From 2e9df2c0991220bcd88eed8906536eb93b2138fa Mon Sep 17 00:00:00 2001
From: Ethan Lee <flibitijibibo@flibitijibibo.com>
Date: Wed, 24 Jun 2020 14:19:28 -0400
Subject: [PATCH] spirv: Fix support for POSITION1+

---
 profiles/mojoshader_profile_spirv.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/profiles/mojoshader_profile_spirv.c b/profiles/mojoshader_profile_spirv.c
index 11e04ba5..cd6489f5 100644
--- a/profiles/mojoshader_profile_spirv.c
+++ b/profiles/mojoshader_profile_spirv.c
@@ -1516,8 +1516,13 @@ static void spv_link_vs_attributes(Context *ctx, uint32 id, MOJOSHADER_usage usa
     switch (usage)
     {
         case MOJOSHADER_USAGE_POSITION:
-            assert(index == 0);
-            spv_output_builtin(ctx, id, SpvBuiltInPosition);
+            if (index == 0)
+                spv_output_builtin(ctx, id, SpvBuiltInPosition);
+            else // locations [24,32]
+            {
+                assert(index < 10);
+                spv_output_location(ctx, id, 24 + (index - 1));
+            } // else
             break;
         case MOJOSHADER_USAGE_POINTSIZE:
             spv_output_builtin(ctx, id, SpvBuiltInPointSize);
@@ -1688,6 +1693,10 @@ static void spv_link_ps_attributes(Context *ctx, uint32 id, RegisterType regtype
                 case MOJOSHADER_USAGE_NORMAL:
                     spv_output_location(ctx, id, 14 + index);
                     break;
+                case MOJOSHADER_USAGE_POSITION:
+                    assert(index > 0 && index < 10);
+                    spv_output_location(ctx, id, 24 + (index - 1));
+                    break;
                 default:
                     failf(ctx, "unexpected attribute usage %d in pixel shader", usage);
                     break;