Fixed ClearWindow & few scroller tweaks

systematic verification of ClearWindow done ...

components/display/core/gds.c

@@ -60,14 +60,6 @@ void GDS_Clear( struct GDS_Device* Device, int Color ) {
 }
 
 void GDS_ClearWindow( struct GDS_Device* Device, int x1, int y1, int x2, int y2, int Color ) {
-	
-	for (int y = y1; y <= y2; y++) {
-			for (int x = x1; x <= x2; x++) {
-				GDS_DrawPixelFast( Device, x, y, Color);
-			}
-		}
-	return;
-	
 	// driver can provide own optimized clear window
 	if (Device->ClearWindow) {
 		Device->ClearWindow( Device, x1, y1, x2, y2, Color );
@@ -79,13 +71,21 @@ void GDS_ClearWindow( struct GDS_Device* Device, int x1, int y1, int x2, int y2,
 			uint8_t _Color = Color == GDS_COLOR_BLACK ? 0: 0xff;
 			uint8_t Width = Device->Width;
 			// try to do byte processing as much as possible
-			int c;
-			for (c = x1; c <= x2; c++) {
-				int r = y1;
-				while (r & 0x07 && r <= y2) GDS_DrawPixelFast( Device, c, r++, Color);
-				//for (; (r >> 3) < (y2 >> 3); r++) Device->Framebuffer[(r >> 3) * Width + c] = _Color;
-				memset(Device->Framebuffer + (r >> 3) * Width + c, _Color, (y2 - r) >> 3);
-				while (r <= y2) GDS_DrawPixelFast( Device, c, r++, Color);
+			for (int r = y1; r <= y2;) {
+				int c = x1;
+				// for a row that is not on a boundary, no optimization possible
+				while (r & 0x07 && r <= y2) {
+					for (c = x1; c <= x2; c++) GDS_DrawPixelFast( Device, c, r, Color);
+					r++;
+				}
+				// go fast if we have more than 8 lines to write
+				if (r + 8 < y2) {
+					memset(Device->Framebuffer + Width * r / 8 + x1, _Color, x2 - x1 + 1);
+					r += 8;
+				} else while (r <= y2) {
+					for (c = x1; c <= x2; c++) GDS_DrawPixelFast( Device, c, r, Color);
+					r++;
+				}
 			}
 		}
 	} if (Device->Depth == 4) {
@@ -96,20 +96,17 @@ void GDS_ClearWindow( struct GDS_Device* Device, int x1, int y1, int x2, int y2,
 			uint8_t _Color = Color | (Color << 4);
 			uint8_t Width = Device->Width;
 			// try to do byte processing as much as possible
-			int r;
-			for (r = y1; r <= y2; r++) {
+			for (int r = y1; r <= y2; r++) {
 				int c = x1;
 				if (c & 0x01) GDS_DrawPixelFast( Device, c++, r, Color);
-				//for (; (c >> 1) < (x2 >> 1); c++) Device->Framebuffer[(r * Width + c) >> 1] = _Color;
-				memset(Device->Framebuffer + ((r * Width +c)  >> 1), _Color, (x2 - c) >> 1);
-				if (c < x2) GDS_DrawPixelFast( Device, c, r, Color);
+				int chunk = (x2 - c + 1) >> 1;
+				memset(Device->Framebuffer + ((r * Width + c)  >> 1), _Color, chunk);
+				if (c + chunk <= x2) GDS_DrawPixelFast( Device, x2, r, Color);
 			}
-		}
+		}	
 	} else {
-		int y;
-		for (y = y1; y <= y2; y++) {
-			int x;
-			for (x = x1; x <= x2; x++) {
+		for (int y = y1; y <= y2; y++) {
+			for (int x = x1; x <= x2; x++) {
 				GDS_DrawPixelFast( Device, x, y, Color);
 			}
 		}

components/squeezelite/display.c

@@ -500,8 +500,9 @@ static void grfe_handler( u8_t *data, int len) {
 			displayer.dirty = false;
 		}	
 	
-		// draw new frame
-		GDS_DrawBitmapCBR(display, data + sizeof(struct grfe_packet), displayer.width, displayer.height, GDS_COLOR_WHITE);
+		// draw new frame, it might be less than full screen (small visu)
+		int width = ((len - sizeof(struct grfe_packet)) * 8) / displayer.height;
+		GDS_DrawBitmapCBR(display, data + sizeof(struct grfe_packet), width, displayer.height, GDS_COLOR_WHITE);
 		GDS_Update(display);
 	}	
 	
@@ -561,7 +562,7 @@ static void grfs_handler(u8_t *data, int len) {
 		
 		// background excludes space taken by visu (if any)
 		scroller.back.width = displayer.width - ((visu.mode && visu.row < SB_HEIGHT) ? visu.width : 0);
-
+		
 		// set scroller steps & beginning
 		if (pkt->direction == 1) {
 			scroller.scrolled = 0;
@@ -779,6 +780,9 @@ static void visu_handler( u8_t *data, int len) {
 			visu.border =  htonl(pkt->border);
 			bars = htonl(pkt->bars);
 			visu.spectrum_scale = htonl(pkt->spectrum_scale) / 100.;
+			
+			// might have a race condition with scroller message, so update width in case
+			if (scroller.active) scroller.back.width = displayer.width - visu.width;
 		} else {
 			// full screen visu, try to use bottom screen if available
 			visu.width = displayer.width;