1 files changed, 218 insertions, 0 deletions
diff --git a/src/libparsec/include/od_geomv.h b/src/libparsec/include/od_geomv.h
new file mode 100644
index 0000000..9ccac5e
--- /dev/null
+++ b/src/libparsec/include/od_geomv.h
@@ -0,0 +1,218 @@
+/*
+ * PARSEC HEADER (OBJECT)
+ * Types and Conversions for Geometry and Rasterization V1.22
+ *
+ * Copyright (c) Markus Hadwiger 1997-1999
+ * All Rights Reserved.
+ */
+
+#ifndef _OD_GEOMV_H_
+#define _OD_GEOMV_H_
+
+
+//NOTE:
+// basically, there are two important abstract types:
+// *) GEOMV_T: for geometric calculations (view-space)
+// *) RASTV_T: for rasterization calculations (screen-space)
+// rastv_t should be identical to the primitive data type
+// used by the underlying rasterization API.
+// otherwise, time-consuming conversions will take place
+// rather often.
+
+
+// fixed and floating point types
+typedef int32_t				fixed_t;
+typedef float  				psc_float_t;
+typedef double				hprec_t;
+
+
+// type for binary angle measurement
+typedef int32_t				bams_t;
+
+
+// fixed-point <-> floating-point conversions
+#define FIXED_TO_FLOAT(x)	( (psc_float_t)( (fixed_t)(x) / 65536.0 ) )
+#define FLOAT_TO_FIXED(x)	( (fixed_t)( (hprec_t)(x) * 65536.0 ) )
+
+
+// define internal conversion macros
+#define FIXED2FLOAT(x)		( (psc_float_t)( (fixed_t)(x) / 65536.0 ) )
+#define FLOAT2FIXED(x)		( (fixed_t)( (psc_float_t)(x) * 65536.0 ) )
+#define FIXED2INT(x)		( ( (fixed_t)(x) + 0x8000 ) >> 16 )
+#define INT2FIXED(x)		( (fixed_t)(x) << 16 )
+#define FLOAT2INT(x)		( (int)(psc_float_t)(x) )
+#define INT2FLOAT(x)		( (psc_float_t)(x) )
+
+
+// define coordinate conversion macros
+#ifdef SCREENVERTEX_SUBPIXEL_ACCURACY
+	#define FLOAT2COORD(x)	( (psc_float_t)( (psc_float_t)(x) * D_Value ) )
+	#define COORD2FLOAT(x)	((psc_float_t)(x))	// this doesn't account for D.
+#else
+	#define FLOAT2COORD(x)	( (long)( (psc_float_t)(x) * D_Value ) )
+	#define COORD2FLOAT(x)	INT2FLOAT(x)	// this doesn't account for D.
+#endif
+
+
+// pi and multiples
+#define HPREC_PI			((hprec_t)3.14159265359)
+#define HPREC_TWO_PI		((hprec_t)(2.0 * HPREC_PI))
+#define HPREC_HALF_PI		((hprec_t)(0.5 * HPREC_PI))
+
+// some special angle values in bams
+#define BAMS_DEG0			0x00000000
+#define BAMS_DEG45			0x00002000
+#define BAMS_DEG90			0x00004000
+#define BAMS_DEG180			0x00008000
+#define BAMS_DEG360			0x00010000
+#define BAMS_DEG720			0x00020000
+
+// conversions between angle in degrees and angle in bams
+#define DEG_TO_BAMS(x)		((bams_t)((65536.0/360.0) * (x)))
+#define BAMS_TO_DEG(x)		((hprec_t)((360.0/65536.0) * (x)))
+
+// conversions between angle in radians and angle in bams
+#define RAD_TO_BAMS(x)		((bams_t)((65536.0/HPREC_TWO_PI) * (x)))
+#define BAMS_TO_RAD(x)		((hprec_t)((HPREC_TWO_PI/65536.0) * (x)))
+
+// conversions between angle in radians and angle in degrees
+#define RAD_TO_DEG(x)		((hprec_t)((360.0/HPREC_TWO_PI) * (x)))
+#define DEG_TO_RAD(x)		((hprec_t)((HPREC_TWO_PI/360.0) * (x)))
+
+
+// access 32-bit quantity as dword
+#define DW32(x)				(*(dword*)&(x))
+
+
+// swap 32-bit quantity without intermediate temporary
+#define SWAP_VALUES_32(a,b)			{ DW32(a)^=DW32(b); DW32(b)^=DW32(a); DW32(a)^=DW32(b); }
+
+// swap two geomv_t vars (works regardless of actual geomv_t)
+#define SWAP_GEOMV(a,b)		SWAP_VALUES_32((a),(b))
+
+
+// abs() macro for 32-bit quantity (only for lvalue!)
+#define ABS32(x)		{ if ((x)<0) (x)=-(x); }
+
+
+// abs() macros for fixed_t and float_t vars (only for lvalues!)
+#define ABS_FIXED(x)		ABS32(x)
+#define ABS_FLOAT(x)		{ DW32(x)&=0x7fffffff; }
+
+
+// comparison functions with zero for geomv_t that
+// work for both fixed_t and float_t (only for lvalues!)
