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Diffstat (limited to 'sys/gio/calcomp/ccpcseg.x')
| -rw-r--r-- | sys/gio/calcomp/ccpcseg.x | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/sys/gio/calcomp/ccpcseg.x b/sys/gio/calcomp/ccpcseg.x new file mode 100644 index 00000000..7b55adc7 --- /dev/null +++ b/sys/gio/calcomp/ccpcseg.x @@ -0,0 +1,207 @@ +# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc. + +include <gki.h> +include <gset.h> +include <mach.h> +include "ccp.h" + +# CCP_CALCSEG -- Calculate a contiguous line segment; used to return individual +# line segments under the various options of line type simulation. (Width is +# not simulated here). Each segment returned is actually drawable, guaranteeing +# constant-length dashes and gaps along the exact length of the input polyline. +# Normally called by ccp_polyline. + +procedure ccp_calcseg (p, npts, ltype, curpl_pt, segsize, xseg,yseg, nsegpts) + +short p[ARB] # points defining line +int npts # number of points, i.e., (x,y) pairs +int ltype # line type; CCP_CLEAR <= ltype <= CCP_DASHDOT +int curpl_pt # current polyline point; input and output +int segsize # current segment memory size +pointer xseg,yseg # plotter-unit contiguous line segment, output +int nsegpts # number of points in segment, output + +int i, j +real lastp_x, lastp_y, x, y, curseglen +bool toggle + +include "ccp.com" + +begin + if (curpl_pt == 1) { # always start line w/beginning of dash, etc. + lastp_x = XTRAN(p[1]) + lastp_y = YTRAN(p[2]) + curpl_pt = curpl_pt + 1 + toggle = false + } + + XSEG(1) = lastp_x + YSEG(1) = lastp_y + nsegpts = 1 + curseglen = 0.0 + + switch (ltype) { + case GL_CLEAR: + nsegpts = 0 + + case GL_DASHED: + # Return one contiguous polyline segment worth one dash: + call ccx_dash (p, npts, curpl_pt, curseglen, nsegpts, segsize, + xseg,yseg, lastp_x,lastp_y) + + # Now increment internal counters for gap width for next call + call ccx_gap (p, npts, curpl_pt, curseglen, g_dashlen + g_gaplen, + lastp_x,lastp_y) + + case GL_DOTTED: + # Since we already built one point, we need only the following gap: + call ccx_gap (p, npts, curpl_pt, curseglen, g_gaplen, + lastp_x,lastp_y) + + case GL_DOTDASH: + # Implement as dash/gap/dot/gap/: + if (toggle) { # build dot/gap/ + x = lastp_x #XTRAN(p[i]) + y = lastp_y #YTRAN(p[i+1]) + nsegpts = 0 + call ccx_addsegpt (x,y, xseg,yseg, nsegpts, segsize) + toggle = false + call ccx_gap (p, npts, curpl_pt, curseglen, g_gaplen, + lastp_x,lastp_y) + + } else { # build dash/gap/ + call ccx_dash (p, npts, curpl_pt, curseglen, nsegpts, + segsize, xseg,yseg, lastp_x,lastp_y) + call ccx_gap (p, npts, curpl_pt, curseglen, + g_dashlen + g_gaplen, lastp_x,lastp_y) + toggle = true + } + + default: # solid line + do i = curpl_pt, npts { + j = (i-1) * 2 + 1 + x = XTRAN(p[j]) + y = YTRAN(p[j+1]) + call ccx_addsegpt (x,y, xseg,yseg, nsegpts, segsize) + } + curpl_pt = npts + } +end + + +# CCX_DASH -- Do the actual work of building a dashed line segment (no gap) + +procedure ccx_dash (p, npts, curpl_pt, curseglen, cursegpt, segsize, + xseg,yseg, lastp_x,lastp_y) + +short p[ARB] # Input: points defining line +int npts # Input: number of points, i.e., (x,y) pairs +int curpl_pt # In/Output: current polyline point +real curseglen # Output: length of current simulated ltype unit (._) +int cursegpt # Output: index of current drawable point in segment +int segsize # In/Output: current segment size +pointer xseg,yseg # Output: plotter-units, contiguous line segment +real lastp_x,lastp_y # Output: last point in segment (visible or invisible) + +int i +real temppl_dis, x, y, delx, dely +real actual_dis, rem_dashlen + +include "ccp.com" + +begin + rem_dashlen = g_dashlen + + # Build up current "dash" (may be bent any number of times). + + while (curseglen + EPSILON < g_dashlen && curpl_pt <= npts) { + i = (curpl_pt-1) * 2 + 1 + x = XTRAN(p[i]) + y = YTRAN(p[i+1]) + temppl_dis = DIS(lastp_x, lastp_y, x, y) + if (temppl_dis >= EPSILON) { + actual_dis = min (temppl_dis, rem_dashlen) + rem_dashlen = rem_dashlen - actual_dis + + delx = x - lastp_x + dely = y - lastp_y + x = lastp_x + delx * actual_dis / temppl_dis + y = lastp_y + dely * actual_dis / temppl_dis + + call ccx_addsegpt (x,y, xseg,yseg, cursegpt, segsize) + curseglen = curseglen + actual_dis + lastp_x = XSEG(cursegpt) + lastp_y = YSEG(cursegpt) + } + if (curseglen + EPSILON < g_dashlen) + curpl_pt = curpl_pt + 1 + } +end + + +# CCX_GAP -- Do the actual work of building an invisible gap along original +# polyline. + +procedure ccx_gap (p, npts, curpl_pt, curseglen, matchlen, lastp_x,lastp_y) + +short p[ARB] # Input: points defining line +int npts # Input: number of points, i.e., (x,y) pairs +int curpl_pt # In/Output: current polyline point +real curseglen # In/Output: length of current simulated ltype unit (._) +real matchlen # Output: length to build curseglen up to +real lastp_x,lastp_y # Output: last point in segment (visible, invisible) + +int i +real x, y, delx, dely +real temppl_dis, actual_dis, rem_gaplen + +include "ccp.com" + +begin + rem_gaplen = g_gaplen + + # Build up current "gap" (may be bent any number of times). + + while ((curseglen + EPSILON < (matchlen)) && (curpl_pt <= npts)) { + i = (curpl_pt-1) * 2 + 1 + x = XTRAN(p[i]) + y = YTRAN(p[i+1]) + + temppl_dis = DIS(lastp_x, lastp_y, x, y) + if (temppl_dis >= EPSILON) { + actual_dis = min (temppl_dis, rem_gaplen) + rem_gaplen = rem_gaplen - actual_dis + + delx = x - lastp_x + dely = y - lastp_y + curseglen = curseglen + actual_dis + lastp_x = lastp_x + delx * actual_dis / temppl_dis + lastp_y = lastp_y + dely * actual_dis / temppl_dis + } + if (curseglen + EPSILON < matchlen) + curpl_pt = curpl_pt + 1 + } +end + + +# CCX_ADDSEGPT -- add a point to the segment structure; handle memory needs + +procedure ccx_addsegpt (x,y, xseg,yseg, cursegpt,segsize) + +real x,y # point to be added to output segment +pointer xseg,yseg # NDC-coord contiguous line segment, output +int cursegpt # index of current drawable point in segment +int segsize # current segment size + +begin + cursegpt = cursegpt + 1 + + if (cursegpt > segsize) { + segsize = segsize + SEGSIZE + call realloc (xseg, segsize, TY_REAL) + call realloc (yseg, segsize, TY_REAL) + } + + XSEG(cursegpt) = x + YSEG(cursegpt) = y +end |