diff options
Diffstat (limited to 'lib/libppmd.c')
| -rw-r--r-- | lib/libppmd.c | 228 |
1 files changed, 142 insertions, 86 deletions
diff --git a/lib/libppmd.c b/lib/libppmd.c index 2325dd68..262679ec 100644 --- a/lib/libppmd.c +++ b/lib/libppmd.c @@ -18,9 +18,9 @@ #include <assert.h> #include <stdlib.h> -#include "pm_config.h" -#include "pm_c_util.h" -#include "mallocvar.h" +#include "netpbm/pm_config.h" +#include "netpbm/pm_c_util.h" +#include "netpbm/mallocvar.h" #include "ppm.h" #include "ppmdfont.h" #include "ppmdraw.h" @@ -966,14 +966,25 @@ typedef struct int edge; } coord; -typedef struct fillobj { +typedef struct fillState { int n; + /* Number of elements in 'coords' */ int size; int curedge; int segstart; int ydir; int startydir; coord * coords; +} fillState; + +typedef struct fillobj { + + /* The only reason we have a struct fillState separate from + struct fillobj is that the drawproc interface is defined to + have drawing not modify the fillobj, i.e. it passed + const fillobj * to the drawing program. + */ + struct fillState * stateP; } fillobj; #define SOME 1000 @@ -984,16 +995,24 @@ struct fillobj * ppmd_fill_create(void) { fillobj * fillObjP; + struct fillState * stateP; MALLOCVAR(fillObjP); if (fillObjP == NULL) pm_error("out of memory allocating a fillhandle"); - fillObjP->n = 0; - fillObjP->size = SOME; - MALLOCARRAY(fillObjP->coords, fillObjP->size); - if (fillObjP->coords == NULL) + + MALLOCVAR(stateP); + if (stateP == NULL) pm_error("out of memory allocating a fillhandle"); - fillObjP->curedge = 0; + + stateP->n = 0; + stateP->size = SOME; + MALLOCARRAY(stateP->coords, stateP->size); + if (stateP->coords == NULL) + pm_error("out of memory allocating a fillhandle"); + stateP->curedge = 0; + + fillObjP->stateP = stateP; /* Turn off line clipping. */ /* UGGH! We must eliminate this global variable */ @@ -1021,14 +1040,95 @@ ppmd_fill_init(void) { void -ppmd_fill_destroy(struct fillobj * fillObjP) { +ppmd_fill_destroy(struct fillobj * const fillObjP) { - free(fillObjP->coords); + free(fillObjP->stateP->coords); + free(fillObjP->stateP); free(fillObjP); } +static void +addCoord(struct fillState * const stateP, + ppmd_point const point) { + + stateP->coords[stateP->n].point = point; + stateP->coords[stateP->n].edge = stateP->curedge; + + ++stateP->n; +} + + + +static void +startNewSegment(struct fillState * const stateP) { +/*---------------------------------------------------------------------------- + Close off the segment we're currently building and start a new one. +-----------------------------------------------------------------------------*/ + if (stateP->startydir != 0 && stateP->ydir != 0) { + /* There's stuff in the current segment. */ + if (stateP->startydir == stateP->ydir) { + /* Oops, first edge and last edge of current segment are the same. + Change all points in the first edge to be in the last. + */ + int const firstEdge = stateP->coords[stateP->segstart].edge; + int const lastEdge = stateP->coords[stateP->n - 1].edge; + coord * const segStartCoordP = &stateP->coords[stateP->segstart]; + coord * const segEndCoordP = &stateP->coords[stateP->n]; + + coord * fcP; + + for (fcP = segStartCoordP; + fcP < segEndCoordP && fcP->edge == firstEdge; + ++fcP) + fcP->edge = lastEdge; + } + } + /* And start new segment. */ + ++stateP->curedge; + stateP->segstart = stateP->n; + stateP->ydir = 0; + stateP->startydir = 0; +} + + + +static void +continueSegment(struct fillState * const stateP, + int const dy) { +/*---------------------------------------------------------------------------- + 'dy' is how much the current point is above the previous one. +-----------------------------------------------------------------------------*/ + if (dy != 0) { + if (stateP->ydir != 0 && stateP->ydir != dy) { + /* Direction changed. Insert a fake coord, old + position but new edge number. + */ + ++stateP->curedge; + addCoord(stateP, stateP->coords[stateP->n - 1].point); + } + stateP->ydir = dy; + if (stateP->startydir == 0) + stateP->startydir = dy; + } +} + + + + +/* ppmd_fill_drawprocp() is a drawproc that turns an outline drawing function + into a filled shape function. This is a somewhat off-label application of + a drawproc: A drawproc is intended just to draw a point. So e.g. you + might