/*
 * Hardware Sprite and Supporting Modules
 *
 * by Brendan Doms, Sean McBride, Brian Shih, and Mikell Taylor
 * 		(Olin College - Computer Architecture - Fall 2005)
 * 
 */


module hardware_sprite(Reset, R, G, B, A, clk, pclk, row, col, active, posx, posy, fliph, flipv, color);

	input active, fliph, flipv, clk, pclk;
	input [9:0] col, posx;
	input [8:0] row, posy;
	input color, Reset;
	output R, G, B, A;
	
	wire sR, sG, sB, sA;
	reg [3:0] xcoord, ycoord;
	reg [2:0] shape;
	reg [22:0] shapecounter;
	reg drawing;
	
	parameter
		WIDTH = 10'd16,
		HEIGHT = 10'd16;
	
	sprite_memory spritemem0 (Reset, sR, sG, sB, sA, clk, pclk, xcoord, ycoord, shape);
	
	and a0 (R, sR, drawing);
	and a1 (G, sG, drawing);
	and a2 (B, sB, drawing);
	and a3 (A, sA, drawing);
	
	// Initialize values
	always @(posedge clk) begin
		if (Reset) begin
			// Initialize things
			shapecounter = 0;
			if (color == 0)
				shape = 0;
			else if (color == 1)
				shape = 2;
		end
		else begin
			// Change the shape
			shapecounter = shapecounter + 1;
			if (shapecounter == 0) begin
				if (shape == 0)
					shape = 1;
				else if (shape == 1)
					shape = 0;
				else if (shape == 2)
					shape = 3;
				else if (shape == 3)
					shape = 2;
			end
		end
	end
	
	always @(posedge pclk) begin
		drawing = (active && (col >= posx) && (col < posx + WIDTH) && (row >= posy) && (row < posy + HEIGHT));
		// Make sure NEXT pixel is being requested
		xcoord = col-posx+1;
		// Current row requested
		ycoord = row-posy;
	end

endmodule

// Video selector, essentially a 3 bit mux
module video_selector(ROut, GOut, BOut, RIn, GIn, BIn, R, G, B, A);

	output ROut, GOut, BOut;
	input RIn, GIn, BIn, R, G, B, A;
	
	Mux2 mR (ROut, RIn, R, A);
	Mux2 mG (GOut, GIn, G, A);
	Mux2 mB (BOut, BIn, B, A);

endmodule

module Mux2 (OUT, A, B, S);
// OUT=A if S=0, OUT=B if S=1
	output OUT;
	input A, B, S;
	wire notS, andA, andB;

	not Inv0 (notS, S);
	and And0 (andA, A, notS);
	and And1 (andB, B, S);
	or Or1 (OUT, andA, andB);
endmodule

// 16x16 sprite memory, has 6 shapes saved
module sprite_memory(Reset, R, G, B, A, clk, pclk, xcoord, ycoord, shape);

	input [3:0] xcoord, ycoord;
	input [2:0] shape;
	input clk, pclk, Reset;
	output R, G, B, A;
	
	reg R, G, B, A;
	reg [63:0] shaperow;
	
	// Sprite Shape 1 (Red Ghost 1)
	reg [63:0] shape1mem[15:0];
	
	// Sprite Shape 2 (Red Ghost 2)
	reg [63:0] shape2mem[15:0];
	
	// Sprite Shape 3 (Cyan Ghost 1)
	reg [63:0] shape3mem[15:0];
	
	// Sprite Shape 4 (Cyan Ghost 2)
	reg [63:0] shape4mem[15:0];
	
