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diff --git a/externals/gridflow/base/flow_objects_for_image.c b/externals/gridflow/base/flow_objects_for_image.c
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+/*
+ $Id: flow_objects_for_image.c,v 1.1 2005-10-04 02:02:13 matju Exp $
+
+ GridFlow
+ Copyright (c) 2001,2002,2003 by Mathieu Bouchard
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License
+ as published by the Free Software Foundation; either version 2
+ of the License, or (at your option) any later version.
+
+ See file ../COPYING for further informations on licensing terms.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+*/
+
+#include <math.h>
+#include "grid.h.fcs"
+
+static void expect_picture (P<Dim> d) {
+ if (d->n!=3) RAISE("(height,width,chans) dimensions please");}
+static void expect_rgb_picture (P<Dim> d) {
+ expect_picture(d);
+ if (d->get(2)!=3) RAISE("(red,green,blue) channels please");}
+static void expect_rgba_picture (P<Dim> d) {
+ expect_picture(d);
+ if (d->get(2)!=4) RAISE("(red,green,blue,alpha) channels please");}
+static void expect_max_one_dim (P<Dim> d) {
+ if (d->n>1) { RAISE("expecting Dim[] or Dim[n], got %s",d->to_s()); }}
+
+//****************************************************************
+//{ Dim[A,B,*Cs]<T>,Dim[D,E]<T> -> Dim[A,B,*Cs]<T> }
+
+static void expect_convolution_matrix (P<Dim> d) {
+ if (d->n != 2) RAISE("only exactly two dimensions allowed for now (got %d)",
+ d->n);
+}
+
+// entry in a compiled convolution kernel
+struct PlanEntry { int y,x; bool neutral; };
+
+\class GridConvolve < GridObject
+struct GridConvolve : GridObject {
+ \attr Numop *op_para;
+ \attr Numop *op_fold;
+ \attr PtrGrid seed;
+ \attr PtrGrid b;
+ PtrGrid a;
+ int plann;
+ PlanEntry *plan; //Pt?
+ int margx,margy; // margins
+ GridConvolve () : plan(0) { b.constrain(expect_convolution_matrix); plan=0; }
+ \decl void initialize (Grid *r=0);
+ \decl void _0_op (Numop *op);
+ \decl void _0_fold (Numop *op);
+ \decl void _0_seed (Grid *seed);
+ \grin 0
+ \grin 1
+ template <class T> void copy_row (Pt<T> buf, int sx, int y, int x);
+ template <class T> void make_plan (T bogus);
+ ~GridConvolve () {if (plan) delete[] plan;}
+};
+
+template <class T> void GridConvolve::copy_row (Pt<T> buf, int sx, int y, int x) {
+ int day = a->dim->get(0), dax = a->dim->get(1), dac = a->dim->prod(2);
+ y=mod(y,day); x=mod(x,dax);
+ Pt<T> ap = (Pt<T>)*a + y*dax*dac;
+ while (sx) {
+ int sx1 = min(sx,dax-x);
+ COPY(buf,ap+x*dac,sx1*dac);
+ x=0;
+ buf += sx1*dac;
+ sx -= sx1;
+ }
+}
+
+static Numop *OP(Ruby x) {return FIX2PTR(Numop,rb_hash_aref(op_dict,x));}
+
+template <class T> void GridConvolve::make_plan (T bogus) {
+ P<Dim> da = a->dim, db = b->dim;
