// FPGA VGA Graphics Part 1: Top Module (static squares)
// (C)2017-2018 Will Green - Licensed under the MIT License
// Heavily modified by Jens True
// Learn more at https://timetoexplore.net/blog/arty-fpga-vga-verilog-01

`default_nettype none

module vgasquare(
    input wire CLK,             // board clock: 100 MHz clock in required
    input wire RST_BTN,         // reset button
	input wire [9:0] box_x1,
	input wire [9:0] box_x2,
	input wire [8:0] box_y1,
	input wire [8:0] box_y2,    
	input wire [2:0] box_color, //1 bit for each color 
    output wire VGA_HS_O,       // horizontal sync output
    output wire VGA_VS_O,       // vertical sync output
    output wire VGA_R,    		// 1-bit VGA red output
    output wire VGA_G,    		// 1-bit VGA green output
    output wire VGA_B     		// 1-bit VGA blue output
    );

    wire rst = ~RST_BTN;    // reset is active low on AXI bus

    // generate a 25 MHz pixel strobe
    reg [15:0] cnt;
    reg pix_stb;
    always @(posedge CLK)
        {pix_stb, cnt} <= cnt + 16'h4000;  // divide by 4: (2^16)/4 = 0x4000

    wire [9:0] x;  // current pixel x position: 10-bit value: 0-1023
    wire [8:0] y;  // current pixel y position:  9-bit value: 0-511

    vga640x480 display (
        .i_clk(CLK),
        .i_pix_stb(pix_stb),
        .i_rst(rst),
        .o_hs(VGA_HS_O), 
        .o_vs(VGA_VS_O), 
        .o_x(x), 
        .o_y(y)
    );

    // Draw one square
    wire square;
    assign square = ((x > box_x1) & (y >  box_y1) & (x < box_x2) & (y < box_y1)) ? 1 : 0; //Is box within range?


    assign VGA_R = square ? box_color[0] : 0;       // Set R
    assign VGA_G = square ? box_color[1] : 0  		// Set G
    assign VGA_B = square ? box_color[2] : 0        // Set B
endmodule