Export a bunch of matrix operations from render.

The render extension uses many matrix operations internally, this change
exposes those functions to other parts of the server, drivers and
extensions. The change is motivated by the 'transform' additions to the
RandR extension but will likely be useful elsewhere.

4 files changed, 415 insertions, 72 deletions

diff --git a/render/Makefile.am b/render/Makefile.am
index e53c7c746..216c6134e 100644
--- a/render/Makefile.am
+++ b/render/Makefile.am
@@ -6,6 +6,7 @@ librender_la_SOURCES =	\
 	animcur.c	\
 	filter.c	\
 	glyph.c		\
+	matrix.c	\
 	miindex.c	\
 	mipict.c	\
 	mirect.c	\
diff --git a/render/matrix.c b/render/matrix.c
new file mode 100644
index 000000000..bd584cbd6
--- /dev/null
+++ b/render/matrix.c
@@ -0,0 +1,351 @@
+/*
+ * Copyright © 2007 Keith Packard
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission.  The copyright holders make no representations
+ * about the suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+
+#ifdef HAVE_DIX_CONFIG_H
+#include <dix-config.h>
+#endif
+
+#include "misc.h"
+#include "scrnintstr.h"
+#include "os.h"
+#include "regionstr.h"
+#include "validate.h"
+#include "windowstr.h"
+#include "input.h"
+#include "resource.h"
+#include "colormapst.h"
+#include "cursorstr.h"
+#include "dixstruct.h"
+#include "gcstruct.h"
+#include "servermd.h"
+#include "picturestr.h"
+
+#define F(x)	IntToxFixed(x)
+
+_X_EXPORT void
+PictureTransformInitIdentity (PictTransformPtr matrix)
+{
+    int	i;
+    memset (matrix, '\0', sizeof (PictTransform));
+    for (i = 0; i < 3; i++)
+	matrix->matrix[i][i] = F(1);
+}
+
+_X_EXPORT Bool
+PictureTransformPoint3d (PictTransformPtr transform,
+                         PictVectorPtr	vector)
+{
+    PictVector	    result;
+    int		    i, j;
+    xFixed_32_32    partial;
+    xFixed_48_16    v;
+
+    for (j = 0; j < 3; j++)
+    {
+	v = 0;
+	for (i = 0; i < 3; i++)
+	{
+	    partial = ((xFixed_48_16) transform->matrix[j][i] *
+		       (xFixed_48_16) vector->vector[i]);
+	    v += partial >> 16;
+	}
+	if (v > MAX_FIXED_48_16 || v < MIN_FIXED_48_16)
+	    return FALSE;
+	result.vector[j] = (xFixed) v;
+    }
+    if (!result.vector[2])
+	return FALSE;
+    *vector = result;
+    return TRUE;
+}
+
+
+_X_EXPORT Bool
+PictureTransformPoint (PictTransformPtr transform,
+		       PictVectorPtr	vector)
+{
+    PictVector	    result;
+    int		    i, j;
+    xFixed_32_32    partial;
+    xFixed_48_16    v;
+
+    for (j = 0; j < 3; j++)
+    {
+	v = 0;
+	for (i = 0; i < 3; i++)
+	{
+	    partial = ((xFixed_48_16) transform->matrix[j][i] * 
+		       (xFixed_48_16) vector->vector[i]);
+	    v += partial >> 16;
+	}
+	if (v > MAX_FIXED_48_16 || v < MIN_FIXED_48_16)
+	    return FALSE;
+	result.vector[j] = (xFixed) v;
+    }
+    if (!result.vector[2])
+	return FALSE;
+    for (j = 0; j < 2; j++)
+    {
+	partial = (xFixed_48_16) result.vector[j] << 16;
+	v = partial / result.vector[2];
+	if (v > MAX_FIXED_48_16 || v < MIN_FIXED_48_16)
+	    return FALSE;
+	vector->vector[j] = (xFixed) v;
+    }
+    vector->vector[2] = xFixed1;
+    return TRUE;
+}
+
+_X_EXPORT Bool
