Update a boring comment.

[narabu] / rans.shader

diff --git a/rans.shader b/rans.shader
index 8e9c4226a80a0b8595f4072490f93c072cac710d..925543ef7dfa284d0fddbce411a61444438dbc9f 100644 (file)
--- a/rans.shader
+++ b/rans.shader
@@ -97,7 +97,9 @@ void encode_coeff(int signed_k, uint sign_bias, inout RansEncoder enc)
        uint k = abs(signed_k);
 
        if (k >= ESCAPE_LIMIT) {
-               // ... boring stuff here
+               // Put the coefficient as a 1/(2^12) symbol _before_
+               // the 255 coefficient, since the decoder will read the
+               // 255 coefficient first.
                RansEncPut(enc.rans, enc.rans_offset, k, 1, prob_bits);
                k = ESCAPE_LIMIT;
        }
@@ -125,7 +127,7 @@ void encode_9_7(uint streamgroup_num, uint coeff_row, layout(r16ui) restrict rea
        uint sign_bias1 = ransdist[enc1.lut_base + 255].x + ransdist[enc1.lut_base + 255].y;
        uint sign_bias2 = ransdist[enc2.lut_base + 255].x + ransdist[enc2.lut_base + 255].y;
 
-       for (uint subblock_idx = BLOCKS_PER_STREAM; subblock_idx --> 0; ) {
+       for (uint subblock_idx = 0; subblock_idx < BLOCKS_PER_STREAM; ++subblock_idx) {
                // TODO: Use SSBOs instead of a texture?
                uint x = (streamgroup_num * BLOCKS_PER_STREAM + subblock_idx) % 160;
                uint y = (streamgroup_num * BLOCKS_PER_STREAM + subblock_idx) / 160;