1)) * (y - rect->y1) / step + RTGUI_RGB_A(c1),
+                                     ((int)RTGUI_RGB_R(c2) - RTGUI_RGB_R(c1)) * (y - rect->y1) / step + RTGUI_RGB_R(c1),
+                                     ((int)RTGUI_RGB_G(c2) - RTGUI_RGB_G(c1)) * (y - rect->y1) / step + RTGUI_RGB_G(c1),
+                                     ((int)RTGUI_RGB_B(c2) - RTGUI_RGB_B(c1)) * (y - rect->y1) / step + RTGUI_RGB_B(c1));
+        rtgui_dc_draw_hline(dc, rect->x1, rect->x2, y);
+    }
+
+    RTGUI_DC_FC(dc) = fc;
+}
+RTM_EXPORT(rtgui_dc_fill_gradient_rectv);
+
+void rtgui_dc_draw_focus_rect(struct rtgui_dc *dc, rtgui_rect_t *rect)
+{
+    int x, y;
+
+    for (x = rect->x1; x < rect->x2 - 1; x += 2)
+    {
+        rtgui_dc_draw_point(dc, x, rect->y1);
+        rtgui_dc_draw_point(dc, x, rect->y2 - 1);
+    }
+
+    for (y = rect->y1; y < rect->y2; y += 2)
+    {
+        rtgui_dc_draw_point(dc, rect->x1, y);
+        rtgui_dc_draw_point(dc, rect->x2 - 1, y);
+    }
+}
+RTM_EXPORT(rtgui_dc_draw_focus_rect);
+
+void rtgui_dc_draw_text(struct rtgui_dc *dc, const char *text, struct rtgui_rect *rect)
+{
+    rt_uint32_t len;
+    struct rtgui_font *font;
+    struct rtgui_rect text_rect;
+
+    RT_ASSERT(dc != RT_NULL);
+
+    font = RTGUI_DC_FONT(dc);
+    if (font == RT_NULL)
+    {
+        /* use system default font */
+        font = rtgui_font_default();
+    }
+
+    /* text align */
+    rtgui_font_get_metrics(font, text, &text_rect);
+    rtgui_rect_moveto_align(rect, &text_rect, RTGUI_DC_TEXTALIGN(dc));
+
+    len = strlen((const char *)text);
+    rtgui_font_draw(font, dc, text, len, &text_rect);
+}
+RTM_EXPORT(rtgui_dc_draw_text);
+
+void rtgui_dc_draw_text_stroke(struct rtgui_dc *dc, const char *text, struct rtgui_rect *rect,
+                               rtgui_color_t color_stroke, rtgui_color_t color_core)
+{
+    int x, y;
+    rtgui_rect_t r;
+    rtgui_color_t fc;
+
+    RT_ASSERT(dc != RT_NULL);
+
+    fc = RTGUI_DC_FC(dc);
+    RTGUI_DC_FC(dc) = color_stroke;
+    for (x = -1; x < 2; x++)
+    {
+        for (y = -1; y < 2; y++)
+        {
+            r = *rect;
+            rtgui_rect_moveto(&r, x, y);
+            rtgui_dc_draw_text(dc, text, &r);
+        }
+    }
+    RTGUI_DC_FC(dc) = color_core;
+    rtgui_dc_draw_text(dc, text, rect);
+    RTGUI_DC_FC(dc) = fc;
+}
+RTM_EXPORT(rtgui_dc_draw_text_stroke);
+
+/*
+ * draw a monochrome color bitmap data
+ */
+void rtgui_dc_draw_mono_bmp(struct rtgui_dc *dc, int x, int y, int w, int h, const rt_uint8_t *data)
+{
+    int i, j, k;
+
+    /* get word bytes */
+    w = (w + 7) / 8;
+
+    /* draw mono bitmap data */
+    for (i = 0; i < h; i ++)
+        for (j = 0; j < w; j++)
+            for (k = 0; k < 8; k++)
+                if (((data[i * w + j] >> (7 - k)) & 0x01) != 0)
+                    rtgui_dc_draw_point(dc, x + 8 * j + k, y + i);
+}
+RTM_EXPORT(rtgui_dc_draw_mono_bmp);
+
+void rtgui_dc_draw_byte(struct rtgui_dc *dc, int x, int y, int h, const rt_uint8_t *data)
+{
+    rtgui_dc_draw_mono_bmp(dc, x, y, 8, h, data);
+}
+RTM_EXPORT(rtgui_dc_draw_byte);
+
+void rtgui_dc_draw_word(struct rtgui_dc *dc, int x, int y, int h, const rt_uint8_t *data)
+{
+    rtgui_dc_draw_mono_bmp(dc, x, y, 16, h, data);
+}
+RTM_EXPORT(rtgui_dc_draw_word);
+
+void rtgui_dc_draw_border(struct rtgui_dc *dc, rtgui_rect_t *rect, int flag)
+{
+    rtgui_rect_t r;
+    rtgui_color_t color;
+
+    if (dc == RT_NULL) return ;
+
+    /* save old color */
+    color = RTGUI_DC_FC(dc);
+
+    r = *rect;
+    switch (flag)
+    {
+    case RTGUI_BORDER_RAISE:
+        rtgui_dc_draw_shaded_rect(dc, &r, high_light, black);
+        rtgui_rect_inflate(&r, -1);
+        rtgui_dc_draw_shaded_rect(dc, &r, light_grey, dark_grey);
+        break;
+
+    case RTGUI_BORDER_SUNKEN:
+        rtgui_dc_draw_shaded_rect(dc, &r, dark_grey, high_light);
+        rtgui_rect_inflate(&r, -1);
+        rtgui_dc_draw_shaded_rect(dc, &r, black, light_grey);
+        break;
+
+    case RTGUI_BORDER_BOX:
+        rtgui_dc_draw_shaded_rect(dc, &r, dark_grey, high_light);
+        rtgui_rect_inflate(&r, -1);
+        rtgui_dc_draw_shaded_rect(dc, &r, high_light, dark_grey);
+        break;
+
+    case RTGUI_BORDER_STATIC:
+        rtgui_dc_draw_shaded_rect(dc, &r, dark_grey, high_light);
+        break;
+
+    case RTGUI_BORDER_EXTRA:
+        RTGUI_DC_FC(dc) = light_grey;
+        rtgui_dc_draw_rect(dc, &r);
+        break;
+
+    case RTGUI_BORDER_SIMPLE:
+        RTGUI_DC_FC(dc) = black;
+        rtgui_dc_draw_rect(dc, &r);
+        break;
+
+    default:
+        break;
+    }
+
+    /* restore color */
+    RTGUI_DC_FC(dc) = color;
+}
+RTM_EXPORT(rtgui_dc_draw_border);
+
+void rtgui_dc_draw_polygon(struct rtgui_dc *dc, const int *vx, const int *vy, int count)
+{
+    int i;
+    const int *x1, *y1, *x2, *y2;
+
+    /*
+     * Sanity check
+     */
+    if (count < 3) return;
+
+    /*
+     * Pointer setup
+     */
+    x1 = x2 = vx;
+    y1 = y2 = vy;
+    x2++;
+    y2++;
+
+    /*
+     * Draw
+     */
+    for (i = 1; i < count; i++)
+    {
+        rtgui_dc_draw_line(dc, *x1, *y1, *x2, *y2);
+        x1 = x2;
+        y1 = y2;
+        x2++;
+        y2++;
+    }
+    rtgui_dc_draw_line(dc, *x1, *y1, *vx, *vy);
+}
+RTM_EXPORT(rtgui_dc_draw_polygon);
+
+void rtgui_dc_fill_polygon(struct rtgui_dc *dc, const int *vx, const int *vy, int count)
+{
+    int i;
+    int y, xa, xb;
+    int miny, maxy;
+    int x1, y1;
+    int x2, y2;
+    int ind1, ind2;
+    int ints;
+    int *poly_ints = RT_NULL;
+
+    /*
+     * Sanity check number of edges
+     */
+    if (count < 3) return;
+
+    /*