+PictureTransformMultiply (PictTransformPtr dst, PictTransformPtr l, PictTransformPtr r)
+{
+    PictTransform   d;
+    int		    dx, dy;
+    int		    o;
+
+    for (dy = 0; dy < 3; dy++)
+	for (dx = 0; dx < 3; dx++)
+	{
+	    xFixed_48_16    v;
+	    xFixed_32_32    partial;
+	    v = 0;
+	    for (o = 0; o < 3; o++)
+	    {
+		partial = (xFixed_32_32) l->matrix[dy][o] * (xFixed_32_32) r->matrix[o][dx];
+		v += partial >> 16;
+	    }
+	    if (v > MAX_FIXED_48_16 || v < MIN_FIXED_48_16)
+		return FALSE;
+	    d.matrix[dy][dx] = (xFixed) v;
+	}
+    *dst = d;
+    return TRUE;
+}
+
+_X_EXPORT void
+PictureTransformInitScale (PictTransformPtr t, xFixed sx, xFixed sy)
+{
+    memset (t, '\0', sizeof (PictTransform));
+    t->matrix[0][0] = sx;
+    t->matrix[1][1] = sy;
+    t->matrix[2][2] = F (1);
+}
+
+static xFixed
+fixed_inverse (xFixed x)
+{
+    return (xFixed) ((((xFixed_48_16) F(1)) * F(1)) / x);
+}
+
+_X_EXPORT Bool
+PictureTransformScale (PictTransformPtr forward,
+		       PictTransformPtr reverse,
+		       xFixed sx, xFixed sy)
+{
+    PictTransform   t;
+    
+    if (sx == 0 || sy == 0)
+	return FALSE;
+
+    PictureTransformInitScale (&t, sx, sy);
+    if (!PictureTransformMultiply (forward, &t, forward))
+	return FALSE;
+    PictureTransformInitScale (&t, fixed_inverse (sx), fixed_inverse (sy));
+    if (!PictureTransformMultiply (reverse, reverse, &t))
+	return FALSE;
+    return TRUE;
+}
+
+_X_EXPORT void
+PictureTransformInitRotate (PictTransformPtr t, xFixed c, xFixed s)
+{
+    memset (t, '\0', sizeof (PictTransform));
+    t->matrix[0][0] = c;
+    t->matrix[0][1] = -s;
+    t->matrix[1][0] = s;
+    t->matrix[1][1] = c;
+    t->matrix[2][2] = F (1);
+}
+
+_X_EXPORT Bool
+PictureTransformRotate (PictTransformPtr forward,
+			PictTransformPtr reverse,
+			xFixed c, xFixed s)
+{
+    PictTransform   t;
+    PictureTransformInitRotate (&t, c, s);
+    if (!PictureTransformMultiply (forward, &t, forward))
+	return FALSE;
+    
+    PictureTransformInitRotate (&t, c, -s);
+    if (!PictureTransformMultiply (reverse, reverse, &t))
+	return FALSE;
+    return TRUE;
+}
+
+_X_EXPORT void
+PictureTransformInitTranslate (PictTransformPtr t, xFixed tx, xFixed ty)
+{
+    memset (t, '\0', sizeof (PictTransform));
+    t->matrix[0][0] = F (1);
+    t->matrix[0][2] = tx;
+    t->matrix[1][1] = F (1);
+    t->matrix[1][2] = ty;
+    t->matrix[2][2] = F (1);
+}
+
+_X_EXPORT Bool
+PictureTransformTranslate (PictTransformPtr forward,
+			   PictTransformPtr reverse,
+			   xFixed tx, xFixed ty)
+{
+    PictTransform   t;
+    PictureTransformInitTranslate (&t, tx, ty);
+    if (!PictureTransformMultiply (forward, &t, forward))
+	return FALSE;
+    
+    PictureTransformInitTranslate (&t, -tx, -ty);
+    if (!PictureTransformMultiply (reverse, reverse, &t))
+	return FALSE;
+    return TRUE;
+}
+
+_X_EXPORT void
+PictureTransformBounds (BoxPtr b, PictTransformPtr matrix)
+{
+    PictVector	v[4];
+    int		i;
+    int		x1, y1, x2, y2;
+
+    v[0].vector[0] = F (b->x1);    v[0].vector[1] = F (b->y1);	v[0].vector[2] = F(1);
+    v[1].vector[0] = F (b->x2);    v[1].vector[1] = F (b->y1);	v[1].vector[2] = F(1);