+ int dby = db->get(0);
+ int dbx = db->get(1);
+ if (plan) delete[] plan;
+ plan = new PlanEntry[dbx*dby];
+ int i=0;
+ for (int y=0; y<dby; y++) {
+ for (int x=0; x<dbx; x++) {
+ T rh = ((Pt<T>)*b)[y*dbx+x];
+ bool neutral = op_para->on(rh)->is_neutral(rh,at_right);
+ bool absorbent = op_para->on(rh)->is_absorbent(rh,at_right);
+ STACK_ARRAY(T,foo,1);
+ if (absorbent) {
+ foo[0] = 0;
+ op_para->map(1,foo,rh);
+ absorbent = op_fold->on(rh)->is_neutral(foo[0],at_right);
+ }
+ if (absorbent) continue;
+ plan[i].y = y;
+ plan[i].x = x;
+ plan[i].neutral = neutral;
+ i++;
+ }
+ }
+ plann = i;
+}
+
+GRID_INLET(GridConvolve,0) {
+ SAME_TYPE(in,b);
+ SAME_TYPE(in,seed);
+ P<Dim> da = in->dim, db = b->dim;
+ if (!db) RAISE("right inlet has no grid");
+ if (!seed) RAISE("seed missing");
+ if (db->n != 2) RAISE("right grid must have two dimensions");
+ if (da->n < 2) RAISE("left grid has less than two dimensions");
+ if (seed->dim->n != 0) RAISE("seed must be scalar");
+ if (da->get(0) < db->get(0)) RAISE("grid too small (y): %d < %d", da->get(0), db->get(0));
+ if (da->get(1) < db->get(1)) RAISE("grid too small (x): %d < %d", da->get(1), db->get(1));
+ margy = (db->get(0)-1)/2;
+ margx = (db->get(1)-1)/2;
+ a=new Grid(in->dim,in->nt);
+ out=new GridOutlet(this,0,da,in->nt);
+} GRID_FLOW {
+ COPY((Pt<T>)*a+in->dex, data, n);
+} GRID_FINISH {
+ Numop *op_put = OP(SYM(put));
+ make_plan((T)0);
+ int dbx = b->dim->get(1);
+ int day = a->dim->get(0);
+ int n = a->dim->prod(1);
+ int sx = a->dim->get(1)+dbx-1;
+ int n2 = sx*a->dim->prod(2);
+ STACK_ARRAY(T,buf,n);
+ STACK_ARRAY(T,buf2,n2);
+ T orh=0;
+ for (int iy=0; iy<day; iy++) {
+ op_put->map(n,buf,*(T *)*seed);
+ for (int i=0; i<plann; i++) {
+ int jy = plan[i].y;
+ int jx = plan[i].x;
+ T rh = ((Pt<T>)*b)[jy*dbx+jx];
+ if (i==0 || plan[i].y!=plan[i-1].y || orh!=rh) {
+ copy_row(buf2,sx,iy+jy-margy,-margx);
+ if (!plan[i].neutral) op_para->map(n2,buf2,rh);
+ }
+ op_fold->zip(n,buf,buf2+jx*a->dim->prod(2));
+ orh=rh;
+ }
+ out->send(n,buf);
+ }
+ a=0;
+} GRID_END
+
+GRID_INPUT(GridConvolve,1,b) {} GRID_END
+
+\def void _0_op (Numop *op ) { this->op_para=op; }
+\def void _0_fold (Numop *op ) { this->op_fold=op; }
+\def void _0_seed (Grid *seed) { this->seed=seed; }
+
+\def void initialize (Grid *r) {
+ rb_call_super(argc,argv);
+ this->op_para = op_mul;
+ this->op_fold = op_add;
+ this->seed = new Grid(new Dim(),int32_e,true);
+ this->b= r ? r : new Grid(new Dim(1,1),int32_e,true);
+}
+
+\classinfo { IEVAL(rself,"install '#convolve',2,1"); }
+\end class GridConvolve
+
+/* ---------------------------------------------------------------- */
+/* "#scale_by" does quick scaling of pictures by integer factors */
+/*{ Dim[A,B,3]<T> -> Dim[C,D,3]<T> }*/