+     * Allocate temp array, only grow array
+     */
+    poly_ints = (int *) rtgui_malloc(sizeof(int) * count);
+    if (poly_ints == RT_NULL) return ; /* no memory, failed */
+
+    /*
+     * Determine Y maximal
+     */
+    miny = vy[0];
+    maxy = vy[0];
+    for (i = 1; (i < count); i++)
+    {
+        if (vy[i] < miny) miny = vy[i];
+        else if (vy[i] > maxy) maxy = vy[i];
+    }
+
+    /*
+     * Draw, scanning y
+     */
+    for (y = miny; (y <= maxy); y++)
+    {
+        ints = 0;
+        for (i = 0; (i < count); i++)
+        {
+            if (!i)
+            {
+                ind1 = count - 1;
+                ind2 = 0;
+            }
+            else
+            {
+                ind1 = i - 1;
+                ind2 = i;
+            }
+            y1 = vy[ind1];
+            y2 = vy[ind2];
+            if (y1 < y2)
+            {
+                x1 = vx[ind1];
+                x2 = vx[ind2];
+            }
+            else if (y1 > y2)
+            {
+                y2 = vy[ind1];
+                y1 = vy[ind2];
+                x2 = vx[ind1];
+                x1 = vx[ind2];
+            }
+            else
+            {
+                continue;
+            }
+
+            if (((y >= y1) && (y < y2)) || ((y == maxy) && (y > y1) && (y <= y2)))
+            {
+                poly_ints[ints++] = ((65536 * (y - y1)) / (y2 - y1)) * (x2 - x1) + (65536 * x1);
+            }
+        }
+
+        qsort(poly_ints, ints, sizeof(int), _int_compare);
+
+        for (i = 0; (i < ints); i += 2)
+        {
+            xa = poly_ints[i] + 1;
+            xa = (xa >> 16) + ((xa & 32768) >> 15);
+            xb = poly_ints[i + 1] - 1;
+            xb = (xb >> 16) + ((xb & 32768) >> 15);
+            rtgui_dc_draw_hline(dc, xa, xb, y);
+        }
+    }
+
+    /* release memory */
+    rtgui_free(poly_ints);
+}
+RTM_EXPORT(rtgui_dc_fill_polygon);
+
+void rtgui_dc_draw_circle(struct rtgui_dc *dc, int x, int y, int r)
+{
+    rtgui_dc_draw_ellipse(dc, x, y, r, r);
+}
+RTM_EXPORT(rtgui_dc_draw_circle);
+
+enum
+{
+    QUARTER_BTM,
+    QUARTER_BTM_LEFT,
+    QUARTER_BTM_RIGHT,
+    QUARTER_TOP,
+    QUARTER_TOP_LEFT,
+    QUARTER_TOP_RIGHT,
+    QUARTER_FULL,
+};
+
+static void _fill_quarter_circle(struct rtgui_dc *dc,
+                                 rt_int16_t ox, rt_int16_t oy,
+                                 rt_int16_t rad, int quadrant)
+{
+    /* Midpoint circle algorithm. */
+    int dk, x, y;
+
+    dk = 1 - rad;
+    x = 0;
+    y = rad;
+
+    while (x <= y)
+    {
+        switch (quadrant)
+        {
+        case QUARTER_BTM:
+            rtgui_dc_draw_hline(dc, ox - x, ox + x, oy + y);
+            rtgui_dc_draw_hline(dc, ox - y, ox + y, oy + x);
+            break;
+        case QUARTER_BTM_LEFT:
+            rtgui_dc_draw_hline(dc, ox, ox + x, oy + y);
+            rtgui_dc_draw_hline(dc, ox, ox + y, oy + x);
+            break;
+        case QUARTER_BTM_RIGHT:
+            rtgui_dc_draw_hline(dc, ox, ox - x, oy + y);
+            rtgui_dc_draw_hline(dc, ox, ox - y, oy + x);
+            break;
+        case QUARTER_TOP_RIGHT:
+            rtgui_dc_draw_hline(dc, ox, ox - x, oy - y);
+            rtgui_dc_draw_hline(dc, ox, ox - y, oy - x);
+            break;
+        case QUARTER_TOP_LEFT:
+            rtgui_dc_draw_hline(dc, ox, ox + x, oy - y);
+            rtgui_dc_draw_hline(dc, ox, ox + y, oy - x);
+            break;
+        case QUARTER_TOP:
+            rtgui_dc_draw_hline(dc, ox - x, ox + x, oy - y);
+            rtgui_dc_draw_hline(dc, ox - y, ox + y, oy - x);
+            break;
+        case QUARTER_FULL:
+            rtgui_dc_draw_hline(dc, ox - x, ox + x, oy + y);
+            rtgui_dc_draw_hline(dc, ox - y, ox + y, oy + x);
+            rtgui_dc_draw_hline(dc, ox - x, ox + x, oy - y);
+            rtgui_dc_draw_hline(dc, ox - y, ox + y, oy - x);
+            break;
+        default:
+            RT_ASSERT(0);
+        };
+
+        if (dk > 0)
+        {
+            y--;
+            dk += 2 * (x - y) + 5;
+        }
+        else
+        {
+            dk += 2 * x + 3;
+        }
+        x++;
+    }
+}
+
+void rtgui_dc_fill_circle(struct rtgui_dc *dc, rt_int16_t x, rt_int16_t y, rt_int16_t r)
+{
+    /*
+     * Sanity check radius
+     */
+    if (r < 0)
+        return;
+
+    /*
+     * Special case for r=0 - draw a point
+     */
+    if (r == 0)
+    {
+        rtgui_dc_draw_point(dc, x, y);
+        return;
+    }
+
+    _fill_quarter_circle(dc, x, y, r, QUARTER_FULL);
+}
+RTM_EXPORT(rtgui_dc_fill_circle);
+
+void rtgui_dc_draw_arc(struct rtgui_dc *dc, rt_int16_t x, rt_int16_t y, rt_int16_t r, rt_int16_t start, rt_int16_t end)
+{
+    rt_int16_t cx = 0;
+    rt_int16_t cy = r;
+    rt_int16_t df = 1 - r;
+    rt_int16_t d_e = 3;
+    rt_int16_t d_se = -2 * r + 5;
+    rt_int16_t xpcx, xmcx, xpcy, xmcy;
+    rt_int16_t ypcy, ymcy, ypcx, ymcx;
+    rt_uint8_t drawoct;
+    int startoct, endoct, oct, stopval_start, stopval_end;
+    double temp;
+
+    stopval_start = 0;
+    stopval_end = 0;
+    temp = 0;
+
+    /* Sanity check radius */
+    if (r < 0) return ;
+    /* Special case for r=0 - draw a point */
+    if (r == 0)
+    {
+        rtgui_dc_draw_point(dc, x, y);
+        return;
+    }
+
+    /*
+     * Draw arc
+     */
+
+    // Octant labelling
+    //
+    //  \ 5 | 6 /
+    //   \  |  /
+    //  4 \ | / 7
+    //     \|/
+    //------+------ +x
+    //     /|\
+    //  3 / | \ 0
+    //   /  |  \
+    //  / 2 | 1 \
+    //      +y
+
+    drawoct = 0; // 0x00000000
+    // whether or not to keep drawing a given octant.