+
+// determine if geomv_t is zero
+#define GEOMV_ZERO(x)		(DW32(x) == 0)
+
+// determine if geomv_t is non-zero
+#define GEOMV_NONZERO(x)	(!GEOMV_ZERO(x))
+
+// determine if geomv_t is negative
+#define GEOMV_NEGATIVE(x)	( (DW32(x) & 0x80000000) != 0 )
+#define GEOMV_LTZERO(x)		GEOMV_NEGATIVE(x)
+
+// determine if geomv_t is less than or equal zero
+#define GEOMV_LEZERO(x)		(GEOMV_ZERO(x) || GEOMV_NEGATIVE(x))
+
+// determine if geomv_t is positive (in this context: non-negative)
+#define GEOMV_POSITIVE(x)	(!GEOMV_NEGATIVE(x))
+#define GEOMV_GEZERO(x)		GEOMV_POSITIVE(x)
+
+// determine if geomv_t is greater than zero
+#define GEOMV_GTZERO(x)		(GEOMV_NONZERO(x) && GEOMV_POSITIVE(x))
+
+
+
+// ---------------------------------------------------------
+// define conversion macros depending on
+// actual geomv_t and rastv_t types
+// ---------------------------------------------------------
+
+// abs() macro for geomv_t
+#define ABS_GEOMV(x)		ABS_FLOAT(x)
+
+
+// types for geometric values and rasterization values
+typedef psc_float_t			geomv_t;
+typedef psc_float_t			rastv_t;
+
+
+// special values for geometric value type
+#define GEOMV_0				((geomv_t)0.0)
+#define GEOMV_0_5			((geomv_t)0.5)
+#define GEOMV_1				((geomv_t)1.0)
+#define GEOMV_VANISHING		((geomv_t)1e-7)
+
+
+// special values for rasterization value type
+#define RASTV_0				((rastv_t)0.0)
+#define RASTV_1				((rastv_t)1.0)
+#define RASTV_VANISHING		((rastv_t)1e-7)
+
+
+// geometric value conversion macros
+#define GEOMV_TO_FIXED(x)	FLOAT2FIXED		(x)
+#define FIXED_TO_GEOMV(x)	FIXED2FLOAT		(x)
+#define GEOMV_TO_FLOAT(x)	((psc_float_t)	(x))
+#define FLOAT_TO_GEOMV(x)	((geomv_t)		(x))
+#define GEOMV_TO_COORD(x)	FLOAT2COORD		(x)
+#define COORD_TO_GEOMV(x)	COORD2FLOAT		(x)
+#define GEOMV_TO_INT(x)		FLOAT2INT		(x)
+#define INT_TO_GEOMV(x)		INT2FLOAT		(x)
+#define GEOMV_TO_RASTV(x)	((rastv_t)		(x))
+
+
+// rasterization value conversion macros
+#define RASTV_TO_FIXED(x)	FLOAT2FIXED		(x)
+#define FIXED_TO_RASTV(x)	FIXED2FLOAT		(x)
+#define RASTV_TO_FLOAT(x)	((psc_float_t)	(x))
+#define FLOAT_TO_RASTV(x)	((rastv_t)		(x))
+#define RASTV_TO_COORD(x)	FLOAT2COORD		(x)
+#define COORD_TO_RASTV(x)	COORD2FLOAT		(x)
+#define RASTV_TO_INT(x)		FLOAT2INT		(x)
+#define INT_TO_RASTV(x)		INT2FLOAT		(x)
+#define RASTV_TO_GEOMV(x)	((geomv_t)		(x))
+
+
+
+// ------------------------------------------------------
+// select type for depth values (integer or fractional)
+// ------------------------------------------------------
+
+#ifdef FRACTIONAL_DEPTH_VALUES
+
+typedef geomv_t				depth_t;
+#define DEPTH_TO_INTEGER(x)	((int32_t)GEOMV_TO_FIXED(x))
+#define DEPTH_TO_GEOMV(x)	((depth_t)(x))
+#define DEPTH_TO_RASTV(x)	GEOMV_TO_RASTV(x)
+#define DEPTH_TO_FLOAT(x)	GEOMV_TO_FLOAT(x)
+#define FIXED_TO_DEPTH(x)	FIXED_TO_GEOMV(x)
+#define FLOAT_TO_DEPTH(x)	FLOAT_TO_GEOMV(x)
+
+#else
+
+typedef int32_t				depth_t;
+#define DEPTH_TO_INTEGER(x)	((depth_t)(x))
+#define DEPTH_TO_GEOMV(x)	INT_TO_GEOMV(x)
+#define DEPTH_TO_RASTV(x)	INT_TO_RASTV(x)
+#define DEPTH_TO_FLOAT(x)	INT2FLOAT(x)
+#define FIXED_TO_DEPTH(x)	((depth_t)(x))
+#define FLOAT_TO_DEPTH(x)	FLOAT2FIXED(x)
+
+#endif
+
+//NOTE:
+// there are TWO major differences between fractional and integer
+// depth values:
+// 1. trivially, integer depth values contain no fractional
+//    part whereas fractional depth values do. (regardless of
+//    whether they are of type float_t or fixed_t.)
+// 2. the range of integer depth values is from 0 to 65535,
+//    whereas the range of fractional depth values is from 0.0 to 1.0.
+
+
+#endif // _OD_GEOMV_H_
+
+