Add more rasterizers

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@1316 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 167 insertions, 0 deletions

diff --git a/nuttx/graphics/nxglib/nxglib_filltrapezoid.c b/nuttx/graphics/nxglib/nxglib_filltrapezoid.c
new file mode 100644
index 000000000..f1f13a00f
--- /dev/null
+++ b/nuttx/graphics/nxglib/nxglib_filltrapezoid.c
@@ -0,0 +1,167 @@
+/****************************************************************************
+ * graphics/nxglib/nxglib_filltrapezoid.c
+ *
+ *   Copyright (C) 2008 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <fixedmath.h>
+#include <nuttx/fb.h>
+#include <nuttx/nxglib.h>
+
+#include "nxglib_bitblit.h"
+
+/****************************************************************************
+ * Pre-Processor Definitions
+ ****************************************************************************/
+
+#ifndef NXGLIB_SUFFIX
+#  error "NXGLIB_SUFFIX must be defined before including this header file"
+#endif
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nxglib_filltrapezoid_*bpp
+ *
+ * Descripton:
+ *   Fill a trapezoidal region in the framebuffer memory with a fixed color.
+ *   This is useful for drawing complex shape -- (most) complex shapes can be
+ *   broken into a set of trapezoids.
+ *
+ ****************************************************************************/
+
+void NXGL_FUNCNAME(nxglib_filltrapezoid,NXGLIB_SUFFIX)
+(FAR struct fb_videoinfo_s *vinfo, FAR struct fb_planeinfo_s *pinfo,
+ FAR const struct nxgl_trapezoid_s *trap, NXGL_PIXEL_T color)
+{
+  unsigned int stride;
+  ubyte *line;
+  int nrows;
+  b16_t x1;
+  b16_t x2;
+  b16_t dx1dy;
+  b16_t dx2dy;
+
+  /* Get the width of the framebuffer in bytes */
+
+  stride = pinfo->stride;
+
+  /* Get the top run position and the number of rows to draw */
+
+  x1     = trap->top.x1;
+  x2     = trap->top.x2;
+  nrows  = trap->bot.y - trap->top.y + 1;
+
+  /* Get the address of the first byte on the first line */
+
+  line   = pinfo->fbmem + trap->top.y * stride ;
+
+  /* Calculate the slope of the left and right side of the trapezoid */
+
+  dx1dy  = b16divi((trap->bot.x1 - x1), nrows);
+  dx2dy  = b16divi((trap->bot.x2 - x2), nrows);
+
+  /* Then fill the trapezoid line-by-line */
+
+  while (nrows--)
+    {
+      int ix1;
+      int ix2;
+
+      /* Handle the special case where the sides cross (as in an hourglass) */
+
+      if (x1 > x2)
+        {
+          b16_t tmp;
+          ngl_swap(x1, x2, tmp);
+          ngl_swap(dx1dy, dx2dy, tmp);
+        }
+
+      /* Convert the positions to integer */
+
+      ix1 = b16toi(x1);
+      ix2 = b16toi(x2);
+
+      /* Handle some corner cases where we draw nothing.  Otherwise, we will
+       * always draw at least one pixel.
+       */
+
+      if (x1 > x2 || ix2 < 0 || ix1 > vinfo->yres)
+        {
+          /* Get a clipped copies of the startingand ending X positions.  This
+           * clipped truncates "down" and gives the quantized pixel holding the
+           * fractional X position
+           */
+
+          ix1 = ngl_clipl(ix1, 0);
+          ix2 = ngl_clipr(ix2, vinfo->yres);
+
+          /* Then draw the run from (line + clipx1) to (line + clipx2) */
+
+          NXGL_MEMSET(line + NXGL_SCALEX(ix1), color, ix2 - ix1 + 1);
+        }
+
+      /* Move to the start of the next line */
+
+      line += stride;
+
+      /* Add the dx/dy value to get the run positions on the next row */
+
+      x1   += dx1dy;
+      x2   += dx2dy;
+    }
+}