I have created this sort of heatmap, but I need it to look smoother than like this 
code:
    ggplot(data = DF_with0, aes(V1, V2, fill = V3)) +                                                                           
     geom_tile() +
     xlab("X Coordinate (feet)") + ylab("Y Coordinate (feet)") +
     scale_fill_gradient(limits = c(0, 100), low = "black", high = "red") +
     scale_x_continuous(expand = c(0,0)) +
     scale_y_continuous(expand = c(0,0))
ideally I want it to look like this: 
Is there any fast way or library that I should know? Maybe I am missing something (I am quite noob).
My data frame looks like that:
 Where the V1 and the x-axis, V2 the y-axis and V3 are the values for the color filling.
Where the V1 and the x-axis, V2 the y-axis and V3 are the values for the color filling.
Thanks in advance to everyone!
 
     
    