Add a test of the circle rendering logic

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3911 42af7a65-404d-4744-a932-0658087f49c3

ChangeLog.txt

@@ -98,3 +98,5 @@
 
 6.9 2011-xx-xx Gregory Nutt <spudmonkey@racsa.co.cr>
 
+	* apps/examples/nxlines:  Extend the line drawing text to include drawing
+	  of circles.

examples/README.txt

@@ -424,8 +424,21 @@ examplex/nxlines
       depends on CONFIG_EXAMPLES_NXLINES_BPP.
     CONFIG_EXAMPLES_NXLINES_LINEWIDTH - Selects the width of the lines in
       pixels (default: 16)
-    CONFIG_EXAMPLES_NXLINES_LINECOLOR -- The color of the lines drawn in the
+    CONFIG_EXAMPLES_NXLINES_LINECOLOR -- The color of the central lines drawn
-      background window. Default depends on CONFIG_EXAMPLES_NXLINES_BPP.
+      in the background window. Default depends on CONFIG_EXAMPLES_NXLINES_BPP
+      (there really is no meaningful default).
+    CONFIG_EXAMPLES_NXLINES_BORDERWIDTH -- The width of the circular border
+      drawn in the background window. (default: 4).
+    CONFIG_EXAMPLES_NXLINES_BORDERCOLOR -- The color of the circular border
+      drawn in the background window. Default depends on CONFIG_EXAMPLES_NXLINES_BPP
+      (there really is no meaningful default).
+    CONFIG_EXAMPLES_NXLINES_CIRCLECOLOR -- The color of the circular region
+      filled in the background window. Default depends on CONFIG_EXAMPLES_NXLINES_BPP
+      (there really is no meaningful default).
+    CONFIG_EXAMPLES_NXLINES_BORDERCOLOR -- The color of the lines drawn in the
+      background window. Default depends on CONFIG_EXAMPLES_NXLINES_BPP (there
+      really is no meaningful default).
+
     CONFIG_EXAMPLES_NXLINES_BPP -- Pixels per pixel to use.  Valid options
       include 2, 4, 8, 16, 24, and 32.  Default is 16.
     CONFIG_EXAMPLES_NXLINES_EXTERNINIT - The driver for the graphics device on

examples/nxlines/nxlines.h

@@ -92,6 +92,30 @@
 #  endif
 #endif
 
+#ifndef CONFIG_EXAMPLES_NXLINES_BORDERWIDTH
+#  define CONFIG_EXAMPLES_NXLINES_BORDERWIDTH 16
+#endif
+
+#ifndef CONFIG_EXAMPLES_NXLINES_BORDERCOLOR
+#  if CONFIG_EXAMPLES_NXLINES_BPP == 24 || CONFIG_EXAMPLES_NXLINES_BPP == 32
+#    define CONFIG_EXAMPLES_NXLINES_BORDERCOLOR RGB24_YELLOW
+#  elif CONFIG_EXAMPLES_NXLINES_BPP == 16
+#    define CONFIG_EXAMPLES_NXLINES_BORDERCOLOR RGB16_YELLOW
+#  else
+#    define CONFIG_EXAMPLES_NXLINES_BORDERCOLOR RGB8_YELLOW
+#  endif
+#endif
+
+#ifndef CONFIG_EXAMPLES_NXLINES_CIRCLECOLOR
+#  if CONFIG_EXAMPLES_NXLINES_BPP == 24 || CONFIG_EXAMPLES_NXLINES_BPP == 32
+#    define CONFIG_EXAMPLES_NXLINES_CIRCLECOLOR RGB24_BEIGE
+#  elif CONFIG_EXAMPLES_NXLINES_BPP == 16
+#    define CONFIG_EXAMPLES_NXLINES_CIRCLECOLOR RGB16_BEIGE
+#  else
+#    define CONFIG_EXAMPLES_NXLINES_CIRCLECOLOR RGB8_YELLOW
+#  endif
+#endif
+
 /* Debug ********************************************************************/
 
 #ifdef CONFIG_CPP_HAVE_VARARGS

examples/nxlines/nxlines_bkgd.c

@@ -201,28 +201,79 @@ static void nxlines_kbdin(NXWINDOW hwnd, uint8_t nch, FAR const uint8_t *ch,
 
 void nxlines_test(NXWINDOW hwnd)
 {
+  struct nxgl_point_s center;
   struct nxgl_vector_s vector;
   struct nxgl_vector_s previous;
   nxgl_mxpixel_t color[CONFIG_NX_NPLANES];
-  nxgl_coord_t xcenter;
+  nxgl_coord_t maxradius;
-  nxgl_coord_t ycenter;
   nxgl_coord_t radius;
   nxgl_coord_t halfx;
   nxgl_coord_t halfy;
   b16_t angle;
   int ret;
 
