1 #include <u.h>
2 #include <libc.h>
3 #include <draw.h>
4 #include <memdraw.h>
5 #include <bio.h>
6 #include "imagefile.h"
7 
8 #define	MAXLINE	70
9 
10 /*
11  * Write data
12  */
13 static
14 char*
15 writedata(Biobuf *fd, Image *image, Memimage *memimage)
16 {
17 	char *err;
18 	uchar *data;
19 	int i, x, y, ndata, depth, col, pix, xmask, pmask;
20 	ulong chan;
21 	Rectangle r;
22 
23 	if(memimage != nil){
24 		r = memimage->r;
25 		depth = memimage->depth;
26 		chan = memimage->chan;
27 	}else{
28 		r = image->r;
29 		depth = image->depth;
30 		chan = image->chan;
31 	}
32 
33 	/*
34 	 * Read image data into memory
35 	 * potentially one extra byte on each end of each scan line
36 	 */
37 	ndata = Dy(r)*(2+Dx(r)*depth/8);
38 	data = malloc(ndata);
39 	if(data == nil)
40 		return "WritePPM: malloc failed";
41 	if(memimage != nil)
42 		ndata = unloadmemimage(memimage, r, data, ndata);
43 	else
44 		ndata = unloadimage(image, r, data, ndata);
45 	if(ndata < 0){
46 		err = malloc(ERRMAX);
47 		if(err == nil)
48 			return "WritePPM: malloc failed";
49 		snprint(err, ERRMAX, "WriteGIF: %r");
50 		free(data);
51 		return err;
52 	}
53 
54 	/* Encode and emit the data */
55 	col = 0;
56 	switch(chan){
57 	case GREY1:
58 	case GREY2:
59 	case GREY4:
60 		pmask = (1<<depth)-1;
61 		xmask = 7>>drawlog2[depth];
62 		for(y=r.min.y; y<r.max.y; y++){
63 			i = (y-r.min.y)*bytesperline(r, depth);
64 			for(x=r.min.x; x<r.max.x; x++){
65 				pix = (data[i]>>depth*((xmask-x)&xmask))&pmask;
66 				if(((x+1)&xmask) == 0)
67 					i++;
68 				col += Bprint(fd, "%d ", pix);
69 				if(col >= MAXLINE-(2+1)){
70 					Bprint(fd, "\n");
71 					col = 0;
72 				}else
73 					col += Bprint(fd, " ");
74 			}
75 		}
76 		break;
77 	case	GREY8:
78 		for(i=0; i<ndata; i++){
79 			col += Bprint(fd, "%d ", data[i]);
80 			if(col >= MAXLINE-(4+1)){
81 				Bprint(fd, "\n");
82 				col = 0;
83 			}else
84 				col += Bprint(fd, " ");
85 		}
86 		break;
87 	case RGB24:
88 		for(i=0; i<ndata; i+=3){
89 			col += Bprint(fd, "%d %d %d", data[i+2], data[i+1], data[i]);
90 			if(col >= MAXLINE-(4+4+4+1)){
91 				Bprint(fd, "\n");
92 				col = 0;
93 			}else
94 				col += Bprint(fd, " ");
95 		}
96 		break;
97 	default:
98 		return "WritePPM: can't handle channel type";
99 	}
100 
101 	return nil;
102 }
103 
104 static
105 char*
106 writeppm0(Biobuf *fd, Image *image, Memimage *memimage, Rectangle r, int chan, char *comment)
107 {
108 	char *err;
109 
110 	switch(chan){
111 	case GREY1:
112 		Bprint(fd, "P1\n");
113 		break;
114 	case GREY2:
115 	case GREY4:
116 	case	GREY8:
117 		Bprint(fd, "P2\n");
118 		break;
119 	case RGB24:
120 		Bprint(fd, "P3\n");
121 		break;
122 	default:
123 		return "WritePPM: can't handle channel type";
124 	}
125 
126 	if(comment!=nil && comment[0]!='\0'){
127 		Bprint(fd, "# %s", comment);
128 		if(comment[strlen(comment)-1] != '\n')
129 			Bprint(fd, "\n");
130 	}
131 	Bprint(fd, "%d %d\n", Dx(r), Dy(r));
132 
133 	/* maximum pixel value */
134 	switch(chan){
135 	case GREY2:
136 		Bprint(fd, "%d\n", 3);
137 		break;
138 	case GREY4:
139 		Bprint(fd, "%d\n", 15);
140 		break;
141 	case	GREY8:
142 	case RGB24:
143 		Bprint(fd, "%d\n", 255);
144 		break;
145 	}
146 
147 	err = writedata(fd, image, memimage);
148 
149 	Bprint(fd, "\n");
150 	Bflush(fd);
151 	return err;
152 }
153 
154 char*
155 writeppm(Biobuf *fd, Image *image, char *comment)
156 {
157 	return writeppm0(fd, image, nil, image->r, image->chan, comment);
158 }
159 
160 char*
161 memwriteppm(Biobuf *fd, Memimage *memimage, char *comment)
162 {
163 	return writeppm0(fd, nil, memimage, memimage->r, memimage->chan, comment);
164 }