Add gradient backgrounds

3 files changed, 122 insertions, 9 deletions

diff --git a/src/frame.h b/src/frame.h
index 791156d..e81197b 100644
--- a/src/frame.h
+++ b/src/frame.h
@@ -40,6 +40,14 @@ typedef enum
 } LengthUnits;
 
 
+typedef enum
+{
+	GRAD_NONE,
+	GRAD_HORIZ,
+	GRAD_VERT
+} GradientType;
+
+
 struct frame
 {
 	struct frame            **children;
@@ -66,6 +74,8 @@ struct frame
 
 	/* Background properties for this frame */
 	double                    bgcol[4];
+	double                    bgcol2[4];
+	GradientType              grad;
 
 	/* True if this frame should be deleted on the next mouse click */
 	int                       empty;
diff --git a/src/render.c b/src/render.c
index db41402..598a40f 100644
--- a/src/render.c
+++ b/src/render.c
@@ -253,14 +253,57 @@ static void render_lines(struct frame *fr, cairo_t *cr, ImageStore *is,
 }
 
 
-static int draw_frame(cairo_t *cr, struct frame *fr, ImageStore *is,
-                     enum is_size isz)
+static void do_background(cairo_t *cr, struct frame *fr)
 {
+	cairo_pattern_t *patt = NULL;
+
 	cairo_new_path(cr);
 	cairo_rectangle(cr, 0.0, 0.0, fr->w, fr->h);
-	cairo_set_source_rgba(cr, fr->bgcol[0], fr->bgcol[1], fr->bgcol[2],
-	                          fr->bgcol[3]);
+
+	switch ( fr->grad ) {
+
+		case GRAD_NONE:
+		cairo_set_source_rgba(cr, fr->bgcol[0],
+		                          fr->bgcol[1],
+		                          fr->bgcol[2],
+			                  fr->bgcol[3]);
+		break;
+
+		case GRAD_VERT:
+		patt = cairo_pattern_create_linear(0.0, 0.0,
+			                           0.0, fr->h);
+		cairo_pattern_add_color_stop_rgb(patt, 0.0, fr->bgcol[0],
+			                                    fr->bgcol[1],
+			                                    fr->bgcol[2]);
+		cairo_pattern_add_color_stop_rgb(patt, 1.0, fr->bgcol2[0],
+			                                    fr->bgcol2[1],
+			                                    fr->bgcol2[2]);
+		cairo_set_source(cr, patt);
+		break;
+
+		case GRAD_HORIZ:
+		patt = cairo_pattern_create_linear(0.0, 0.0,
+			                           fr->w, 0.0);
+		cairo_pattern_add_color_stop_rgb(patt, 0.0, fr->bgcol[0],
+			                                    fr->bgcol[1],
+			                                    fr->bgcol[2]);
+		cairo_pattern_add_color_stop_rgb(patt, 1.0, fr->bgcol2[0],
+			                                    fr->bgcol2[1],
+			                                    fr->bgcol2[2]);
+		cairo_set_source(cr, patt);
+		break;
+
+	}
+
 	cairo_fill(cr);
+	if ( patt != NULL ) cairo_pattern_destroy(patt);
+}
+
+
+static int draw_frame(cairo_t *cr, struct frame *fr, ImageStore *is,
+                     enum is_size isz)
+{
+	do_background(cr, fr);
 
 	if ( fr->trouble ) {
 		cairo_new_path(cr);
diff --git a/src/sc_interp.c b/src/sc_interp.c
index 525b54a..646a132 100644
--- a/src/sc_interp.c
+++ b/src/sc_interp.c
@@ -236,6 +236,48 @@ static void set_frame_bgcolour(struct frame *fr, const char *colour)
 	fr->bgcol[1] = col.green;
 	fr->bgcol[2] = col.blue;
 	fr->bgcol[3] = col.alpha;
+	fr->grad = GRAD_NONE;
+}
+
+
+static void set_frame_bggrad(struct frame *fr, const char *options,
+                             GradientType grad)
+{
+	GdkRGBA col1, col2;
+	char *n2;
+	char *optcopy = strdup(options);
+
+	if ( fr == NULL ) return;
+
+	if ( options == NULL ) {
+		fprintf(stderr, "Invalid bg gradient spec '%s'\n", options);
+		return;
+	}
+
+	n2 = strchr(optcopy, ',');
+	if ( n2 == NULL ) {
+		fprintf(stderr, "Invalid bg gradient spec '%s'\n", options);
+		return;
+	}
+
+	n2[0] = '\0';
+
+	gdk_rgba_parse(&col1, optcopy);
+	gdk_rgba_parse(&col2, &n2[1]);
+
+	fr->bgcol[0] = col1.red;
+	fr->bgcol[1] = col1.green;
+	fr->bgcol[2] = col1.blue;
+	fr->bgcol[3] = col1.alpha;
+
+	fr->bgcol2[0] = col2.red;
+	fr->bgcol2[1] = col2.green;
+	fr->bgcol2[2] = col2.blue;
+	fr->bgcol2[3] = col2.alpha;
+
+	fr->grad = grad;
+
+	free(optcopy);
 }
 
 
@@ -596,11 +638,6 @@ static int check_outputs(SCBlock *bl, SCInterpreter *scin)
 		            scin->pc, bl, contents, scin->lang, 1,
 		            scin);
 
-	} else if ( strcmp(name, "bgcol") == 0 ) {
-		maybe_recurse_before(scin, child);
-		set_frame_bgcolour(sc_interp_get_frame(scin), options);
-		maybe_recurse_after(scin, child);
-
 	} else if ( strcmp(name, "image")==0 ) {
 		double w, h;
 		char *filename;
@@ -755,6 +792,20 @@ int sc_interp_add_blocks(SCInterpreter *scin, SCBlock *bl)
 			maybe_recurse_before(scin, child);
 			maybe_recurse_after(scin, child);
 
+		} else if ( strcmp(name, "bgcol") == 0 ) {
+			maybe_recurse_before(scin, child);
+			set_frame_bgcolour(sc_interp_get_frame(scin), options);
+			maybe_recurse_after(scin, child);
+
+		} else if ( strcmp(name, "bggradh") == 0 ) {
+			set_frame_bggrad(sc_interp_get_frame(scin), options,
+			                 GRAD_HORIZ);
+
+		} else if ( strcmp(name, "bggradv") == 0 ) {
+			set_frame_bggrad(sc_interp_get_frame(scin), options,
+			                 GRAD_VERT);
+
+
 		} else {
 
 			//fprintf(stderr, "Don't know what to do with this:\n");
@@ -854,6 +905,15 @@ void sc_interp_run_stylesheet(SCInterpreter *scin, SCBlock *bl)
 
 		} else if ( strcmp(name, "bgcol") == 0 ) {
 			set_frame_bgcolour(sc_interp_get_frame(scin), options);
+
+		} else if ( strcmp(name, "bggradh") == 0 ) {
+			set_frame_bggrad(sc_interp_get_frame(scin), options,
+			                 GRAD_HORIZ);
+
+		} else if ( strcmp(name, "bggradv") == 0 ) {
+			set_frame_bggrad(sc_interp_get_frame(scin), options,
+			                 GRAD_VERT);
+
 		}
 
 		bl = sc_block_next(bl);