-  /* Get the radius and center of the circle */
+  /* Get the maximum radius and center of the circle */
 
-  radius  = MIN(g_nxlines.yres, g_nxlines.xres) >> 1;
+  maxradius = MIN(g_nxlines.yres, g_nxlines.xres) >> 1;
-  xcenter = g_nxlines.xres >> 1;
+  center.x  = g_nxlines.xres >> 1;
-  ycenter = g_nxlines.yres >> 1;
+  center.y  = g_nxlines.yres >> 1;
+
+  /* Draw a circular background */
+
+  radius = maxradius - ((CONFIG_EXAMPLES_NXLINES_BORDERWIDTH+1)/2);
+  color[0] = CONFIG_EXAMPLES_NXLINES_CIRCLECOLOR;
+  ret = nx_fillcircle((NXWINDOW)hwnd, &center, radius, color);
+  if (ret < 0)
+    {
+      message("nxlines_test: nx_fillcircle failed: %d\n", ret);
+    }
+
+  /* Draw the circular border */
+
+  color[0] = CONFIG_EXAMPLES_NXLINES_BORDERCOLOR;
+  ret = nx_drawcircle((NXWINDOW)hwnd, &center, radius,
+                      CONFIG_EXAMPLES_NXLINES_BORDERWIDTH, color);
+  if (ret < 0)
+    {
+      message("nxlines_test: nx_fillcircle failed: %d\n", ret);
+    }
+
+  /* Back off the radius to account for the thickness of border line
+   * and with a big fudge factor that will (hopefully) prevent the corners
+   * of the lines from overwriting the border.  This is overly complicated
+   * here because we don't assume anything about the screen resolution or
+   * the borderwidth or the line thickness (and there are certainly some
+   * smarter ways to do this).
+   */
+
+  if (maxradius > (CONFIG_EXAMPLES_NXLINES_BORDERWIDTH + 80))
+    {
+      radius = maxradius - (CONFIG_EXAMPLES_NXLINES_BORDERWIDTH + 40);
+    }
+  else if (maxradius > (CONFIG_EXAMPLES_NXLINES_BORDERWIDTH + 60))
+    {
+      radius = maxradius - (CONFIG_EXAMPLES_NXLINES_BORDERWIDTH + 30);
+    }
+  else if (maxradius > (CONFIG_EXAMPLES_NXLINES_BORDERWIDTH + 40))
+    {
+      radius = maxradius - (CONFIG_EXAMPLES_NXLINES_BORDERWIDTH + 20);
+    }
+  else if (maxradius > (CONFIG_EXAMPLES_NXLINES_BORDERWIDTH + 20))
+    {
+      radius = maxradius - (CONFIG_EXAMPLES_NXLINES_BORDERWIDTH + 10);
+    }
+  else
+    {
+      radius = maxradius - CONFIG_EXAMPLES_NXLINES_BORDERWIDTH;
+    }
+
+  /* The loop, showing the line in various orientations */
 
   angle = 0;
-  previous.pt1.x = xcenter;
+  previous.pt1.x = center.x;
-  previous.pt1.y = ycenter;
+  previous.pt1.y = center.y;
-  previous.pt2.x = xcenter;
+  previous.pt2.x = center.x;
-  previous.pt2.y = ycenter;
+  previous.pt2.y = center.y;
 
   for (;;)
     {
@@ -231,17 +282,17 @@ void nxlines_test(NXWINDOW hwnd)
       halfx = b16toi(b16muli(b16sin(angle), radius));
       halfy = b16toi(b16muli(b16cos(angle), radius));
 
-       vector.pt1.x = xcenter + halfx;
+      vector.pt1.x = center.x + halfx;
-       vector.pt1.y = ycenter + halfy;
+      vector.pt1.y = center.y + halfy;
-       vector.pt2.x = xcenter - halfx;
+      vector.pt2.x = center.x - halfx;
-       vector.pt2.y = ycenter - halfy;
+      vector.pt2.y = center.y - halfy;
 
       message("Angle: %08x vector: (%d,%d)->(%d,%d)\n",
               angle, vector.pt1.x, vector.pt1.y, vector.pt2.x, vector.pt2.y);
 
-       /* Clear the previous line */
+      /* Clear the previous line by overwriting it with the circle color */
 
-       color[0] = CONFIG_EXAMPLES_NXLINES_BGCOLOR;
+      color[0] = CONFIG_EXAMPLES_NXLINES_CIRCLECOLOR;
       ret = nx_drawline((NXWINDOW)hwnd, &previous, CONFIG_EXAMPLES_NXLINES_LINEWIDTH, color);
       if (ret < 0)
         {