1 #include <u.h>
2 #include <libc.h>
3 #include <draw.h>
4 #include <event.h>
5
6 enum
7 {
8 Margin = 4, /* outside to text */
9 Border = 2, /* outside to selection boxes */
10 Blackborder = 2, /* width of outlining border */
11 Vspacing = 2, /* extra spacing between lines of text */
12 Maxunscroll = 25, /* maximum #entries before scrolling turns on */
13 Nscroll = 20, /* number entries in scrolling part */
14 Scrollwid = 14, /* width of scroll bar */
15 Gap = 4, /* between text and scroll bar */
16 };
17
18 static Image *menutxt;
19 static Image *back;
20 static Image *high;
21 static Image *bord;
22 static Image *text;
23 static Image *htext;
24
25 static
26 void
menucolors(void)27 menucolors(void)
28 {
29 /* Main tone is greenish, with negative selection */
30 back = allocimagemix(display, DPalegreen, DWhite);
31 high = allocimage(display, Rect(0,0,1,1), CMAP8, 1, DDarkgreen); /* dark green */
32 bord = allocimage(display, Rect(0,0,1,1), CMAP8, 1, DMedgreen); /* not as dark green */
33 if(back==nil || high==nil || bord==nil)
34 goto Error;
35 text = display->black;
36 htext = back;
37 return;
38
39 Error:
40 freeimage(back);
41 freeimage(high);
42 freeimage(bord);
43 back = display->white;
44 high = display->black;
45 bord = display->black;
46 text = display->black;
47 htext = display->white;
48 }
49
50 /*
51 * r is a rectangle holding the text elements.
52 * return the rectangle, including its black edge, holding element i.
53 */
54 static Rectangle
menurect(Rectangle r,int i)55 menurect(Rectangle r, int i)
56 {
57 if(i < 0)
58 return Rect(0, 0, 0, 0);
59 r.min.y += (font->height+Vspacing)*i;
60 r.max.y = r.min.y+font->height+Vspacing;
61 return insetrect(r, Border-Margin);
62 }
63
64 /*
65 * r is a rectangle holding the text elements.
66 * return the element number containing p.
67 */
68 static int
menusel(Rectangle r,Point p)69 menusel(Rectangle r, Point p)
70 {
71 r = insetrect(r, Margin);
72 if(!ptinrect(p, r))
73 return -1;
74 return (p.y-r.min.y)/(font->height+Vspacing);
75 }
76
77 static
78 void
paintitem(Menu * menu,Rectangle textr,int off,int i,int highlight,Image * save,Image * restore)79 paintitem(Menu *menu, Rectangle textr, int off, int i, int highlight, Image *save, Image *restore)
80 {
81 char *item;
82 Rectangle r;
83 Point pt;
84
85 if(i < 0)
86 return;
87 r = menurect(textr, i);
88 if(restore){
89 draw(screen, r, restore, nil, restore->r.min);
90 return;
91 }
92 if(save)
93 draw(save, save->r, screen, nil, r.min);
94 item = menu->item? menu->item[i+off] : (*menu->gen)(i+off);
95 pt.x = (textr.min.x+textr.max.x-stringwidth(font, item))/2;
96 pt.y = textr.min.y+i*(font->height+Vspacing);
97 draw(screen, r, highlight? high : back, nil, pt);
98 string(screen, pt, highlight? htext : text, pt, font, item);
99 }
100
101 /*
102 * menur is a rectangle holding all the highlightable text elements.
103 * track mouse while inside the box, return what's selected when button
104 * is raised, -1 as soon as it leaves box.
105 * invariant: nothing is highlighted on entry or exit.
106 */
107 static int
menuscan(Menu * menu,int but,Mouse * m,Rectangle textr,int off,int lasti,Image * save)108 menuscan(Menu *menu, int but, Mouse *m, Rectangle textr, int off, int lasti, Image *save)
109 {
110 int i;
111
112 paintitem(menu, textr, off, lasti, 1, save, nil);
113 flushimage(display, 1); /* in case display->locking is set */
114 *m = emouse();
115 while(m->buttons & (1<<(but-1))){
116 flushimage(display, 1); /* in case display->locking is set */
117 *m = emouse();
118 i = menusel(textr, m->xy);
119 if(i != -1 && i == lasti)
120 continue;
121 paintitem(menu, textr, off, lasti, 0, nil, save);
122 if(i == -1)
123 return i;
124 lasti = i;
125 paintitem(menu, textr, off, lasti, 1, save, nil);
126 }
127 return lasti;
128 }
129
130 static void
menupaint(Menu * menu,Rectangle textr,int off,int nitemdrawn)131 menupaint(Menu *menu, Rectangle textr, int off, int nitemdrawn)
132 {
133 int i;
134
135 draw(screen, insetrect(textr, Border-Margin), back, nil, ZP);
136 for(i = 0; i<nitemdrawn; i++)
137 paintitem(menu, textr, off, i, 0, nil, nil);
