render text with background and foreground 'color'

blitbuffer.c

@@ -329,6 +329,7 @@ static int addblitToBuffer(lua_State *L) {
 	int yoffs = luaL_checkint(L, 6);
 	int w = luaL_checkint(L, 7);
 	int h = luaL_checkint(L, 8);
+	double p = luaL_checknumber(L, 9);
 	int x, y;
 
 	uint8_t *dstptr;
@@ -349,7 +350,7 @@ static int addblitToBuffer(lua_State *L) {
 			for(y = 0; y < h; y++) {
 				ASSERT_BLITBUFFER_BOUNDARIES(dst, dstptr);
 				ASSERT_BLITBUFFER_BOUNDARIES(src, srcptr);
-				uint8_t v = (*dstptr & 0x0F) + (*srcptr & 0x0F);
+				uint8_t v = (int)((*dstptr & 0x0F)*(1-p) + (*srcptr & 0x0F)*p);
 				*dstptr = (*dstptr & 0xF0) | (v < 0x0F ? v : 0x0F);
 				dstptr += dst->pitch;
 				srcptr += src->pitch;
@@ -358,7 +359,7 @@ static int addblitToBuffer(lua_State *L) {
 			for(y = 0; y < h; y++) {
 				ASSERT_BLITBUFFER_BOUNDARIES(dst, dstptr);
 				ASSERT_BLITBUFFER_BOUNDARIES(src, srcptr);
-				uint8_t v = (*dstptr & 0x0F) + (*srcptr >> 4);
+				uint8_t v = (int)((*dstptr & 0x0F)*(1-p) + (*srcptr >> 4)*p);
 				*dstptr = (*dstptr & 0xF0) | (v < 0x0F ? v : 0x0F);
 				dstptr += dst->pitch;
 				srcptr += src->pitch;
@@ -381,14 +382,14 @@ static int addblitToBuffer(lua_State *L) {
 			for(x = 0; x < (w / 2); x++) {
 				ASSERT_BLITBUFFER_BOUNDARIES(dst, dstptr);
 				ASSERT_BLITBUFFER_BOUNDARIES(src, srcptr);
-				uint16_t v1 = (dstptr[x] & 0xF0) + ((srcptr[x] & 0x0F) << 4);
+				uint16_t v1 = (int)((dstptr[x] & 0xF0)*(1-p) + ((srcptr[x] & 0x0F) << 4)*p);
-				uint8_t v2 = (dstptr[x] & 0x0F) + (srcptr[x+1] >> 4);
+				uint8_t v2 = (int)((dstptr[x] & 0x0F)*(1-p) + (srcptr[x+1] >> 4)*p);
 				dstptr[x] = (v1 < 0xF0 ? v1 : 0xF0) | (v2 < 0x0F ? v2 : 0x0F);
 			}
 			if(w & 1) {
 				ASSERT_BLITBUFFER_BOUNDARIES(dst, dstptr);
 				ASSERT_BLITBUFFER_BOUNDARIES(src, srcptr);
-				uint16_t v1 = (dstptr[x] & 0xF0) + ((srcptr[x] & 0x0F) << 4);
+				uint16_t v1 = (int)((dstptr[x] & 0xF0)*(1-p) + ((srcptr[x] & 0x0F) << 4)*p);
 				dstptr[x] = (dstptr[x] & 0x0F) | (v1 < 0xF0 ? v1 : 0xF0);
 			}
 			dstptr += dst->pitch;
@@ -399,14 +400,14 @@ static int addblitToBuffer(lua_State *L) {
 			for(x = 0; x < (w / 2); x++) {
 				ASSERT_BLITBUFFER_BOUNDARIES(dst, dstptr);
 				ASSERT_BLITBUFFER_BOUNDARIES(src, srcptr);
-				uint16_t v1 = (dstptr[x] & 0xF0) + (srcptr[x] & 0xF0);
+				uint16_t v1 = (int)((dstptr[x] & 0xF0)*(1-p) + (srcptr[x] & 0xF0)*p);
-				uint8_t v2 = (dstptr[x] & 0x0F) + (srcptr[x] & 0x0F);
+				uint8_t v2 = (int)((dstptr[x] & 0x0F)*(1-p) + (srcptr[x] & 0x0F)*p);
 				dstptr[x] = (v1 < 0xF0 ? v1 : 0xF0) | (v2 < 0x0F ? v2 : 0x0F);
 			}
 			if(w & 1) {
 				ASSERT_BLITBUFFER_BOUNDARIES(dst, dstptr);
 				ASSERT_BLITBUFFER_BOUNDARIES(src, srcptr);
-				uint16_t v1 = (dstptr[x] & 0xF0) + (srcptr[x] & 0xF0);
+				uint16_t v1 = (int)((dstptr[x] & 0xF0)*(1-p) + (srcptr[x] & 0xF0)*p);
 				dstptr[x] = (dstptr[x] & 0x0F) | (v1 < 0xF0 ? v1 : 0xF0);
 			}
 			dstptr += dst->pitch;