+    // For example: 0x00111100 means we're drawing in octants 2-5
+
+    // 0 <= start & end < 360; note that sometimes start > end - if so, arc goes back through 0.
+    while (start < 0) start += 360;
+    while (end < 0) end += 360;
+    /* Fixup angles */
+    start = start % 360;
+    end = end % 360;
+
+
+    // now, we find which octants we're drawing in.
+    startoct = start / 45;
+    endoct = end / 45;
+    oct = startoct - 1; // we increment as first step in loop
+
+    //stopval_start, stopval_end; // what values of cx to stop at.
+    do
+    {
+        oct = (oct + 1) % 8;
+
+        if (oct == startoct)
+        {
+            // need to compute stopval_start for this octant.  Look at picture above if this is unclear
+            switch (oct)
+            {
+            case 0:
+            case 3:
+                temp = sin(start * M_PI / 180);
+                break;
+            case 1:
+            case 6:
+                temp = cos(start * M_PI / 180);
+                break;
+            case 2:
+            case 5:
+                temp = -cos(start * M_PI / 180);
+                break;
+            case 4:
+            case 7:
+                temp = -sin(start * M_PI / 180);
+                break;
+            }
+            temp *= r;
+            stopval_start = (int)temp; // always round down.
+            // This isn't arbitrary, but requires graph paper to explain well.
+            // The basic idea is that we're always changing drawoct after we draw, so we
+            // stop immediately after we render the last sensible pixel at x = ((int)temp).
+
+            // and whether to draw in this octant initially
+            if (oct % 2) drawoct |= (1 << oct); // this is basically like saying drawoct[oct] = true, if drawoct were a bool array
+            else         drawoct &= 255 - (1 << oct); // this is basically like saying drawoct[oct] = false
+        }
+
+        if (oct == endoct)
+        {
+            // need to compute stopval_end for this octant
+            switch (oct)
+            {
+            case 0:
+            case 3:
+                temp = sin(end * M_PI / 180);
+                break;
+            case 1:
+            case 6:
+                temp = cos(end * M_PI / 180);
+                break;
+            case 2:
+            case 5:
+                temp = -cos(end * M_PI / 180);
+                break;
+            case 4:
+            case 7:
+                temp = -sin(end * M_PI / 180);
+                break;
+            }
+            temp *= r;
+            stopval_end = (int)temp;
+
+            // and whether to draw in this octant initially
+            if (startoct == endoct)
+            {
+                // note:      we start drawing, stop, then start again in this case
+                // otherwise: we only draw in this octant, so initialize it to false, it will get set back to true
+                if (start > end)
+                {
+                    // unfortunately, if we're in the same octant and need to draw over the whole circle,
+                    // we need to set the rest to true, because the while loop will end at the bottom.
+                    drawoct = 255;
+                }
+                else
+                {
+                    drawoct &= 255 - (1 << oct);
+                }
+            }
+            else if (oct % 2) drawoct &= 255 - (1 << oct);
+            else              drawoct |= (1 << oct);
+        }
+        else if (oct != startoct)     // already verified that it's != endoct
+        {
+            drawoct |= (1 << oct); // draw this entire segment
+        }
+    }
+    while (oct != endoct);
+
+    // so now we have what octants to draw and when to draw them.  all that's left is the actual raster code.
+    do
+    {
+        ypcy = y + cy;
+        ymcy = y - cy;
+        if (cx > 0)
+        {
+            xpcx = x + cx;
+            xmcx = x - cx;
+            // always check if we're drawing a certain octant before adding a pixel to that octant.
+            if (drawoct & 4)  rtgui_dc_draw_point(dc, xmcx, ypcy); // drawoct & 4 = 22; drawoct[2]
+            if (drawoct & 2)  rtgui_dc_draw_point(dc, xpcx, ypcy);
+            if (drawoct & 32) rtgui_dc_draw_point(dc, xmcx, ymcy);
+            if (drawoct & 64) rtgui_dc_draw_point(dc, xpcx, ymcy);
+        }
+        else
+        {
+            if (drawoct & 6)  rtgui_dc_draw_point(dc, x, ypcy); // 4 + 2; drawoct[2] || drawoct[1]
+            if (drawoct & 96) rtgui_dc_draw_point(dc, x, ymcy); // 32 + 64
+        }
+
+        xpcy = x + cy;
+        xmcy = x - cy;
+        if (cx > 0 && cx != cy)
+        {
+            ypcx = y + cx;
+            ymcx = y - cx;
+            if (drawoct & 8)   rtgui_dc_draw_point(dc, xmcy, ypcx);
+            if (drawoct & 1)   rtgui_dc_draw_point(dc, xpcy, ypcx);
+            if (drawoct & 16)  rtgui_dc_draw_point(dc, xmcy, ymcx);
+            if (drawoct & 128) rtgui_dc_draw_point(dc, xpcy, ymcx);
+        }
+        else if (cx == 0)
+        {
+            if (drawoct & 24)  rtgui_dc_draw_point(dc, xmcy, y); // 8 + 16
+            if (drawoct & 129) rtgui_dc_draw_point(dc, xpcy, y); // 1 + 128
+        }
+
+        /*
+         * Update whether we're drawing an octant
+         */
+        if (stopval_start == cx)
+        {
+            // works like an on-off switch because start & end may be in the same octant.
