/**************************************************************************** * graphics/nxglib/lcd/nxglib_filltrapezoid.c * * Copyright (C) 2010-2012 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #include #include #include #include #include "nxglib_bitblit.h" #include "nxglib_fillrun.h" /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #ifndef NXGLIB_SUFFIX # error "NXGLIB_SUFFIX must be defined before including this header file" #endif /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: nxglib_filltrapezoid_*bpp * * Description: * Fill a trapezoidal region in the LCD 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 lcd_planeinfo_s *pinfo, FAR const struct nxgl_trapezoid_s *trap, FAR const struct nxgl_rect_s *bounds, NXGL_PIXEL_T color) { unsigned int ncols; unsigned int topy; unsigned int boty; unsigned int row; unsigned int botw; b16_t topx1; b16_t topx2; b16_t botx1; b16_t botx2; b16_t dx1dy; b16_t dx2dy; int dy; int ix1; int ix2; /* Get the top run endpoints */ topx1 = trap->top.x1; topx2 = trap->top.x2; /* Calculate the number of rows to render */ topy = trap->top.y; boty = trap->bot.y; /* Get the bottom run endpoints */ botx1 = trap->bot.x1; botx2 = trap->bot.x2; /* Calculate the slope of the left and right side of the trapezoid */ dy = boty - topy; if (dy > 0) { dx1dy = b16divi((botx1 - topx1), dy); dx2dy = b16divi((botx2 - topx2), dy); } else { /* The trapezoid is a run! Use the average width. */ topx1 = (topx1 + botx1) >> 1; topx2 = (topx2 + botx2) >> 1; botx1 = topx1; botx2 = topx2; dx1dy = 0; dx2dy = 0; } /* Perform vertical clipping */ if (topy < bounds->pt1.y) { /* Is the entire trapezoid "above" the clipping window? */ if (boty < bounds->pt1.y) { /* Yes.. then do nothing */ return; } /* Calculate the x values for the new top run */ dy = bounds->pt1.y - topy; topx1 += dy * dx1dy; topx2 += dy * dx2dy; /* Clip the top row to render */ topy = bounds->pt1.y; } if (boty > bounds->pt2.y) { /* Is the entire trapezoid "below" the clipping window? */ if (topy > bounds->pt2.y) { /* Yes.. then do nothing */ return; } /* Calculate the x values for the new bottom run */ dy = boty - bounds->pt2.y; botx1 -= dy * dx1dy; botx2 -= dy * dx2dy; /* Clip the bottom row to render */ boty = bounds->pt2.y; } /* Handle the special case where the sides cross (as in an hourglass) */ if (botx1 > botx2) { b16_t tmp; ngl_swap(botx1, botx2, tmp); } /* Fill the run buffer for the maximum run that we will need */ ix1 = b16toi(topx1); ix1 = ngl_clipl(ix1, bounds->pt1.x); ix2 = b16toi(topx2); ix2 = ngl_clipr(ix2, bounds->pt2.x); ncols = ix2 - ix1 + 1; ix1 = b16toi(botx1); ix1 = ngl_clipl(ix1, bounds->pt1.x); ix2 = b16toi(botx2); ix2 = ngl_clipr(ix2, bounds->pt2.x); botw = ix2 - ix1 + 1; if (ncols < botw) { ncols = botw; } NXGL_FUNCNAME(nxgl_fillrun, NXGLIB_SUFFIX)((NXGLIB_RUNTYPE *)pinfo->buffer, color, ncols); /* Then fill the trapezoid row-by-row */ for (row = topy; row <= boty; row++) { /* Handle the special case where the sides cross (as in an hourglass) */ if (topx1 > topx2) { b16_t tmp; ngl_swap(topx1, topx2, tmp); ngl_swap(dx1dy, dx2dy, tmp); } /* Convert the positions to integer and get the run width, clipping to * fit within the bounding box. */ ix1 = b16toi(topx1); ix1 = ngl_clipl(ix1, bounds->pt1.x); ix2 = b16toi(topx2); ix2 = ngl_clipr(ix2, bounds->pt2.x); /* Handle some corner cases where we draw nothing. Otherwise, we will * always draw at least one pixel. */ if (ix1 <= ix2) { /* Then draw the run from ix1 to ix2 at row */ ncols = ix2 - ix1 + 1; pinfo->putrun(row, ix1, pinfo->buffer, ncols); } /* Add the dx/dy value to get the run positions on the next row */ topx1 += dx1dy; topx2 += dx2dy; } }