	// Initialize
	always @(posedge clk) begin
		if (Reset) begin
			// Initialize shape 1
			shape1mem[0] = 64'b0000000000000000100110011001100110011001100110010000000000000000;
			shape1mem[1] = 64'b0000000000001001100110011001100110011001100110011001000000000000;
			shape1mem[2] = 64'b0000000010011001100110011001100110011001100110011001100100000000;
			shape1mem[3] = 64'b0000100110011001111111111001100110011001111111111001100110010000;
			shape1mem[4] = 64'b1001100110011111111111111111100110011111111111111111100110011001;
			shape1mem[5] = 64'b1001100110011111001111111111100110011111001111111111100110011001;
			shape1mem[6] = 64'b1001100110011111001111111111100110011111001111111111100110011001;
			shape1mem[7] = 64'b1001100110011001001111111001100110011001001111111001100110011001;
			shape1mem[8] = 64'b1001100110011001100110011001100110011001100110011001100110011001;
			shape1mem[9] = 64'b1001100110011001100110011001100110011001100110011001100110011001;
			shape1mem[10] = 64'b1001100110011001100110011001100110011001100110011001100110011001;
			shape1mem[11] = 64'b1001100110011001100110011001100110011001100110011001100110011001;
			shape1mem[12] = 64'b1001100110011001100110011001100110011001100110011001100110011001;
			shape1mem[13] = 64'b1001100110010000100110011001100110010000100110011001100110010000;
			shape1mem[14] = 64'b1001100100000000000010011001100100000000000010011001100100000000;
			shape1mem[15] = 64'b1001000000000000000000001001000000000000000000001001000000000000;
			// Initialize shape 2
			shape2mem[0] = 64'b0000000000000000100110011001100110011001100110010000000000000000;
			shape2mem[1] = 64'b0000000000001001100110011001100110011001100110011001000000000000;
			shape2mem[2] = 64'b0000000010011001100110011001100110011001100110011001100100000000;
			shape2mem[3] = 64'b0000100110011001111111111001100110011001111111111001100110010000;
			shape2mem[4] = 64'b1001100110011111111111111111100110011111111111111111100110011001;
			shape2mem[5] = 64'b1001100110011111001111111111100110011111001111111111100110011001;
			shape2mem[6] = 64'b1001100110011111001111111111100110011111001111111111100110011001;
			shape2mem[7] = 64'b1001100110011001001111111001100110011001001111111001100110011001;
			shape2mem[8] = 64'b1001100110011001100110011001100110011001100110011001100110011001;
			shape2mem[9] = 64'b1001100110011001100110011001100110011001100110011001100110011001;
			shape2mem[10] = 64'b1001100110011001100110011001100110011001100110011001100110011001;
			shape2mem[11] = 64'b1001100110011001100110011001100110011001100110011001100110011001;
			shape2mem[12] = 64'b1001100110011001100110011001100110011001100110011001100110011001;
			shape2mem[13] = 64'b0000100110011001100110010000100110011001100110010000100110011001;
			shape2mem[14] = 64'b0000000010011001100100000000000010011001100100000000000010011001;
			shape2mem[15] = 64'b0000000000001001000000000000000000001001000000000000000000001001;
			// Initialize shape 3
			shape3mem[0] = 64'b0000000000000000011101110111011101110111011101110000000000000000;
			shape3mem[1] = 64'b0000000000000111011101110111011101110111011101110111000000000000;
			shape3mem[2] = 64'b0000000001110111011101110111011101110111011101110111011100000000;
			shape3mem[3] = 64'b0000011101110111111111110111011101110111111111110111011101110000;
			shape3mem[4] = 64'b0111011101111111111111111111011101111111111111111111011101110111;
			shape3mem[5] = 64'b0111011101111111001111111111011101111111001111111111011101110111;
			shape3mem[6] = 64'b0111011101111111001111111111011101111111001111111111011101110111;
			shape3mem[7] = 64'b0111011101110111001111110111011101110111001111110111011101110111;
			shape3mem[8] = 64'b0111011101110111011101110111011101110111011101110111011101110111;
			shape3mem[9] = 64'b0111011101110111011101110111011101110111011101110111011101110111;
			shape3mem[10] = 64'b0111011101110111011101110111011101110111011101110111011101110111;
			shape3mem[11] = 64'b0111011101110111011101110111011101110111011101110111011101110111;
			shape3mem[12] = 64'b0111011101110111011101110111011101110111011101110111011101110111;
			shape3mem[13] = 64'b0111011101110000011101110111011101110000011101110111011101110000;
			shape3mem[14] = 64'b0111011100000000000001110111011100000000000001110111011100000000;
			shape3mem[15] = 64'b0111000000000000000000000111000000000000000000000111000000000000;
			// Initialize shape 4
			shape4mem[0] = 64'b0000000000000000011101110111011101110111011101110000000000000000;
			shape4mem[1] = 64'b0000000000000111011101110111011101110111011101110111000000000000;
			shape4mem[2] = 64'b0000000001110111011101110111011101110111011101110111011100000000;
			shape4mem[3] = 64'b0000011101110111111111110111011101110111111111110111011101110000;
			shape4mem[4] = 64'b0111011101111111111111111111011101111111111111111111011101110111;
			shape4mem[5] = 64'b0111011101111111001111111111011101111111001111111111011101110111;
			shape4mem[6] = 64'b0111011101111111001111111111011101111111001111111111011101110111;
			shape4mem[7] = 64'b0111011101110111001111110111011101110111001111110111011101110111;
			shape4mem[8] = 64'b0111011101110111011101110111011101110111011101110111011101110111;
			shape4mem[9] = 64'b0111011101110111011101110111011101110111011101110111011101110111;
			shape4mem[10] = 64'b0111011101110111011101110111011101110111011101110111011101110111;
			shape4mem[11] = 64'b0111011101110111011101110111011101110111011101110111011101110111;
			shape4mem[12] = 64'b0111011101110111011101110111011101110111011101110111011101110111;
			shape4mem[13] = 64'b0000011101110111011101110000011101110111011101110000011101110111;
			shape4mem[14] = 64'b0000000001110111011100000000000001110111011100000000000001110111;
			shape4mem[15] = 64'b0000000000000111000000000000000000000111000000000000000000000111;
		end
	end
	
	// Assign signals to proper outputs
	always @(posedge pclk) begin
		if (shape == 0)
			shaperow = shape1mem[ycoord];
		if (shape == 1)
			shaperow = shape2mem[ycoord];
		if (shape == 2)
			shaperow = shape3mem[ycoord];
		if (shape == 3)
			shaperow = shape4mem[ycoord];
		R = shaperow[(xcoord*4)+3];
		G = shaperow[(xcoord*4)+2];
		B = shaperow[(xcoord*4)+1];
		A = shaperow[xcoord*4];
	end
	
endmodule