+\class GridScaleBy < GridObject
+struct GridScaleBy : GridObject {
+ \attr PtrGrid scale; // integer scale factor
+ int scaley;
+ int scalex;
+ \decl void initialize (Grid *factor=0);
+ \grin 0
+ \grin 1
+ void prepare_scale_factor () {
+ scaley = ((Pt<int32>)*scale)[0];
+ scalex = ((Pt<int32>)*scale)[scale->dim->prod()==1 ? 0 : 1];
+ if (scaley<1) scaley=2;
+ if (scalex<1) scalex=2;
+ }
+};
+
+GRID_INLET(GridScaleBy,0) {
+ P<Dim> a = in->dim;
+ expect_picture(a);
+ out=new GridOutlet(this,0,new Dim(a->get(0)*scaley,a->get(1)*scalex,a->get(2)),in->nt);
+ in->set_factor(a->get(1)*a->get(2));
+} GRID_FLOW {
+ int rowsize = in->dim->prod(1);
+ STACK_ARRAY(T,buf,rowsize*scalex);
+ int chans = in->dim->get(2);
+ #define Z(z) buf[p+z]=data[i+z]
+ for (; n>0; data+=rowsize, n-=rowsize) {
+ int p=0;
+ #define LOOP(z) \
+ for (int i=0; i<rowsize; i+=z) \
+ for (int k=0; k<scalex; k++, p+=3)
+ switch (chans) {
+ case 3: LOOP(3) {Z(0);Z(1);Z(2);} break;
+ case 4: LOOP(4) {Z(0);Z(1);Z(2);Z(3);} break;
+ default: LOOP(chans) {for (int c=0; c<chans; c++) Z(c);}
+ }
+ #undef LOOP
+ for (int j=0; j<scaley; j++) out->send(rowsize*scalex,buf);
+ }
+ #undef Z
+} GRID_END
+
+static void expect_scale_factor (P<Dim> dim) {
+ if (dim->prod()!=1 && dim->prod()!=2)
+ RAISE("expecting only one or two numbers");
+}
+
+GRID_INPUT(GridScaleBy,1,scale) { prepare_scale_factor(); } GRID_END
+
+\def void initialize (Grid *factor) {
+ scale.constrain(expect_scale_factor);
+ rb_call_super(argc,argv);
+ scale=new Grid(INT2NUM(2));
+ if (factor) scale=factor;
+ prepare_scale_factor();
+}
+
+\classinfo { IEVAL(rself,"install '#scale_by',2,1"); }
+\end class GridScaleBy
+
+// ----------------------------------------------------------------
+//{ Dim[A,B,3]<T> -> Dim[C,D,3]<T> }
+\class GridDownscaleBy < GridObject
+struct GridDownscaleBy : GridObject {
+ \attr PtrGrid scale;
+ \attr bool smoothly;
+ int scaley;
+ int scalex;
+ PtrGrid temp;
+ \decl void initialize (Grid *factor=0, Symbol option=Qnil);
+ \grin 0
+ \grin 1
+ void prepare_scale_factor () {
+ scaley = ((Pt<int32>)*scale)[0];
+ scalex = ((Pt<int32>)*scale)[scale->dim->prod()==1 ? 0 : 1];
+ if (scaley<1) scaley=2;
+ if (scalex<1) scalex=2;
+ }
+};
+
+GRID_INLET(GridDownscaleBy,0) {
+
+ P<Dim> a = in->dim;
+ if (a->n!=3) RAISE("(height,width,chans) please");
+ out=new GridOutlet(this,0,new Dim(a->get(0)/scaley,a->get(1)/scalex,a->get(2)),in->nt);
+ in->set_factor(a->get(1)*a->get(2));
+ // i don't remember why two rows instead of just one.
+ temp=new Grid(new Dim(2,in->dim->get(1)/scalex,in->dim->get(2)),in->nt);
+} GRID_FLOW {
+ int rowsize = in->dim->prod(1);
+ int rowsize2 = temp->dim->prod(1);
+ Pt<T> buf = (Pt<T>)*temp; //!@#$ maybe should be something else than T ?