draw a circle with a fat brush by calling ppmd_circle with a drawproc + that draws a point as a 10-pixel disk. + + But ppmd_fill_drawproc() just draws a point the trivial way: as one pixel. + However, it tracks every point that is drawn in a form that a subsequent + ppmd_fill() call can use to to fill in the shape drawn, assuming it turns + out to be a closed shape. +*/ + void ppmd_fill_drawprocp(pixel ** const pixels, unsigned int const cols, @@ -1037,85 +1137,39 @@ ppmd_fill_drawprocp(pixel ** const pixels, ppmd_point const p, const void * const clientdata) { - fillobj * fh; - coord * cp; - - fh = (fillobj*) clientdata; + const fillobj * const fillObjP = clientdata; + struct fillState * const stateP = fillObjP->stateP; - /* If these are the same coords we saved last time, don't bother. */ - if (fh->n > 0) { - ppmd_point const lastPoint = fh->coords[fh->n - 1].point; - if (pointsEqual(p, lastPoint)) - return; - } - - /* Ok, these are new; make room for two more coords. */ - if (fh->n + 1 >= fh->size) { - fh->size += SOME; - REALLOCARRAY(fh->coords, fh->size); - if (fh->coords == NULL) + /* Make room for two more coords, the max we might add. */ + if (stateP->n + 2 > stateP->size) { + stateP->size += SOME; + REALLOCARRAY(stateP->coords, stateP->size); + if (stateP->coords == NULL) pm_error("out of memory enlarging a fillhandle"); } - /* Check for extremum and set the edge number. */ - if (fh->n == 0) { + if (stateP->n == 0) { /* Start first segment. */ - fh->segstart = fh->n; - fh->ydir = 0; - fh->startydir = 0; + stateP->segstart = stateP->n; + stateP->ydir = 0; + stateP->startydir = 0; + addCoord(stateP, p); } else { - coord * const ocp = &(fh->coords[fh->n - 1]); - int dx, dy; - - dx = p.x - ocp->point.x; - dy = p.y - ocp->point.y; - if (dx < -1 || dx > 1 || dy < -1 || dy > 1) { - /* Segment break. Close off old one. */ - if (fh->startydir != 0 && fh->ydir != 0) - if (fh->startydir == fh->ydir) { - /* Oops, first edge and last edge are the same. - Renumber the first edge in the old segment. - */ - const coord * const fcpLast= &(fh->coords[fh->n -1]); - coord * fcp; - - int oldedge; - - fcp = &(fh->coords[fh->segstart]); - oldedge = fcp->edge; - for (; fcp <= fcpLast && fcp->edge == oldedge ; ++fcp) - fcp->edge = ocp->edge; - } - /* And start new segment. */ - ++fh->curedge; - fh->segstart = fh->n; - fh->ydir = 0; - fh->startydir = 0; + ppmd_point const prevPoint = stateP->coords[stateP->n - 1].point; + int const dx = p.x - prevPoint.x; + int const dy = p.y - prevPoint.y; + + if (dx == 0 && dy == 0) { + /* These are the same coords we had last time; don't bother */ } else { - /* Segment continues. */ - if (dy != 0) { - if (fh->ydir != 0 && fh->ydir != dy) { - /* Direction changed. Insert a fake coord, old - position but new edge number. - */ - ++fh->curedge; - cp = &fh->coords[fh->n]; - cp->point = ocp->point; - cp->edge = fh->curedge; - ++fh->n; - } - fh->ydir = dy; - if (fh->startydir == 0) - fh->startydir = dy; - } + if (abs(dx) > 1 || abs(dy) > 1) + startNewSegment(stateP); + else + continueSegment(stateP, dy); + + addCoord(stateP, p); } } - - /* Save this coord. */ - cp = &fh->coords[fh->n]; - cp->point = p; - cp->edge = fh->curedge; - ++fh->n; } @@ -1137,12 +1191,12 @@ ppmd_fill_drawproc(pixel** const pixels, #ifndef LITERAL_FN_DEF_MATCH -static qsort_comparison_fn yx_compare; +static qsort_comparison_fn yxCompare; #endif static int -yx_compare(const void * const c1Arg, - const void * const c2Arg) { +yxCompare(const void * const c1Arg, + const void * const c2Arg) { const coord * const c1P = c1Arg; const coord * const c2P = c2Arg; @@ -1173,10 +1227,12 @@ ppmd_fill(pixel ** const pixels, int const cols, int const rows, pixval const maxval, - struct fillobj * const fh, + struct fillobj * const fillObjP, ppmd_drawproc drawProc, const void * const clientdata) { + struct fillState * const fh = fillObjP->stateP; + int pedge; int i, edge, lx, rx, py; coord * cp; @@ -1202,7 +1258,7 @@ ppmd_fill(pixel ** const pixels, ppmd_setlineclip(oldclip); /* Sort the coords by Y, secondarily by X. */ - qsort((char*) fh->coords, fh->n, sizeof(coord), yx_compare); + qsort((char*) fh->coords, fh->n, sizeof(coord), yxCompare); /* Find equal coords with different edge numbers, and swap if necessary. */ edge = -1; |