From 47452495c00b48a2bdcc252c3dacd62eb2929c29 Mon Sep 17 00:00:00 2001
From: Matt Borgerson <contact@mborgerson.com>
Date: Tue, 8 Jan 2019 21:08:02 -0700
Subject: [PATCH] nv2a: Fix NV097_SET_VERTEX_DATA2S scaling
Vertex attribute values provided via NV097_SET_VERTEX_DATA2S are
apparently two 16-bit signed integers, packed into 32 bits, which are
then to be directly mapped to floating point values in the range
[-32768.0, 32767.0].
Halo:CE uses this format to provide texture (u,v) coordinates for
render-to-texture techniques, including weapon scope, dynamic shadows,
and radar beacon--all of which are now working as expected with this
patch.
---
hw/xbox/nv2a/nv2a_pgraph.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)
diff --git a/hw/xbox/nv2a/nv2a_pgraph.c b/hw/xbox/nv2a/nv2a_pgraph.c
index 88e799aeab..7f6cd011eb 100644
--- a/hw/xbox/nv2a/nv2a_pgraph.c
+++ b/hw/xbox/nv2a/nv2a_pgraph.c
@@ -2169,15 +2169,10 @@ static void pgraph_method(NV2AState *d,
case NV097_SET_VERTEX_DATA2S ...
NV097_SET_VERTEX_DATA2S + 0x3c: {
slot = (method - NV097_SET_VERTEX_DATA2S) / 4;
- assert(false); /* FIXME: Untested! */
VertexAttribute *attribute = &pg->vertex_attributes[slot];
pgraph_allocate_inline_buffer_vertices(pg, slot);
- /* FIXME: Is mapping to [-1,+1] correct? */
- attribute->inline_value[0] = ((int16_t)(parameter & 0xFFFF) * 2.0 + 1)
- / 65535.0;
- attribute->inline_value[1] = ((int16_t)(parameter >> 16) * 2.0 + 1)
- / 65535.0;
- /* FIXME: Should these really be set to 0.0 and 1.0 ? Conditions? */
+ attribute->inline_value[0] = (float)(int16_t)(parameter & 0xFFFF);
+ attribute->inline_value[1] = (float)(int16_t)(parameter >> 16);
attribute->inline_value[2] = 0.0;
attribute->inline_value[3] = 1.0;
if (slot == 0) {