+            if (drawoct & (1 << startoct)) drawoct &= 255 - (1 << startoct);
+            else drawoct |= (1 << startoct);
+        }
+        if (stopval_end == cx)
+        {
+            if (drawoct & (1 << endoct)) drawoct &= 255 - (1 << endoct);
+            else drawoct |= (1 << endoct);
+        }
+
+        /*
+         * Update pixels
+         */
+        if (df < 0)
+        {
+            df += d_e;
+            d_e += 2;
+            d_se += 2;
+        }
+        else
+        {
+            df += d_se;
+            d_e += 2;
+            d_se += 4;
+            cy--;
+        }
+
+        cx++;
+    }
+    while (cx <= cy);
+}
+RTM_EXPORT(rtgui_dc_draw_arc);
+
+void rtgui_dc_draw_annulus(struct rtgui_dc *dc, rt_int16_t x, rt_int16_t y, rt_int16_t r1, rt_int16_t r2, rt_int16_t start, rt_int16_t end)
+{
+    rt_int16_t start_x, start_y;
+    rt_int16_t end_x, end_y;
+    double temp;
+    rt_int16_t temp_val = 0;
+
+    /* Sanity check radius */
+    if ((r1 < 0) || (r2 < 0)) return ;
+    /* Special case for r=0 - draw a point */
+    if ((r1 == 0) && (r2 == 0))
+    {
+        rtgui_dc_draw_point(dc, x, y);
+        return;
+    }
+
+    while (start < 0) start += 360;
+    while (end < 0) end += 360;
+
+    rtgui_dc_draw_arc(dc, x, y, r1, start, end);
+    rtgui_dc_draw_arc(dc, x, y, r2, start, end);
+
+    temp     = cos(start * M_PI / 180);
+    temp_val = (int)(temp * r1);
+    start_x  = x + temp_val;
+    temp_val = (int)(temp * r2);
+    end_x    = x + temp_val;
+
+    temp     = sin(start * M_PI / 180);
+    temp_val = (int)(temp * r1);
+    start_y  = y + temp_val;
+    temp_val = (int)(temp * r2);
+    end_y    = y + temp_val;
+
+    rtgui_dc_draw_line(dc, start_x, start_y, end_x, end_y);
+
+    temp     = cos(end * M_PI / 180);
+    temp_val = (int)(temp * r1);
+    start_x  = x + temp_val;
+    temp_val = (int)(temp * r2);
+    end_x    = x + temp_val;
+
+    temp     = sin(end * M_PI / 180);
+    temp_val = (int)(temp * r1);
+    start_y  = y + temp_val;
+    temp_val = (int)(temp * r2);
+    end_y    = y + temp_val;
+
+    rtgui_dc_draw_line(dc, start_x, start_y, end_x, end_y);
+}
+RTM_EXPORT(rtgui_dc_draw_annulus);
+
+void rtgui_dc_draw_ellipse(struct rtgui_dc *dc, rt_int16_t x, rt_int16_t y, rt_int16_t rx, rt_int16_t ry)
+{
+    int ix, iy;
+    int h, i, j, k;
+    int oh, oi, oj, ok;
+    int xmh, xph, ypk, ymk;
+    int xmi, xpi, ymj, ypj;
+    int xmj, xpj, ymi, ypi;
+    int xmk, xpk, ymh, yph;
+
+    /*
+     * Sanity check radii
+     */
+    if ((rx < 0) || (ry < 0))  return;
+
+    /*
+     * Special case for rx=0 - draw a vline
+     */
+    if (rx == 0)
+    {
+        rtgui_dc_draw_vline(dc, x, y - ry, y + ry);
+        return;
+    }
+
+    /*
+     * Special case for ry=0 - draw a hline
+     */
+    if (ry == 0)
+    {
+        rtgui_dc_draw_hline(dc, x - rx, x + rx, y);
+        return;
+    }
+
+    /*
+     * Init vars
+     */
+    oh = oi = oj = ok = 0xFFFF;
+
+    if (rx > ry)
+    {
+        ix = 0;
+        iy = rx * 64;
+
+        do
+        {
+            h = (ix + 32) >> 6;
+            i = (iy + 32) >> 6;
+            j = (h * ry) / rx;
+            k = (i * ry) / rx;
+
+            if (((ok != k) && (oj != k)) || ((oj != j) && (ok != j)) || (k != j))
+            {
+                xph = x + h;
+                xmh = x - h;
+                if (k > 0)
+                {
+                    ypk = y + k;
+                    ymk = y - k;
+                    rtgui_dc_draw_point(dc, xmh, ypk);
+                    rtgui_dc_draw_point(dc, xph, ypk);
+                    rtgui_dc_draw_point(dc, xmh, ymk);
+                    rtgui_dc_draw_point(dc, xph, ymk);
+                }
+                else
+                {
+                    rtgui_dc_draw_point(dc, xmh, y);
+                    rtgui_dc_draw_point(dc, xph, y);
+                }
+                ok = k;
+                xpi = x + i;
+                xmi = x - i;
+                if (j > 0)
+                {
+                    ypj = y + j;
+                    ymj = y - j;
+                    rtgui_dc_draw_point(dc, xmi, ypj);
+                    rtgui_dc_draw_point(dc, xpi, ypj);
+                    rtgui_dc_draw_point(dc, xmi, ymj);
+                    rtgui_dc_draw_point(dc, xpi, ymj);
+                }
+                else
+                {
+                    rtgui_dc_draw_point(dc, xmi, y);
+                    rtgui_dc_draw_point(dc, xpi, y);
+                }
+                oj = j;
+            }
+
+            ix = ix + iy / rx;
+            iy = iy - ix / rx;
+        }
+        while (i > h);
+    }
+    else
+    {
+        ix = 0;
+        iy = ry * 64;
+
+        do
+        {
+            h = (ix + 32) >> 6;
+            i = (iy + 32) >> 6;
+            j = (h * rx) / ry;
+            k = (i * rx) / ry;
+
+            if (((oi != i) && (oh != i)) || ((oh != h) && (oi != h) && (i != h)))
+            {
+                xmj = x - j;
+                xpj = x + j;
+                if (i > 0)
+                {
+                    ypi = y + i;
+                    ymi = y - i;
+                    rtgui_dc_draw_point(dc, xmj, ypi);
+                    rtgui_dc_draw_point(dc, xpj, ypi);
+                    rtgui_dc_draw_point(dc, xmj, ymi);