+ int xinc = in->dim->get(2)*scalex;
+ int y = in->dex / rowsize;
+ int chans=in->dim->get(2);
+ #define Z(z) buf[p+z]+=data[i+z]
+ if (smoothly) {
+ while (n>0) {
+ if (y%scaley==0) CLEAR(buf,rowsize2);
+ #define LOOP(z) \
+ for (int i=0,p=0; p<rowsize2; p+=z) \
+ for (int j=0; j<scalex; j++,i+=z)
+ switch (chans) {
+ case 1: LOOP(1) {Z(0);} break;
+ case 2: LOOP(2) {Z(0);Z(1);} break;
+ case 3: LOOP(3) {Z(0);Z(1);Z(2);} break;
+ case 4: LOOP(4) {Z(0);Z(1);Z(2);Z(3);} break;
+ default:LOOP(chans) {for (int k=0; k<chans; k++) Z(k);} break;
+ }
+ #undef LOOP
+ y++;
+ if (y%scaley==0 && out->dim) {
+ op_div->map(rowsize2,buf,(T)(scalex*scaley));
+ out->send(rowsize2,buf);
+ CLEAR(buf,rowsize2);
+ }
+ data+=rowsize;
+ n-=rowsize;
+ }
+ #undef Z
+ } else {
+ #define Z(z) buf[p+z]=data[i+z]
+ for (; n>0 && out->dim; data+=rowsize, n-=rowsize,y++) {
+ if (y%scaley!=0) continue;
+ #define LOOP(z) for (int i=0,p=0; p<rowsize2; i+=xinc, p+=z)
+ switch(in->dim->get(2)) {
+ case 1: LOOP(1) {Z(0);} break;
+ case 2: LOOP(2) {Z(0);Z(1);} break;
+ case 3: LOOP(3) {Z(0);Z(1);Z(2);} break;
+ case 4: LOOP(4) {Z(0);Z(1);Z(2);Z(3);} break;
+ default:LOOP(chans) {for (int k=0; k<chans; k++) Z(k);}break;
+ }
+ #undef LOOP
+ out->send(rowsize2,buf);
+ }
+ }
+ #undef Z
+} GRID_END
+
+GRID_INPUT(GridDownscaleBy,1,scale) { prepare_scale_factor(); } GRID_END
+
+\def void initialize (Grid *factor, Symbol option) {
+ scale.constrain(expect_scale_factor);
+ rb_call_super(argc,argv);
+ scale=new Grid(INT2NUM(2));
+ if (factor) scale=factor;
+ prepare_scale_factor();
+ smoothly = option==SYM(smoothly);
+}
+
+\classinfo { IEVAL(rself,"install '#downscale_by',2,1"); }
+\end class GridDownscaleBy
+
+//****************************************************************
+\class GridLayer < GridObject
+struct GridLayer : GridObject {
+ PtrGrid r;
+ GridLayer() { r.constrain(expect_rgb_picture); }
+ \grin 0 int
+ \grin 1 int
+};
+
+GRID_INLET(GridLayer,0) {
+ NOTEMPTY(r);
+ SAME_TYPE(in,r);
+ P<Dim> a = in->dim;
+ expect_rgba_picture(a);
+ if (a->get(1)!=r->dim->get(1)) RAISE("same width please");
+ if (a->get(0)!=r->dim->get(0)) RAISE("same height please");
+ in->set_factor(a->prod(2));
+ out=new GridOutlet(this,0,r->dim);
+} GRID_FLOW {
+ Pt<T> rr = ((Pt<T>)*r) + in->dex*3/4;
+ STACK_ARRAY(T,foo,n*3/4);
+#define COMPUTE_ALPHA(c,a) \
+ foo[j+c] = (data[i+c]*data[i+a] + rr[j+c]*(256-data[i+a])) >> 8
+ for (int i=0,j=0; i<n; i+=4,j+=3) {
+ COMPUTE_ALPHA(0,3);
+ COMPUTE_ALPHA(1,3);
+ COMPUTE_ALPHA(2,3);
+ }
+#undef COMPUTE_ALPHA
+ out->send(n*3/4,foo);
+} GRID_END
+
