diff options
Diffstat (limited to 'nuttx/graphics/nxglib/fb/nxglib_filltrapezoid.c')
-rw-r--r-- | nuttx/graphics/nxglib/fb/nxglib_filltrapezoid.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/nuttx/graphics/nxglib/fb/nxglib_filltrapezoid.c b/nuttx/graphics/nxglib/fb/nxglib_filltrapezoid.c new file mode 100644 index 000000000..7623bf84f --- /dev/null +++ b/nuttx/graphics/nxglib/fb/nxglib_filltrapezoid.c @@ -0,0 +1,285 @@ +/**************************************************************************** + * graphics/nxglib/fb/nxglib_filltrapezoid.c + * + * Copyright (C) 2008-2012 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <gnutt@nuttx.org> + * + * 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 <stdint.h> +#include <fixedmath.h> + +#include <nuttx/fb.h> +#include <nuttx/nx/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. + * Clip the trapezoid to lie within a boundng box. This is useful for + * drawing complex shapes that can be broken into a set of trapezoids. + * + ****************************************************************************/ + +void NXGL_FUNCNAME(nxgl_filltrapezoid,NXGLIB_SUFFIX)( + FAR struct fb_planeinfo_s *pinfo, + FAR const struct nxgl_trapezoid_s *trap, + FAR const struct nxgl_rect_s *bounds, + NXGL_PIXEL_T color) +{ + unsigned int stride; + unsigned int width; + FAR uint8_t *dest; + FAR uint8_t *line; + int nrows; + b16_t x1; + b16_t x2; + nxgl_coord_t y1; + nxgl_coord_t y2; + b16_t dx1dy; + b16_t dx2dy; + +#if NXGLIB_BITSPERPIXEL < 8 + uint8_t mpixel = NXGL_MULTIPIXEL(color); + uint8_t mask; + int lnlen; +#endif + + /* 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; + + /* Calculate the number of rows to render */ + + y1 = trap->top.y; + y2 = trap->bot.y; + nrows = y2 - y1 + 1; + + /* Calculate the slope of the left and right side of the trapezoid */ + + if (nrows > 1) + { + dx1dy = b16divi((trap->bot.x1 - x1), nrows - 1); + dx2dy = b16divi((trap->bot.x2 - x2), nrows - 1); + } + else + { + /* The trapezoid is a run! Use the average width. */ + + x1 = (x1 + trap->bot.x1) >> 1; + x2 = (x2 + trap->bot.x2) >> 1; + dx1dy = 0; + dx2dy = 0; + } + + /* Perform vertical clipping */ + + if (y1 < bounds->pt1.y) + { + /* Is the entire trapezoid "above" the clipping window? */ + + if (y2 < bounds->pt1.y) + { + /* Yes.. then do nothing */ + + return; + } + + /* Calculate the x values for the new top run */ + + int dy = bounds->pt1.y - y1; + x1 += dy * dx1dy; + x2 += dy * dx2dy; + + /* Clip and re-calculate the number of rows to render */ + + y1 = bounds->pt1.y; + nrows = y2 - y1 + 1; + } + + if (y2 > bounds->pt2.y) + { + /* Is the entire trapezoid "below" the clipping window? */ + + if (y1 > bounds->pt2.y) + { + /* Yes.. then do nothing */ + + return; + } + + /* Clip and re-calculate the number of rows to render */ + + y2 = bounds->pt2.y; + nrows = y2 - y1 + 1; + } + + /* Get the address of the first byte on the first line */ + + line = pinfo->fbmem + y1 * stride ; + + /* 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 >= bounds->pt1.x && ix1 <= bounds->pt2.x) + { + /* Get a clipped copies of the starting and ending X positions. This + * clipped truncates "down" and gives the quantized pixel holding the + * fractional X position + */ + + ix1 = ngl_clipl(ix1, bounds->pt1.x); + ix2 = ngl_clipr(ix2, bounds->pt2.x); + + /* Get the run length for the clipped row */ + + width = ix2 - ix1 + 1; + +#if NXGLIB_BITSPERPIXEL < 8 + /* Handle masking of the fractional initial byte */ + +#ifdef CONFIG_NX_PACKEDMSFIRST + mask = (uint8_t)(0xff >> (8 - NXGL_REMAINDERX(ix1)); +#else + mask = (uint8_t)(0xff << (8 - NXGL_REMAINDERX(ix1))); +#endif + dest = line; + lnlen = width; + + if (lnlen > 1 && mask) + { + dest[0] = (dest[0] & ~mask) | (mpixel & mask); + mask = 0xff; + dest++; + lnlen--; + } + + /* Handle masking of the fractional final byte */ + +#ifdef CONFIG_NX_PACKEDMSFIRST + mask &= (uint8_t)(0xff << (8 - NXGL_REMAINDERX(ix2))); +#else + mask &= (uint8_t)(0xff >> (8 - NXGL_REMAINDERX(ix2))); +#endif + if (lnlen > 0 && mask) + { + dest[lnlen-1] = (dest[lnlen-1] & ~mask) | (mpixel & mask); + lnlen--; + } + + /* Handle all of the unmasked bytes in-between */ + + if (lnlen > 0) + { + NXGL_MEMSET(dest, (NXGL_PIXEL_T)color, lnlen); + } + +#else + /* Then draw the run from (line + ix1) to (line + ix2) */ + + dest = line + NXGL_SCALEX(ix1); + NXGL_MEMSET(dest, (NXGL_PIXEL_T)color, width); +#endif + } + + /* 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; + } +} |