+                    rtgui_dc_draw_point(dc, xpj, ymi);
+                }
+                else
+                {
+                    rtgui_dc_draw_point(dc, xmj, y);
+                    rtgui_dc_draw_point(dc, xpj, y);
+                }
+                oi = i;
+                xmk = x - k;
+                xpk = x + k;
+                if (h > 0)
+                {
+                    yph = y + h;
+                    ymh = y - h;
+                    rtgui_dc_draw_point(dc, xmk, yph);
+                    rtgui_dc_draw_point(dc, xpk, yph);
+                    rtgui_dc_draw_point(dc, xmk, ymh);
+                    rtgui_dc_draw_point(dc, xpk, ymh);
+                }
+                else
+                {
+                    rtgui_dc_draw_point(dc, xmk, y);
+                    rtgui_dc_draw_point(dc, xpk, y);
+                }
+                oh = h;
+            }
+
+            ix = ix + iy / ry;
+            iy = iy - ix / ry;
+        }
+        while (i > h);
+    }
+}
+RTM_EXPORT(rtgui_dc_draw_ellipse);
+
+void rtgui_dc_fill_ellipse(struct rtgui_dc *dc, rt_int16_t x, rt_int16_t y, rt_int16_t rx, rt_int16_t ry)
+{
+    int ix, iy;
+    int h, i, j, k;
+    int oh, oi, oj, ok;
+    int xmh, xph;
+    int xmi, xpi;
+    int xmj, xpj;
+    int xmk, xpk;
+
+    /*
+     * Special case for rx=0 - draw a vline
+     */
+    if (rx == 0)
+    {
+        rtgui_dc_draw_vline(dc, x, y - ry, y + ry);
+        return;
+    }
+
+    /* special case for ry=0 - draw a hline  */
+    if (ry == 0)
+    {
+        rtgui_dc_draw_hline(dc, x - rx, x + rx, y);
+        return;
+    }
+
+    /*
+     * Init vars
+     */
+    oh = oi = oj = ok = 0xFFFF;
+
+    /*
+     * Draw
+     */
+    if (rx > ry)
+    {
+        ix = 0;
+        iy = rx * 64;
+
+        do
+        {
+            h = (ix + 32) >> 6;
+            i = (iy + 32) >> 6;
+            j = (h * ry) / rx;
+            k = (i * ry) / rx;
+
+            if ((ok != k) && (oj != k))
+            {
+                xph = x + h;
+                xmh = x - h;
+                if (k > 0)
+                {
+                    rtgui_dc_draw_hline(dc, xmh, xph, y + k);
+                    rtgui_dc_draw_hline(dc, xmh, xph, y - k);
+                }
+                else
+                {
+                    rtgui_dc_draw_hline(dc, xmh, xph, y);
+                }
+                ok = k;
+            }
+            if ((oj != j) && (ok != j) && (k != j))
+            {
+                xmi = x - i;
+                xpi = x + i;
+                if (j > 0)
+                {
+                    rtgui_dc_draw_hline(dc, xmi, xpi, y + j);
+                    rtgui_dc_draw_hline(dc, xmi, xpi, y - j);
+                }
+                else
+                {
+                    rtgui_dc_draw_hline(dc, xmi, xpi, y);
+                }
+                oj = j;
+            }
+
+            ix = ix + iy / rx;
+            iy = iy - ix / rx;
+
+        }
+        while (i > h);
+    }
+    else
+    {
+        ix = 0;
+        iy = ry * 64;
+
+        do
+        {
+            h = (ix + 32) >> 6;
+            i = (iy + 32) >> 6;
+            j = (h * rx) / ry;
+            k = (i * rx) / ry;
+
+            if ((oi != i) && (oh != i))
+            {
+                xmj = x - j;
+                xpj = x + j;
+                if (i > 0)
+                {
+                    rtgui_dc_draw_hline(dc, xmj, xpj, y + i);
+                    rtgui_dc_draw_hline(dc, xmj, xpj, y - i);
+                }
+                else
+                {
+                    rtgui_dc_draw_hline(dc, xmj, xpj, y);
+                }
+                oi = i;
+            }
+            if ((oh != h) && (oi != h) && (i != h))
+            {
+                xmk = x - k;
+                xpk = x + k;
+                if (h > 0)
+                {
+                    rtgui_dc_draw_hline(dc, xmk, xpk, y + h);
+                    rtgui_dc_draw_hline(dc, xmk, xpk, y - h);
+                }
+                else
+                {
+                    rtgui_dc_draw_hline(dc, xmk, xpk, y);
+                }
+                oh = h;
+            }
+            ix = ix + iy / ry;
+            iy = iy - ix / ry;
+        }
+        while (i > h);
+    }
+}
+RTM_EXPORT(rtgui_dc_fill_ellipse);
+
+void rtgui_dc_draw_pie(struct rtgui_dc *dc, rt_int16_t x, rt_int16_t y, rt_int16_t rad, rt_int16_t start, rt_int16_t end)
+{
+    double angle, start_angle, end_angle;
+    double deltaAngle;
+    double dr;
+    int numpoints, i;
+    int *vx, *vy;
+
+    /* Sanity check radii */
+    if (rad < 0) return ;
+
+    /*
+     * Fixup angles
+     */
+    start = start % 360;
+    end = end % 360;
+
+    /*
+     * Special case for rad=0 - draw a point
+     */
+    if (rad == 0)
+    {
+        rtgui_dc_draw_point(dc, x, y);
+        return;
+    }
+
+    /*
+     * Variable setup
+     */
+    dr = (double) rad;
+    deltaAngle = 3.0 / dr;
+    start_angle = (double) start * (2.0 * M_PI / 360.0);
+    end_angle = (double) end * (2.0 * M_PI / 360.0);
+    if (start > end)
+    {
+        end_angle += (2.0 * M_PI);
+    }
+
+    /* We will always have at least 2 points */
+    numpoints = 2;
+
+    /* Count points (rather than calculating it) */
+    angle = start_angle;