138 }
139
140 static void
menuscrollpaint(Rectangle scrollr,int off,int nitem,int nitemdrawn)141 menuscrollpaint(Rectangle scrollr, int off, int nitem, int nitemdrawn)
142 {
143 Rectangle r;
144
145 draw(screen, scrollr, back, nil, ZP);
146 r.min.x = scrollr.min.x;
147 r.max.x = scrollr.max.x;
148 r.min.y = scrollr.min.y + (Dy(scrollr)*off)/nitem;
149 r.max.y = scrollr.min.y + (Dy(scrollr)*(off+nitemdrawn))/nitem;
150 if(r.max.y < r.min.y+2)
151 r.max.y = r.min.y+2;
152 border(screen, r, 1, bord, ZP);
153 if(menutxt == 0)
154 menutxt = allocimage(display, Rect(0, 0, 1, 1), CMAP8, 1, DDarkgreen);
155 if(menutxt)
156 draw(screen, insetrect(r, 1), menutxt, nil, ZP);
157 }
158
159 int
emenuhit(int but,Mouse * m,Menu * menu)160 emenuhit(int but, Mouse *m, Menu *menu)
161 {
162 int i, nitem, nitemdrawn, maxwid, lasti, off, noff, wid, screenitem;
163 int scrolling;
164 Rectangle r, menur, sc, textr, scrollr;
165 Image *b, *save;
166 Point pt;
167 char *item;
168
169 if(back == nil)
170 menucolors();
171 sc = screen->clipr;
172 replclipr(screen, 0, screen->r);
173 maxwid = 0;
174 for(nitem = 0;
175 item = menu->item? menu->item[nitem] : (*menu->gen)(nitem);
176 nitem++){
177 i = stringwidth(font, item);
178 if(i > maxwid)
179 maxwid = i;
180 }
181 if(menu->lasthit<0 || menu->lasthit>=nitem)
182 menu->lasthit = 0;
183 screenitem = (Dy(screen->r)-10)/(font->height+Vspacing);
184 if(nitem>Maxunscroll || nitem>screenitem){
185 scrolling = 1;
186 nitemdrawn = Nscroll;
187 if(nitemdrawn > screenitem)
188 nitemdrawn = screenitem;
189 wid = maxwid + Gap + Scrollwid;
190 off = menu->lasthit - nitemdrawn/2;
191 if(off < 0)
192 off = 0;
193 if(off > nitem-nitemdrawn)
194 off = nitem-nitemdrawn;
195 lasti = menu->lasthit-off;
196 }else{
197 scrolling = 0;
198 nitemdrawn = nitem;
199 wid = maxwid;
200 off = 0;
201 lasti = menu->lasthit;
202 }
203 r = insetrect(Rect(0, 0, wid, nitemdrawn*(font->height+Vspacing)), -Margin);
204 r = rectsubpt(r, Pt(wid/2, lasti*(font->height+Vspacing)+font->height/2));
205 r = rectaddpt(r, m->xy);
206 pt = ZP;
207 if(r.max.x>screen->r.max.x)
208 pt.x = screen->r.max.x-r.max.x;
209 if(r.max.y>screen->r.max.y)
210 pt.y = screen->r.max.y-r.max.y;
211 if(r.min.x<screen->r.min.x)
212 pt.x = screen->r.min.x-r.min.x;
213 if(r.min.y<screen->r.min.y)
214 pt.y = screen->r.min.y-r.min.y;
215 menur = rectaddpt(r, pt);
216 textr.max.x = menur.max.x-Margin;
217 textr.min.x = textr.max.x-maxwid;
218 textr.min.y = menur.min.y+Margin;
219 textr.max.y = textr.min.y + nitemdrawn*(font->height+Vspacing);
220 if(scrolling){
221 scrollr = insetrect(menur, Border);
222 scrollr.max.x = scrollr.min.x+Scrollwid;
223 }else
224 scrollr = Rect(0, 0, 0, 0);
225
226 b = allocimage(display, menur, screen->chan, 0, 0);
227 if(b == 0)
228 b = screen;
229 draw(b, menur, screen, nil, menur.min);
230 draw(screen, menur, back, nil, ZP);
231 border(screen, menur, Blackborder, bord, ZP);
232 save = allocimage(display, menurect(textr, 0), screen->chan, 0, -1);
233 r = menurect(textr, lasti);
234 emoveto(divpt(addpt(r.min, r.max), 2));
235 menupaint(menu, textr, off, nitemdrawn);
236 if(scrolling)
237 menuscrollpaint(scrollr, off, nitem, nitemdrawn);
238 while(m->buttons & (1<<(but-1))){
239 lasti = menuscan(menu, but, m, textr, off, lasti, save);
240 if(lasti >= 0)
241 break;
242 while(!ptinrect(m->xy, textr) && (m->buttons & (1<<(but-1)))){
243 if(scrolling && ptinrect(m->xy, scrollr)){
244 noff = ((m->xy.y-scrollr.min.y)*nitem)/Dy(scrollr);
245 noff -= nitemdrawn/2;
246 if(noff < 0)
247 noff = 0;
248 if(noff > nitem-nitemdrawn)
249 noff = nitem-nitemdrawn;
250 if(noff != off){
251 off = noff;
252 menupaint(menu, textr, off, nitemdrawn);
253 menuscrollpaint(scrollr, off, nitem, nitemdrawn);
254 }
255 }
256 flushimage(display, 1); /* in case display->locking is set */
257 *m = emouse();
258 }
259 }
260 draw(screen, menur, b, nil, menur.min);
261 if(b != screen)
262 freeimage(b);
263 freeimage(save);
264 replclipr(screen, 0, sc);
265 if(lasti >= 0){
266 menu->lasthit = lasti+off;
267 return menu->lasthit;
268 }
269 return -1;
270 }
271