Implement scroll bar (not clickable yet) and sam-scrollingHEADfront

1 files changed, 95 insertions, 3 deletions

diff --git a/graphics.c b/graphics.c
index 9f14058..bbafa72 100644
--- a/graphics.c
+++ b/graphics.c
@@ -74,13 +74,105 @@ drawcontainer(GuiElement *g)
 }
 
 void
+drawtext(Rectangle rect, Rune *text, Image *fg, int firstline, int *nlinesp, int *endlinep)
+{
+	Point p = rect.min;
+	int w;
+
+	int nlines = 1;
+	int newlines = 0;
+	int endline = 0;
+	int ended = 0;
+	int xoffset = 0;
+
+	for(Rune *r = text; *r; r++){
+		switch(*r){
+		case '\n':
+			newlines++;
+Lnewline:		if(ended && endline == 0)
+				endline = nlines;
+			p.x = rect.min.x;
+			xoffset = 0;
+			if((newlines)-(*r=='\n') >= firstline)
+				p.y += font->height;
+			nlines++;
+			break;
+		case '\t':
+			w = 8-(xoffset%8);
+			xoffset += w;
+
+			w *= stringnwidth(font, " ", 1);
+			xoffset += w;
+			if(p.x+w > rect.max.x){
+				r--;
+				goto Lnewline;
+			}else
+				p.x += w;
+			break;
+		default:
+			xoffset++;
+			w = runestringnwidth(font, r, 1);
+			if(p.x+w > rect.max.x){
+				r--;
+				goto Lnewline;
+			}
+			if(!ended && (p.y+font->height) < rect.max.y){
+				if(newlines >= firstline)
+					runestringn(screen, p, fg, ZP, font, r, 1);
+			}else
+				ended = 1;
+			p.x += w;
+			break;
+		}
+	}
+
+	if(endline == 0)
+		endline = nlines;
+
+	if(nlinesp)
+		*nlinesp = nlines;
+	if(endlinep)
+		*endlinep = endline;
+}
+
+void
 drawtextbox(GuiElement *g)
 {
-	Rune *text = getprop(g, Ptext, 1).text;
+	Rune *text = getprop(g, Ptext, 0).text;
 	Image *fg = getprop(g, Ptextcolour, 1).colour->image;
-	
+	Image *scrollbg = getprop(g, Pbordercolour, 1).colour->image;
+	Image *scrollfg = getprop(g, Pbackground, 1).colour->image;
+	int firstline = getprop(g, Pscroll, 1).scroll;
+
+	int lines = 0;
+	for(Rune *r = text; *r; r++)
+		lines += (*r) == '\n';
+
+	/* draw the scroll bar background here, then draw the actual bar later */
+	Rectangle scrollbar = Rect(g->rect.min.x, g->rect.min.y, g->rect.min.x+ScrollbarWidth, g->rect.max.y);
+	Rectangle textrect = g->content;
+	textrect.min.x += ScrollbarWidth;
+
+	draw(screen, scrollbar, scrollbg, nil, ZP);
 
-	runestring(screen, g->content.min, fg, ZP, font, text);
+	int nlines, endline;
+	drawtext(textrect, text, fg, firstline, &nlines, &endline);
+
+	int height = Dy(scrollbar);
+	scrollbar.max.x -= 1;
+	scrollbar.min.y += (height * (firstline)) / nlines;
+	scrollbar.max.y -= (height * (nlines-endline)) / nlines;
+
+	if(scrollbar.min.y > (g->rect.max.y - 2))
+		scrollbar.min.y = g->rect.max.y - 2;
+
+	draw(screen, scrollbar, scrollfg, nil, ZP);
+
+	if(firstline > nlines){
+		PropVal p;
+		p.scroll = nlines - 1;
+		setprop(g, Pscroll, p, 0); /* TODO: we don't have the write lock here :) */
+	}
 }
 
 Colour *