+    while (angle < end_angle)
+    {
+        angle += deltaAngle;
+        numpoints++;
+    }
+
+    /* Allocate combined vertex array */
+    vx = vy = (int *) rtgui_malloc(2 * sizeof(int) * numpoints);
+    if (vx == RT_NULL) return ;
+
+    /* Update point to start of vy */
+    vy += numpoints;
+
+    /* Center */
+    vx[0] = x;
+    vy[0] = y;
+
+    /* First vertex */
+    angle = start_angle;
+    vx[1] = x + (int)(dr * cos(angle));
+    vy[1] = y + (int)(dr * sin(angle));
+
+    if (numpoints < 3)
+    {
+        rtgui_dc_draw_line(dc, vx[0], vy[0], vx[1], vy[1]);
+    }
+    else
+    {
+        /* Calculate other vertices */
+        i = 2;
+        angle = start_angle;
+        while (angle < end_angle)
+        {
+            angle += deltaAngle;
+            if (angle > end_angle)
+            {
+                angle = end_angle;
+            }
+            vx[i] = x + (int)(dr * cos(angle));
+            vy[i] = y + (int)(dr * sin(angle));
+            i++;
+        }
+
+        /* Draw */
+        rtgui_dc_draw_polygon(dc, vx, vy, numpoints);
+    }
+
+    /* Free combined vertex array */
+    rtgui_free(vx);
+    return;
+}
+RTM_EXPORT(rtgui_dc_draw_pie);
+
+// Octant labelling
+//
+//  \ 5 | 6 /
+//   \  |  /
+//  4 \ | / 7
+//     \|/
+//------+------ +x
+//     /|\
+//  3 / | \ 0
+//   /  |  \
+//  / 2 | 1 \
+//      +y
+static void _draw_octant(struct rtgui_dc *dc,
+                         rt_int16_t ox, rt_int16_t oy,
+                         rt_int16_t y1, rt_int16_t y2, rt_int16_t x, int oct)
+{
+    switch (oct % 8)
+    {
+    case 0:
+        rtgui_dc_draw_line(dc, ox +  x, oy + y1, ox +  x, oy + y2);
+        break;
+    case 1:
+        /* Ugly hack to get the edge right. */
+        y2 += 1;
+        y1 += 1;
+        x -= 1;
+        rtgui_dc_draw_line(dc, ox + y1, oy +  x, ox + y2, oy +  x);
+        break;
+    case 2:
+        y2 -= 1;
+        y1 -= 1;
+        x -= 1;
+        rtgui_dc_draw_line(dc, ox - y2, oy +  x, ox - y1, oy +  x);
+        break;
+    case 3:
+        x -= 1;
+        rtgui_dc_draw_line(dc, ox -  x, oy + y1, ox -  x, oy + y2);
+        break;
+    case 4:
+        x -= 1;
+        rtgui_dc_draw_line(dc, ox -  x, oy - y2, ox -  x, oy - y1);
+        break;
+    case 5:
+        y2 -= 1;
+        y1 -= 1;
+        rtgui_dc_draw_line(dc, ox - y2, oy -  x, ox - y1, oy -  x);
+        break;
+    case 6:
+        y2 += 1;
+        y1 += 1;
+        rtgui_dc_draw_line(dc, ox + y1, oy -  x, ox + y2, oy -  x);
+        break;
+    case 7:
+        rtgui_dc_draw_line(dc, ox +  x, oy - y2, ox +  x, oy - y1);
+        break;
+    };
+}
+
+static void _fill_small_pie(struct rtgui_dc *dc,
+                            rt_int16_t ox, rt_int16_t oy,
+                            rt_int16_t rad, rt_int16_t start, rt_int16_t end,
+                            int oct)
+{
+    /* Midpoint circle algorithm. */
+    int dk, x, y;
+    /* Start X, end X, */
+    rt_int16_t sx, ex, ty, my;
+    enum {ST_NONE, ST_ARC, ST_TRI} st;
+
+    RT_ASSERT(0 <= start && start <= 45);
+    RT_ASSERT(0 <= end && end <= 45);
+    if (start == end)
+        return;
+    RT_ASSERT(start < end);
+    RT_ASSERT(rad > 0);
+
+    /* cos(90 - start) == sin(start) */
+    sx = rad * sin(start * M_PI / 180);
+    ex = rad * sin(end * M_PI / 180);
+
+    dk = 1 - rad;
+    x = 0;
+    y = rad;
+
+    st = ST_NONE;
+    my = ex;
+    while (x <= y)
+    {
+        rt_int16_t lx;
+
+        if (x < sx)
+        {
+        }
+        else if (x == sx)
+        {
+            /* Start point. */
+            st = ST_ARC;
+            ty = y;
+        }
+        else if (x <= ex)
+        {
+            /* Between the pie. */
+            RT_ASSERT(st == ST_ARC);
+        }
+        else /* x > ex */
+        {
+            /* End. */
+            st = ST_TRI;
+            my = y;
+            break;
+        }
+
+        /* Drawing. */
+        if (st == ST_ARC)
+        {
+            lx = y * sx / ty;
+            /* Change from math coordinate to plot coordinate. */
+            _draw_octant(dc, ox, oy, lx, x, y, oct);
+        }
+
+        /* Midpoint increment. */
+        if (dk > 0)
+        {
+            y--;
+            dk += 2 * (x - y) + 5;
+        }
+        else
+        {
+            dk += 2 * x + 3;
+        }
+        x++;
+    }
+    /* Draw bottom part. */
+    for (; y >= 0; y--)
+    {
+        rt_int16_t lx, rx;
+
+        lx = y * sx / ty;
+        rx = y * ex / my;
+
+        _draw_octant(dc, ox, oy, lx, rx, y, oct);
+    }
+}
+
+void rtgui_dc_fill_pie(struct rtgui_dc *dc,
+                       rt_int16_t x, rt_int16_t y, rt_int16_t rad,
+                       rt_int16_t start, rt_int16_t end)
+{
+    /* Sanity check radii */
+    if (rad < 0)
+        return;
+    if (rad == 0)
+    {
+        rtgui_dc_draw_point(dc, x, y);
+        return;
+    }
+
+    if (end - start >= 360)
+    {
+        rtgui_dc_fill_circle(dc, x, y, rad);
+        return;
+    }
+    if (start == end)
+        return;
+
+    /*
+     * Fixup angles
+     */
+    while (start < 0)
+    {
+        start += 360;
+        end   += 360;
+    }
+    while (start >= 360)
+    {
+        start -= 360;
+        end   -= 360;
+    }
+
+    if (end < start)
+        end += 360;
+
+    while (start / 45 != end / 45)
