/**************************************************************************** * graphics/nxglib/fb/pwfb_filltrapezoid.c * * Copyright (C) 2019 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" /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Make sure that this file is used in the proper context */ #ifndef NXGLIB_SUFFIX # error "NXGLIB_SUFFIX must be defined before including this header file" #endif /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: pwfb_filltrapezoid*bpp * * Description: * 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(pwfb_filltrapezoid, NXGLIB_SUFFIX)( FAR struct nxbe_window_s *bwnd, 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 = bwnd->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 = (FAR uint8_t *)bwnd->fbmem + y1 * stride ; /* Then fill the trapezoid line-by-line */ while (nrows--) { #ifdef CONFIG_NX_ANTIALIASING b16_t frac; #endif 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 /* NXGLIB_BITSPERPIXEL < 8 */ /* Then draw the run from (line + ix1) to (line + ix2) */ dest = line + NXGL_SCALEX(ix1); #ifdef CONFIG_NX_ANTIALIASING /* Perform blending on the first pixel of the row */ frac = b16ONE - b16frac(x1); NXGL_BLEND(dest, (NXGL_PIXEL_T)color, frac); dest += NXGL_SCALEX(1); width--; if (width > 0) { /* Copy pixels between the first and last pixel of the row. */ if (width > 1) { NXGL_MEMSET(dest, (NXGL_PIXEL_T)color, width-1); } /* And blend the final pixel */ dest += NXGL_SCALEX(width-1); frac = b16frac(x2); NXGL_BLEND(dest, (NXGL_PIXEL_T)color, frac); } #else /* CONFIG_NX_ANTIALIASING */ NXGL_MEMSET(dest, (NXGL_PIXEL_T)color, width); #endif /* CONFIG_NX_ANTIALIASING */ #endif /* NXGLIB_BITSPERPIXEL < 8 */ } /* 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; } }