diff --git a/src/gfx.c b/src/gfx.c
index 022b35e1a2..b2ba5158aa 100644
--- a/src/gfx.c
+++ b/src/gfx.c
@@ -98,8 +98,53 @@ void gfx_draw_pixel(rct_drawpixelinfo *dpi, int x, int y, int colour)
 	gfx_fill_rect(dpi, x, y, x, y, colour);
 }
 
+/*
+* Draws a horizontal line of specified colour to a buffer.
+* rct2: 0x68474C
+*/
+void gfx_draw_line_on_buffer(rct_drawpixelinfo *dpi, char colour, int y, int x, int no_pixels)
+{
+	y -= dpi->y;
+
+	//Check to make sure point is in the y range
+	if (y < 0)return;
+	if (y >= dpi->height)return;
+	//Check to make sure we are drawing at least a pixel
+	if (!no_pixels) return;
+
+	no_pixels++;
+	x -= dpi->x;
+
+	//If x coord outside range leave
+	if (x < 0){
+		//Unless the number of pixels is enough to be in range
+		no_pixels += x;
+		if (no_pixels <= 0)return;
+		//Resets starting point to 0 as we don't draw outside the range
+		x = 0;
+	}
+
+	//Ensure that the end point of the line is within range
+	if (x + no_pixels - dpi->width > 0){
+		//If the end point has any pixels outside range
+		//cut them off. If there are now no pixels return.
+		no_pixels -= x + no_pixels - dpi->width;
+		if (no_pixels <= 0)return;
+	}
+
+	char* bits_pointer;
+	//Get the buffer we are drawing to and move to the first coordinate.
+	bits_pointer = dpi->bits + y*(dpi->pitch + dpi->width) + x;
+
+	//Draw the line to the specified colour
+	for (; no_pixels > 0; --no_pixels, ++bits_pointer){
+		*((uint8*)bits_pointer) = colour;
+	}
+}
+
+
 /**
- *
+ * Draws a line on dpi if within dpi boundaries
  *  rct2: 0x00684466
  * dpi (edi)
  * x1 (ax)
@@ -110,7 +155,78 @@ void gfx_draw_pixel(rct_drawpixelinfo *dpi, int x, int y, int colour)
  */
 void gfx_draw_line(rct_drawpixelinfo *dpi, int x1, int y1, int x2, int y2, int colour)
 {
-	RCT2_CALLPROC_X(0x00684466, x1, y1, x2, y2, 0, dpi, colour);
+	// Check to make sure the line is within the drawing area
+	if ((x1 < dpi->x) && (x2 < dpi->x)){
+		return;
+	}
+
+	if ((y1 < dpi->y) && (y2 < dpi->y)){
+		return;
+	}
+
+	if ((x1 >(dpi->x + dpi->width)) && (x2 >(dpi->x + dpi->width))){
+		return;
+	}
+
+	if ((y1 > (dpi->y + dpi->height)) && (y2 > (dpi->y + dpi->height))){
+		return;
+	}
+
+	//Bresenhams algorithm
+
+	//If vertical plot points upwards
+	int steep = abs(y2 - y1) > abs(x2 - x1);
+	if (steep){
+		int temp_y2 = y2;
+		int temp_x2 = x2;
+		y2 = x1;
+		x2 = y1;
+		y1 = temp_x2;
+		x1 = temp_y2;
+	}
+
+	//If line is right to left swap direction
+	if (x1 > x2){
+		int temp_y2 = y2;
+		int temp_x2 = x2;
+		y2 = y1;
+		x2 = x1;
+		y1 = temp_y2;
+		x1 = temp_x2;
+	}
+
+	int delta_x = x2 - x1;
+	int delta_y = abs(y2 - y1);
+	int error = delta_x / 2;
+	int y_step;
+	int y = y1;
+
+	//Direction of step
+	if (y1 < y2)y_step = 1;
+	else y_step = -1;
+
+	for (int x = x1, x_start = x1, no_pixels = 1; x < x2; ++x,++no_pixels){
+		//Vertical lines are drawn 1 pixel at a time
+		if (steep)gfx_draw_line_on_buffer(dpi, colour, x, y, 1);
+
+		error -= delta_y;
+		if (error < 0){
+			//Non vertical lines are drawn with as many pixels in a horizontal line as possible
+			if (!steep)gfx_draw_line_on_buffer(dpi, colour, y, x_start, no_pixels);
+
+			//Reset non vertical line vars
+			x_start = x + 1;
+			no_pixels = 1;
+			y += y_step;
+			error += delta_x;
+		}
+
+		//Catch the case of the last line
+		if (x + 1 == x2 && !steep){
+			gfx_draw_line_on_buffer(dpi, colour, y, x_start, no_pixels);
+		}
+	}
+	return;
 }
 
 /**
diff --git a/src/window_park.c b/src/window_park.c
index e01ca4550a..6e3911f424 100644
--- a/src/window_park.c
+++ b/src/window_park.c
@@ -2139,7 +2139,6 @@ static void window_park_graph_draw_months(rct_drawpixelinfo *dpi, uint8 *history
 static void window_park_graph_draw_line_a(rct_drawpixelinfo *dpi, uint8 *history, int baseX, int baseY)
 {
 	int i, x, y, lastX, lastY;
-
 	lastX = -1;
 	x = baseX;
 	for (i = 31; i >= 0; i--) {