The Quake sources as originally release under the GPL license on December 21, 1999

WinQuake/d_scana.s

@@ -0,0 +1,89 @@
+/*
+Copyright (C) 1996-1997 Id Software, Inc.
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  
+
+See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+
+*/
+//
+// d_scana.s
+// x86 assembly-language turbulent texture mapping code
+//
+
+#include "asm_i386.h"
+#include "quakeasm.h"
+#include "asm_draw.h"
+#include "d_ifacea.h"
+
+#if id386
+
+	.data
+
+	.text
+
+//----------------------------------------------------------------------
+// turbulent texture mapping code
+//----------------------------------------------------------------------
+
+	.align 4
+.globl C(D_DrawTurbulent8Span)
+C(D_DrawTurbulent8Span):
+	pushl	%ebp				// preserve caller's stack frame pointer
+	pushl	%esi				// preserve register variables
+	pushl	%edi
+	pushl	%ebx
+
+	movl	C(r_turb_s),%esi
+	movl	C(r_turb_t),%ecx
+	movl	C(r_turb_pdest),%edi
+	movl	C(r_turb_spancount),%ebx
+
+Llp:
+	movl	%ecx,%eax
+	movl	%esi,%edx
+	sarl	$16,%eax
+	movl	C(r_turb_turb),%ebp
+	sarl	$16,%edx
+	andl	$(CYCLE-1),%eax
+	andl	$(CYCLE-1),%edx
+	movl	(%ebp,%eax,4),%eax
+	movl	(%ebp,%edx,4),%edx
+	addl	%esi,%eax
+	sarl	$16,%eax
+	addl	%ecx,%edx
+	sarl	$16,%edx
+	andl	$(TURB_TEX_SIZE-1),%eax
+	andl	$(TURB_TEX_SIZE-1),%edx
+	shll	$6,%edx
+	movl	C(r_turb_pbase),%ebp
+	addl	%eax,%edx
+	incl	%edi
+	addl	C(r_turb_sstep),%esi
+	addl	C(r_turb_tstep),%ecx
+	movb	(%ebp,%edx,1),%dl
+	decl	%ebx
+	movb	%dl,-1(%edi)
+	jnz		Llp
+
+	movl	%edi,C(r_turb_pdest)
+
+	popl	%ebx				// restore register variables
+	popl	%edi
+	popl	%esi
+	popl	%ebp				// restore caller's stack frame pointer
+	ret
+
+#endif	// id386
+