+    {
+        /* The start and end are not in the same piece. */
+        if ((start / 45) % 2)
+        {
+            _fill_small_pie(dc, x, y, rad,
+                            0, 45 - start % 45, start / 45);
+            start += 45 - start % 45;
+        }
+        else
+        {
+            _fill_small_pie(dc, x, y, rad,
+                            start % 45, 45, start / 45);
+            start += 45 - start % 45;
+        }
+    }
+    if ((start / 45) % 2)
+    {
+        _fill_small_pie(dc, x, y, rad,
+                        90 - end % 90, 90 - start % 90, start / 45);
+    }
+    else
+    {
+        _fill_small_pie(dc, x, y, rad,
+                        start % 45, end % 45, start / 45);
+    }
+
+    return;
+}
+RTM_EXPORT(rtgui_dc_fill_pie);
+
+/*
+ * set gc of dc
+ */
+void rtgui_dc_set_gc(struct rtgui_dc *dc, rtgui_gc_t *gc)
+{
+    RT_ASSERT(dc != RT_NULL);
+
+    switch (dc->type)
+    {
+    case RTGUI_DC_CLIENT:
+    {
+        rtgui_widget_t *owner;
+        /* get owner */
+        owner = RTGUI_CONTAINER_OF(dc, struct rtgui_widget, dc_type);
+        owner->gc = *gc;
+        break;
+    }
+    case RTGUI_DC_HW:
+    {
+        struct rtgui_dc_hw *dc_hw;
+
+        dc_hw = (struct rtgui_dc_hw *) dc;
+        RT_ASSERT(dc_hw->owner != RT_NULL);
+        dc_hw->owner->gc = *gc;
+        break;
+    }
+    case RTGUI_DC_BUFFER:
+    {
+        struct rtgui_dc_buffer *dc_buffer;
+
+        dc_buffer = (struct rtgui_dc_buffer *)dc;
+        dc_buffer->gc = *gc;
+        break;
+    }
+    }
+}
+RTM_EXPORT(rtgui_dc_set_gc);
+
+/*
+ * get gc of dc
+ */
+rtgui_gc_t *rtgui_dc_get_gc(struct rtgui_dc *dc)
+{
+    rtgui_gc_t *gc = RT_NULL;
+
+    RT_ASSERT(dc != RT_NULL);
+
+    switch (dc->type)
+    {
+    case RTGUI_DC_CLIENT:
+    {
+        rtgui_widget_t *owner;
+        /* get owner */
+        owner = RTGUI_CONTAINER_OF(dc, struct rtgui_widget, dc_type);
+        gc = &owner->gc;
+        break;
+    }
+    case RTGUI_DC_HW:
+    {
+        struct rtgui_dc_hw *dc_hw;
+
+        dc_hw = (struct rtgui_dc_hw *) dc;
+        RT_ASSERT(dc_hw->owner != RT_NULL);
+        gc = &dc_hw->owner->gc;
+        break;
+    }
+    case RTGUI_DC_BUFFER:
+    {
+        struct rtgui_dc_buffer *dc_buffer;
+
+        dc_buffer = (struct rtgui_dc_buffer *)dc;
+        gc = &dc_buffer->gc;
+        break;
+    }
+    }
+
+    return gc;
+}
+RTM_EXPORT(rtgui_dc_get_gc);
+
+/*
+ * get visible status of dc
+ */
+rt_bool_t rtgui_dc_get_visible(struct rtgui_dc *dc)
+{
+    rt_bool_t result = RT_TRUE;
+
+    RT_ASSERT(dc != RT_NULL);
+
+    if (rtgui_graphic_driver_is_vmode())
+        return RT_TRUE;
+
+    switch (dc->type)
+    {
+    case RTGUI_DC_CLIENT:
+    {
+        rtgui_widget_t *owner;
+        /* get owner */
+        owner = RTGUI_CONTAINER_OF(dc, struct rtgui_widget, dc_type);
+        if (!RTGUI_WIDGET_IS_DC_VISIBLE(owner)) result = RT_FALSE;
+        break;
+    }
+    case RTGUI_DC_HW:
+    {
+        struct rtgui_dc_hw *dc_hw;
+
+        dc_hw = (struct rtgui_dc_hw *) dc;
+        if (!RTGUI_WIDGET_IS_DC_VISIBLE(dc_hw->owner)) result = RT_FALSE;
+        break;
+    }
+
+    default:
+        /* use default value */
+        break;
+    }
+
+    return result;
+}
+RTM_EXPORT(rtgui_dc_get_visible);
+
+/*
+ * get rect of dc
+ */
+void rtgui_dc_get_rect(struct rtgui_dc *dc, rtgui_rect_t *rect)
+{
+    RT_ASSERT(dc != RT_NULL);
+
+    switch (dc->type)
+    {
+    case RTGUI_DC_CLIENT:
+    {
+        rtgui_widget_t *owner;
+        /* get owner */
+        owner = RTGUI_CONTAINER_OF(dc, struct rtgui_widget, dc_type);
+        /* we should return the clipped rectangular information */
+        rect->x1 = owner->clip.extents.x1 - owner->extent.x1;
+        rect->y1 = owner->clip.extents.y1 - owner->extent.y1;
+        rect->x2 = rect->x1 + owner->clip.extents.x2 - owner->clip.extents.x1;
+        rect->y2 = rect->y1 + owner->clip.extents.y2 - owner->clip.extents.y1;
+        // rtgui_widget_get_rect(owner, rect);
+        break;
+    }
+    case RTGUI_DC_HW:
+    {
+        rtgui_widget_t *owner;
+        struct rtgui_dc_hw *dc_hw;
+
+        dc_hw = (struct rtgui_dc_hw *) dc;
+        owner = dc_hw->owner;
+        rtgui_widget_get_rect(owner, rect);
+        break;
+    }
+    case RTGUI_DC_BUFFER:
+    {
+        struct rtgui_dc_buffer *dc_buffer;
+
+        dc_buffer = (struct rtgui_dc_buffer *)dc;
+        rtgui_rect_init(rect, 0, 0, dc_buffer->width, dc_buffer->height);
+        break;
+    }
+    }
+
+    return;
+}
+RTM_EXPORT(rtgui_dc_get_rect);
+
+rt_uint8_t rtgui_dc_get_pixel_format(struct rtgui_dc *dc)
+{
+    rt_uint8_t pixel_fmt;
+
+    RT_ASSERT(dc != RT_NULL);
+
+    switch (dc->type)
+    {
+    case RTGUI_DC_CLIENT:
+    case RTGUI_DC_HW:
+    {
+        struct rtgui_graphic_driver *hw_driver;
+
+        hw_driver = rtgui_graphic_driver_get_default();
+        pixel_fmt = hw_driver->pixel_format;
+        break;
+    }
+    case RTGUI_DC_BUFFER:
+    {
+        struct rtgui_dc_buffer *dc_buffer;
+
+        dc_buffer = (struct rtgui_dc_buffer *)dc;
+        pixel_fmt = dc_buffer->pixel_format;
+        break;
+    }
+    default:
+        RT_ASSERT(0);
+    }
+
+    return pixel_fmt;
+}
+RTM_EXPORT(rtgui_dc_get_pixel_format);
+