+GRID_INPUT(GridLayer,1,r) {} GRID_END
+
+\classinfo { IEVAL(rself,"install '#layer',2,1"); }
+\end class GridLayer
+
+// ****************************************************************
+// pad1,pad2 only are there for 32-byte alignment
+struct Line { int32 y1,x1,y2,x2,x,m,pad1,pad2; };
+
+static void expect_polygon (P<Dim> d) {
+ if (d->n!=2 || d->get(1)!=2) RAISE("expecting Dim[n,2] polygon");
+}
+
+\class DrawPolygon < GridObject
+struct DrawPolygon : GridObject {
+ \attr Numop *op;
+ \attr PtrGrid color;
+ \attr PtrGrid polygon;
+ PtrGrid color2;
+ PtrGrid lines;
+ int lines_start;
+ int lines_stop;
+ DrawPolygon() {
+ color.constrain(expect_max_one_dim);
+ polygon.constrain(expect_polygon);
+ }
+ \decl void initialize (Numop *op, Grid *color=0, Grid *polygon=0);
+ \grin 0
+ \grin 1
+ \grin 2 int32
+ void init_lines();
+
+};
+
+void DrawPolygon::init_lines () {
+ int nl = polygon->dim->get(0);
+ lines=new Grid(new Dim(nl,8), int32_e);
+ Pt<Line> ld = Pt<Line>((Line *)(int32 *)*lines,nl);
+ Pt<int32> pd = *polygon;
+ for (int i=0,j=0; i<nl; i++) {
+ ld[i].y1 = pd[j+0];
+ ld[i].x1 = pd[j+1];
+ j=(j+2)%(2*nl);
+ ld[i].y2 = pd[j+0];
+ ld[i].x2 = pd[j+1];
+ if (ld[i].y1>ld[i].y2) memswap(Pt<int32>(ld+i)+0,Pt<int32>(ld+i)+2,2);
+ }
+}
+
+static int order_by_starting_scanline (const void *a, const void *b) {
+ return ((Line *)a)->y1 - ((Line *)b)->y1;
+}
+
+static int order_by_column (const void *a, const void *b) {
+ return ((Line *)a)->x - ((Line *)b)->x;
+}
+
+GRID_INLET(DrawPolygon,0) {
+ NOTEMPTY(color);
+ NOTEMPTY(polygon);
+ NOTEMPTY(lines);
+ SAME_TYPE(in,color);
+ if (in->dim->n!=3) RAISE("expecting 3 dimensions");
+ if (in->dim->get(2)!=color->dim->get(0))
+ RAISE("image does not have same number of channels as stored color");
+ out=new GridOutlet(this,0,in->dim,in->nt);
+ lines_start = lines_stop = 0;
+ in->set_factor(in->dim->get(1)*in->dim->get(2));
+ int nl = polygon->dim->get(0);
+ qsort((int32 *)*lines,nl,sizeof(Line),order_by_starting_scanline);
+ int cn = color->dim->prod();
+ color2=new Grid(new Dim(cn*16), color->nt);
+ for (int i=0; i<16; i++) COPY((Pt<T>)*color2+cn*i,(Pt<T>)*color,cn);
+} GRID_FLOW {
+ int nl = polygon->dim->get(0);
+ Pt<Line> ld = Pt<Line>((Line *)(int32 *)*lines,nl);
+ int f = in->factor();
+ int y = in->dex/f;
+ int cn = color->dim->prod();
+ Pt<T> cd = (Pt<T>)*color2;
+
+ while (n) {
+ while (lines_stop != nl && ld[lines_stop].y1<=y) lines_stop++;
+ for (int i=lines_start; i<lines_stop; i++) {
+ if (ld[i].y2<=y) {
+ memswap(ld+i,ld+lines_start,1);
+ lines_start++;
+ }
+ }
+ if (lines_start == lines_stop) {
