I am programming system in C and I would like to draw rectangles into 2D plain with axis X and Y to represent generated data (scheduling problems).It should LOOK LIKE gant chart. Information are supplied in text file. I don't need anything fancy yet. Just something like "draw box in color Red starting at X=5, Y=3, ending at X=7,Y=5". It should support axis scaling and I would like it to generate any size of image.
Do any of you have good experience with such a tool that can be used to generate this kind of images from command-line (from some file perhaps that have each line in Color XY XY format)?
So far I see gnuplot as only feasible solution.