+void rtgui_dc_logic_to_device(struct rtgui_dc *dc, struct rtgui_point *point)
+{
+    switch (dc->type)
+    {
+    case RTGUI_DC_CLIENT:
+    {
+        rtgui_widget_t *owner;
+        /* get owner */
+        owner = RTGUI_CONTAINER_OF(dc, struct rtgui_widget, dc_type);
+        point->x += owner->extent.x1;
+        point->y += owner->extent.y1;
+        break;
+    }
+    case RTGUI_DC_HW:
+    {
+        rtgui_widget_t *owner;
+        struct rtgui_dc_hw *dc_hw;
+
+        dc_hw = (struct rtgui_dc_hw *) dc;
+        owner = dc_hw->owner;
+        point->x += owner->extent.x1;
+        point->y += owner->extent.y1;
+        break;
+    }
+
+    case RTGUI_DC_BUFFER: /* no conversion */
+        break;
+    }
+}
+RTM_EXPORT(rtgui_dc_logic_to_device);
+
+void rtgui_dc_rect_to_device(struct rtgui_dc *dc, struct rtgui_rect *rect)
+{
+    switch (dc->type)
+    {
+    case RTGUI_DC_CLIENT:
+    {
+        rtgui_widget_t *owner;
+        /* get owner */
+        owner = RTGUI_CONTAINER_OF(dc, struct rtgui_widget, dc_type);
+
+        rtgui_rect_moveto(rect, owner->extent.x1, owner->extent.y1);
+        break;
+    }
+    case RTGUI_DC_HW:
+    {
+        rtgui_widget_t *owner;
+        struct rtgui_dc_hw *dc_hw;
+
+        dc_hw = (struct rtgui_dc_hw *) dc;
+        owner = dc_hw->owner;
+        rtgui_rect_moveto(rect, owner->extent.x1, owner->extent.y1);
+        break;
+    }
+
+    case RTGUI_DC_BUFFER: /* no conversion */
+        break;
+    }
+}
+RTM_EXPORT(rtgui_dc_rect_to_device);
+
+extern struct rt_mutex cursor_mutex;
+extern void rtgui_mouse_show_cursor(void);
+extern void rtgui_mouse_hide_cursor(void);
+
+struct rtgui_dc *rtgui_dc_begin_drawing(rtgui_widget_t *owner)
+{
+    struct rtgui_dc *dc;
+    struct rtgui_widget *widget;
+    struct rtgui_win *win;
+
+    RT_ASSERT(owner != RT_NULL);
+
+    win = owner->toplevel;
+    if (win == RT_NULL)
+        return RT_NULL;
+
+    if (!(win->flag & RTGUI_WIN_FLAG_ACTIVATE) &&
+            (win->outer_clip.extents.x1 == win->outer_clip.extents.x2 ||
+             win->outer_clip.extents.y1 == win->outer_clip.extents.y2))
+        return RT_NULL;
+
+    /* increase drawing count */
+    win->drawing ++;
+
+    /* always drawing on the virtual mode */
+    if (rtgui_graphic_driver_is_vmode() == RT_FALSE)
+    {
+        /* set the initial visible as true */
+        RTGUI_WIDGET_DC_SET_VISIBLE(owner);
+
+        /* check the visible of widget */
+        widget = owner;
+        while (widget != RT_NULL)
+        {
+            if (RTGUI_WIDGET_IS_HIDE(widget))
+            {
+                RTGUI_WIDGET_DC_SET_UNVISIBLE(owner);
+                win->drawing --;
+                return RT_NULL;
+            }
+            widget = widget->parent;
+        }
+    }
+
+    rtgui_screen_lock(RT_WAITING_FOREVER);
+
+    /* create client or hardware DC */
+    if ((rtgui_region_is_flat(&owner->clip) == RT_EOK) &&
+            rtgui_rect_is_equal(&(owner->extent), &(owner->clip.extents)) == RT_EOK)
+        dc = rtgui_dc_hw_create(owner);
+    else
+        dc = rtgui_dc_client_create(owner);
+
+    if (dc == RT_NULL)
+    {
+        /* restore drawing counter */
+        win->drawing--;
+        rtgui_screen_unlock();
+    }
+    else if (win->drawing == 1 && rtgui_graphic_driver_is_vmode() == RT_FALSE)
+    {
+#ifdef RTGUI_USING_MOUSE_CURSOR
+        rt_mutex_take(&cursor_mutex, RT_WAITING_FOREVER);
+        rtgui_mouse_hide_cursor();
+#endif
+
+        if (! RTGUI_IS_WINTITLE(win))
+        {
+            /* send draw begin to server */
+            struct rtgui_event_update_begin eupdate;
+            RTGUI_EVENT_UPDATE_BEGIN_INIT(&(eupdate));
+            eupdate.rect = RTGUI_WIDGET(win)->extent;
+
+            rtgui_server_post_event((struct rtgui_event *)&eupdate, sizeof(eupdate));
+        }
+    }
+
+    return dc;
+}
+RTM_EXPORT(rtgui_dc_begin_drawing);
+
+void rtgui_dc_end_drawing(struct rtgui_dc *dc)
+{
+    struct rtgui_widget *owner;
+    struct rtgui_win *win;
+
+    RT_ASSERT(dc != RT_NULL);
+
+    /* get owner */
+    if (dc->type == RTGUI_DC_CLIENT)
+        owner = RTGUI_CONTAINER_OF(dc, struct rtgui_widget, dc_type);
+    else if (dc->type == RTGUI_DC_HW)
+        owner = ((struct rtgui_dc_hw *)dc)->owner;
+    else return ; /* bad DC type */
+    /* get window */
+    win = owner->toplevel;
+
+    /* decrease drawing counter */
+    win->drawing --;
+    if (win->drawing == 0 && rtgui_graphic_driver_is_vmode() == RT_FALSE)
+    {
+#ifdef RTGUI_USING_MOUSE_CURSOR
+        rt_mutex_release(&cursor_mutex);
+        /* show cursor */
+        rtgui_mouse_show_cursor();
+#endif
+
+        if (RTGUI_IS_WINTITLE(win))
+        {
+            /* update screen */
+            rtgui_graphic_driver_screen_update(rtgui_graphic_driver_get_default(),
+                                               &(owner->extent));
+        }
+        else
+        {
+            /* send to server for window update */
+            struct rtgui_event_update_end eupdate;
+            RTGUI_EVENT_UPDATE_END_INIT(&(eupdate));
+            eupdate.rect = owner->extent;
+
+            rtgui_server_post_event((struct rtgui_event *)&eupdate, sizeof(eupdate));
+        }
+    }
+
+    dc->engine->fini(dc);
+    rtgui_screen_unlock();
+}
+RTM_EXPORT(rtgui_dc_end_drawing);
+