+ out->send(f,data);
+ } else {
+ int32 xl = in->dim->get(1);
+ Pt<T> data2 = ARRAY_NEW(T,f);
+ COPY(data2,data,f);
+ for (int i=lines_start; i<lines_stop; i++) {
+ Line &l = ld[i];
+ l.x = l.x1 + (y-l.y1)*(l.x2-l.x1+1)/(l.y2-l.y1+1);
+ }
+ qsort(ld+lines_start,lines_stop-lines_start,
+ sizeof(Line),order_by_column);
+ for (int i=lines_start; i<lines_stop-1; i+=2) {
+ int xs = max(ld[i].x,(int32)0), xe = min(ld[i+1].x,xl);
+ if (xs>=xe) continue; /* !@#$ WHAT? */
+ while (xe-xs>=16) { op->zip(16*cn,data2+cn*xs,cd); xs+=16; }
+ op->zip((xe-xs)*cn,data2+cn*xs,cd);
+ }
+ out->give(f,data2);
+ }
+ n-=f;
+ data+=f;
+ y++;
+ }
+} GRID_END
+
+GRID_INPUT(DrawPolygon,1,color) {} GRID_END
+GRID_INPUT(DrawPolygon,2,polygon) {init_lines();} GRID_END
+
+\def void initialize (Numop *op, Grid *color, Grid *polygon) {
+ rb_call_super(argc,argv);
+ this->op = op;
+ if (color) this->color=color;
+ if (polygon) { this->polygon=polygon; init_lines(); }
+}
+
+\classinfo { IEVAL(rself,"install '#draw_polygon',3,1"); }
+\end class DrawPolygon
+
+//****************************************************************
+static void expect_position(P<Dim> d) {
+ if (d->n!=1) RAISE("position should have 1 dimension, not %d", d->n);
+ if (d->v[0]!=2) RAISE("position dim 0 should have 2 elements, not %d", d->v[0]);
+}
+
+\class DrawImage < GridObject
+struct DrawImage : GridObject {
+ \attr Numop *op;
+ \attr PtrGrid image;
+ \attr PtrGrid position;
+ \attr bool alpha;
+ \attr bool tile;
+
+ DrawImage() : alpha(false), tile(false) {
+ position.constrain(expect_position);
+ image.constrain(expect_picture);
+ }
+
+ \decl void initialize (Numop *op, Grid *image=0, Grid *position=0);
+ \decl void _0_alpha (bool v=true);
+ \decl void _0_tile (bool v=true);
+ \grin 0
+ \grin 1
+ \grin 2 int32
+ // draw row # ry of right image in row buffer buf, starting at xs
+ // overflow on both sides has to be handled automatically by this method
+ template <class T> void draw_segment(Pt<T> obuf, Pt<T> ibuf, int ry, int x0);
+};
+
+#define COMPUTE_ALPHA(c,a) obuf[j+(c)] = ibuf[j+(c)] + (rbuf[a])*(obuf[j+(c)]-ibuf[j+(c)])/256;
+#define COMPUTE_ALPHA4(b) \
+ COMPUTE_ALPHA(b+0,b+3); \
+ COMPUTE_ALPHA(b+1,b+3); \
+ COMPUTE_ALPHA(b+2,b+3); \
+ obuf[b+3] = rbuf[b+3] + (255-rbuf[b+3])*(ibuf[j+b+3])/256;
+
+template <class T> void DrawImage::draw_segment(Pt<T> obuf, Pt<T> ibuf, int ry, int x0) {
+ if (ry<0 || ry>=image->dim->get(0)) return; // outside of image
+ int sx = in[0]->dim->get(1), rsx = image->dim->get(1);
+ int sc = in[0]->dim->get(2), rsc = image->dim->get(2);
+ Pt<T> rbuf = (Pt<T>)*image + ry*rsx*rsc;