frontend/ui/rendertext.lua

@@ -4,14 +4,16 @@ require "cache"
 TODO: all these functions should probably be methods on Face objects
 ]]--
 
-function getGlyph(face, charcode)
+function getGlyph(face, charcode, bgcolor, fgcolor)
-	local hash = "glyph|"..face.hash.."|"..charcode
+	if bgcolor == nil then bgcolor = 0.0 end
+	if fgcolor == nil then fgcolor = 1.0 end
+	local hash = "glyph|"..face.hash.."|"..charcode.."|"..bgcolor.."|"..fgcolor
 	local glyph = Cache:check(hash)
 	if glyph then
 		-- cache hit
 		return glyph[1]
 	end
-	local rendered_glyph = face.ftface:renderGlyph(charcode)
+	local rendered_glyph = face.ftface:renderGlyph(charcode, bgcolor, fgcolor)
 	if not rendered_glyph then
 		DEBUG("error rendering glyph (charcode=", charcode, ") for face", face)
 		return
@@ -75,7 +77,7 @@ function sizeUtf8Text(x, width, face, text, kerning)
 	return { x = pen_x, y_top = pen_y_top, y_bottom = pen_y_bottom}
 end
 
-function renderUtf8Text(buffer, x, y, face, text, kerning)
+function renderUtf8Text(buffer, x, y, face, text, kerning, bgcolor, fgcolor)
 	if not text then
 		DEBUG("renderUtf8Text called without text");
 		return 0
@@ -89,7 +91,7 @@ function renderUtf8Text(buffer, x, y, face, text, kerning)
 	for uchar in string.gfind(text, "([%z\1-\127\194-\244][\128-\191]*)") do
 		if pen_x < buffer_width then
 			local charcode = util.utf8charcode(uchar)
-			local glyph = getGlyph(face, charcode)
+			local glyph = getGlyph(face, charcode, bgcolor, fgcolor)
 			if kerning and (prevcharcode ~= 0) then
 				pen_x = pen_x + face.ftface:getKerning(prevcharcode, charcode)
 			end
@@ -97,7 +99,7 @@ function renderUtf8Text(buffer, x, y, face, text, kerning)
 				glyph.bb,
 				x + pen_x + glyph.l, y - glyph.t,
 				0, 0,
-				glyph.bb:getWidth(), glyph.bb:getHeight())
+				glyph.bb:getWidth(), glyph.bb:getHeight(), 1)
 			pen_x = pen_x + glyph.ax
 			prevcharcode = charcode
 		end -- if pen_x < buffer_width

ft.c

@@ -67,6 +67,8 @@ static int newFace(lua_State *L) {
 static int renderGlyph(lua_State *L) {
 	KPVFace *face = (KPVFace*) luaL_checkudata(L, 1, "ft_face");
 	int ch = luaL_checkint(L, 2);
+	double bg = luaL_checknumber(L, 3);
+	double fg = luaL_checknumber(L, 4);
 	FT_Error error = FT_Load_Char(face->face, ch, FT_LOAD_RENDER);
 	if(error) {
 		return luaL_error(L, "freetype error");
@@ -91,12 +93,13 @@ static int renderGlyph(lua_State *L) {
 	for(y = 0; y < h; y++) {
 		uint8_t *src = face->face->glyph->bitmap.buffer + y * face->face->glyph->bitmap.pitch;
 		for(x = 0; x < (w/2); x++) {
-			*dst = (src[0] & 0xF0) | (src[1] >> 4);
+			*dst = (int)(0xFF * bg - src[0] * (bg - fg)) & 0xF0 |
+				   (int)(0xFF * bg - src[1] * (bg - fg)) >> 4;
 			src+=2;
 			dst++;
 		}
 		if(w & 1) {
-			*dst = *src & 0xF0;
+			*dst = (int)(0xFF * bg - *src * (bg - fg)) & 0xF0;
 			dst++;
 		}
 	}