GUI.vhd

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-- Company: 
-- Engineer: 
-- 
-- Create Date:    16:07:23 06/03/2025 
-- Design Name: 
-- Module Name:    GUI - Behavioral 
-- Project Name: 
-- Target Devices: 
-- Tool versions: 
-- Description: 
--
-- Dependencies: 
--
-- Revision: 
-- Revision 0.01 - File Created
-- Additional Comments: 
--
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library IEEE;
use IEEE.STD_LOGIC_1164.ALL;

-- Uncomment the following library declaration if using
-- arithmetic functions with Signed or Unsigned values
use IEEE.NUMERIC_STD.ALL;

-- Uncomment the following library declaration if instantiating
-- any Xilinx primitives in this code.
--library UNISIM;
--use UNISIM.VComponents.all;

entity GUI is port(
GPUClk : in std_logic;
x : integer range 0 to 1023;
y : integer range 0 to 1023;
color : out std_logic_vector(7 downto 0));
end GUI;

architecture Behavioral of GUI is

CONSTANT BORDER    : STD_LOGIC_VECTOR(7 DOWNTO 0) := (OTHERS => '1');
CONSTANT ACT_LSS0  : STD_LOGIC_VECTOR(7 DOWNTO 0) := "11100000";
CONSTANT ACT_EQL0  : STD_LOGIC_VECTOR(7 DOWNTO 0) := "11111100";
CONSTANT ACT_GRT0  : STD_LOGIC_VECTOR(7 DOWNTO 0) := "00011100";
CONSTANT INACTIVE  : STD_LOGIC_VECTOR(7 DOWNTO 0) := (OTHERS => '0');
CONSTANT CARTESIAN : STD_LOGIC_VECTOR(7 DOWNTO 0) := "00000011";

-- Screen Calibration
-- use this constants if you don't see plot or it's not clear
CONSTANT TOLERANCE    : INTEGER := 2;        -- Direct impact for line thickness
CONSTANT DIVIDER      : INTEGER := 1048576;  -- DIVDER of function (MUST BE POWER OF 2)
CONSTANT VERTICAL_CAL : INTEGER := 230;      -- VERTICAL function CALibration

signal fx : integer range 0 to 2147483647;

--process (x) begin
--	fx <=



begin

process (GPUClk) begin
	fx <= (((x-100)*(x-200)*(x-350)*(x-450))/DIVIDER)+VERTICAL_CAL;
	--fx <= (((x-200)*(x-200)*(x-500))/DIVIDER)+VERTICAL_CAL;
	if rising_edge(GPUClk) then
		-- Visible Area
		if ((x>=0) and (x<=639) and (y>=0) and (y<=479)) then
			if ((x=0) or (x=639) or (y=0) or (y=479)) then color <= BORDER;
			
			elsif (y=(479-VERTICAL_CAL)) then color <= CARTESIAN;
			
			elsif (abs(y-(479-fx)) <= TOLERANCE) then
				if ((fx-VERTICAL_CAL)>0) then color <= ACT_GRT0;
				elsif ((fx-VERTICAL_CAL)=0) then color <= ACT_EQL0;
				else color <= ACT_LSS0;
				end if;
			
			else color <= INACTIVE;
			end if;
		--Blanking Area
		else color <= INACTIVE;
		end if;
	end if;
end process;


end Behavioral;