blob: 728f3b675642300aaabb5d46ce07874dcc6dcb27 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
`include "gfx/gfx_defs.sv"
module gfx_fix_vertex
(
input logic clk,
input vec4 in_vertex,
input logic stall,
output raster_xyzw out_vertex
);
fixed x, y;
raster_xyzw fixed_vertex, corrected;
fixed[`FLOATS_PER_VEC - 1:0] fixed_vals, corrected_vals, skid_vals;
assign out_vertex = skid_vals;
assign fixed_vertex = fixed_vals;
assign corrected_vals = corrected;
assign x = fixed_vertex.xy.x;
assign y = fixed_vertex.xy.y;
genvar i;
generate
for (i = 0; i < `FLOATS_PER_VEC; ++i) begin: components
gfx_fp_fix fix
(
.in(in_vertex[i]),
.out(fixed_vals[i]),
.*
);
gfx_skid_buf #(.WIDTH($bits(fixed))) skid
(
.in(corrected_vals[i]),
.out(skid_vals[i]),
.*
);
end
endgenerate
always_ff @(posedge clk)
if (!stall) begin
/* x * `GFX_X_RES / 2
* = x * 320
* = x * 64 * 5
* = (x * 5) << 6
* = (x * (4 + 1)) << 6
* = ((x << 2) + x) << 6
*
* y * `GFX_Y_RES / 2
* = y * 240
* = y * 16 * 15
* = (y * 15) << 4
* = (y * (16 - 1)) << 4
* = ((y << 4) - y) << 4
*/
corrected.zw <= fixed_vertex.zw;
corrected.xy.x <= ((x << 2) + x) << 6;
corrected.xy.y <= ((y << 4) - y) << 4;
end
endmodule
|