+ if (x0>sx || x0<=-rsx) return; // outside of buffer
+ int n=rsx;
+ if (x0+n>sx) n=sx-x0;
+ if (x0<0) { rbuf-=rsc*x0; n+=x0; x0=0; }
+ if (alpha && rsc==4 && sc==3) { // RGB by RGBA //!@#$ optimise
+ int j=sc*x0;
+ for (; n; n--, rbuf+=4, j+=3) {
+ op->zip(sc,obuf+j,rbuf); COMPUTE_ALPHA(0,3); COMPUTE_ALPHA(1,3); COMPUTE_ALPHA(2,3);
+ }
+ } else if (alpha && rsc==4 && sc==4) { // RGBA by RGBA
+ op->zip(n*rsc,obuf+x0*rsc,rbuf);
+ int j=sc*x0;
+ for (; n>=4; n-=4, rbuf+=16, j+=16) {
+ COMPUTE_ALPHA4(0);COMPUTE_ALPHA4(4);
+ COMPUTE_ALPHA4(8);COMPUTE_ALPHA4(12);
+ }
+ for (; n; n--, rbuf+=4, j+=4) {
+ COMPUTE_ALPHA4(0);
+ }
+ } else { // RGB by RGB, etc
+ op->zip(n*rsc,obuf+sc*x0,rbuf);
+ }
+}
+
+GRID_INLET(DrawImage,0) {
+ NOTEMPTY(image);
+ NOTEMPTY(position);
+ SAME_TYPE(in,image);
+ if (in->dim->n!=3) RAISE("expecting 3 dimensions");
+ int lchan = in->dim->get(2);
+ int rchan = image->dim->get(2);
+ if (alpha && rchan!=4) {
+ RAISE("alpha mode works only with 4 channels in right_hand");
+ }
+ if (lchan != rchan-(alpha?1:0) && lchan != rchan) {
+ RAISE("right_hand has %d channels, alpha=%d, left_hand has %d, expecting %d or %d",
+ rchan, alpha?1:0, lchan, rchan-(alpha?1:0), rchan);
+ }
+ out=new GridOutlet(this,0,in->dim,in->nt);
+ in->set_factor(in->dim->get(1)*in->dim->get(2));
+} GRID_FLOW {
+ int f = in->factor();
+ int y = in->dex/f;
+ if (position->nt != int32_e) RAISE("position has to be int32");
+ int py = ((int32*)*position)[0], rsy = image->dim->v[0], sy=in->dim->get(0);
+ int px = ((int32*)*position)[1], rsx = image->dim->v[1], sx=in->dim->get(1);
+ for (; n; y++, n-=f, data+=f) {
+ int ty = div2(y-py,rsy);
+ if (tile || ty==0) {
+ Pt<T> data2 = ARRAY_NEW(T,f);
+ COPY(data2,data,f);
+ if (tile) {
+ for (int x=px-div2(px+rsx-1,rsx)*rsx; x<sx; x+=rsx) {
+ draw_segment(data2,data,mod(y-py,rsy),x);
+ }
+ } else {
+ draw_segment(data2,data,y-py,px);
+ }
+ out->give(f,data2);
+ } else {
+ out->send(f,data);
+ }
+ }
+} GRID_END
+
+GRID_INPUT(DrawImage,1,image) {} GRID_END
+GRID_INPUT(DrawImage,2,position) {} GRID_END
+\def void _0_alpha (bool v=true) { alpha = v; gfpost("ALPHA=%d",v); }
+\def void _0_tile (bool v=true) { tile = v; }
+
+\def void initialize (Numop *op, Grid *image, Grid *position) {
+ rb_call_super(argc,argv);
+ this->op = op;
+ if (image) this->image=image;
+ if (position) this->position=position;
+ else this->position=new Grid(new Dim(2),int32_e,true);
+}
+
+\classinfo { IEVAL(rself,"install '#draw_image',3,1"); }
+\end class DrawImage
+
+void startup_flow_objects_for_image () {
+ \startall
+}