+    v[2].vector[0] = F (b->x2);    v[2].vector[1] = F (b->y2);	v[2].vector[2] = F(1);
+    v[3].vector[0] = F (b->x1);    v[3].vector[1] = F (b->y2);	v[3].vector[2] = F(1);
+    for (i = 0; i < 4; i++)
+    {
+	PictureTransformPoint (matrix, &v[i]);
+	x1 = xFixedToInt (v[i].vector[0]);
+	y1 = xFixedToInt (v[i].vector[1]);
+	x2 = xFixedToInt (xFixedCeil (v[i].vector[0]));
+	y2 = xFixedToInt (xFixedCeil (v[i].vector[1]));
+	if (i == 0)
+	{
+	    b->x1 = x1; b->y1 = y1;
+	    b->x2 = x2; b->y2 = y2;
+	}
+	else
+	{
+	    if (x1 < b->x1) b->x1 = x1;
+	    if (y1 < b->y1) b->y1 = y1;
+	    if (x2 > b->x2) b->x2 = x2;
+	    if (y2 > b->y2) b->y2 = y2;
+	}
+    }
+}
+
+static Bool
+within_epsilon (xFixed a, xFixed b, xFixed epsilon)
+{
+    xFixed  t = a - b;
+    if (t < 0) t = -t;
+    return t <= epsilon;
+}
+
+#define epsilon	(xFixed) (2)
+
+#define IsSame(a,b) (within_epsilon (a, b, epsilon))
+#define IsZero(a)   (within_epsilon (a, 0, epsilon))
+#define IsOne(a)    (within_epsilon (a, F(1), epsilon))
+#define IsUnit(a)   (within_epsilon (a, F( 1), epsilon) || \
+		     within_epsilon (a, F(-1), epsilon) || \
+		     IsZero (a))
+#define IsInt(a)    (IsZero (xFixedFrac(a)))
+		     
+_X_EXPORT Bool
+PictureTransformIsIdentity(PictTransform *t)
+{
+    return (IsUnit (t->matrix[0][0]) &&
+	    IsUnit (t->matrix[0][1]) &&
+            IsInt  (t->matrix[0][2]) &&
+	    IsUnit (t->matrix[1][0]) &&
+	    IsUnit (t->matrix[1][1]) &&
+            IsInt  (t->matrix[1][2]) &&
+            IsZero (t->matrix[2][0]) &&
+            IsZero (t->matrix[2][1]) &&
+	    IsOne  (t->matrix[2][2]));
+}
+
+_X_EXPORT Bool
+PictureTransformIsUnit(PictTransform *t)
+{
+    return (IsSame (t->matrix[0][0],t->matrix[1][1]) &&
+	    IsSame (t->matrix[0][0], t->matrix[2][2]) &&
+            !IsZero (t->matrix[0][0]) &&
+	    IsZero (t->matrix[0][1]) &&
+            IsZero (t->matrix[0][2]) &&
+            IsZero (t->matrix[1][0]) &&
+            IsZero (t->matrix[1][2]) &&
+            IsZero (t->matrix[2][0]) &&
+            IsZero (t->matrix[2][1]));
+}
+
+_X_EXPORT Bool
+PictureTransformIsScale(PictTransform *t)
+{
+    return (!IsZero (t->matrix[0][0]) &&
+	     IsZero (t->matrix[0][1]) &&
+	     IsZero (t->matrix[0][2]) &&
+	    
+	     IsZero (t->matrix[1][0]) &&
+	    !IsZero (t->matrix[1][1]) &&
+	     IsZero (t->matrix[1][2]) &&
+	    
+	     IsZero (t->matrix[2][0]) &&
+	     IsZero (t->matrix[2][1]) &&
+	     IsOne (t->matrix[2][2]));
+}
+
+_X_EXPORT Bool
+PictureTransformIsTranslate(PictTransform *t)
+{
+    return ( IsOne  (t->matrix[0][0]) &&
+	     IsZero (t->matrix[0][1]) &&
+	     IsInt  (t->matrix[0][2]) &&
+	    
+	     IsZero (t->matrix[1][0]) &&
+	     IsOne  (t->matrix[1][1]) &&
+	     IsInt  (t->matrix[1][2]) &&
+	    
+	     IsZero (t->matrix[2][0]) &&
+	     IsZero (t->matrix[2][1]) &&
+	     IsOne  (t->matrix[2][2]));
+}
+
+_X_EXPORT Bool
+PictureTransformIsInverse (PictTransform *a, PictTransform *b)
+{
+    PictTransform   t;
+
+    PictureTransformMultiply (&t, a, b);
+    return PictureTransformIsIdentity (&t);
+}
+
diff --git a/render/picture.c b/render/picture.c
index fc2bf43d5..d672ebc8c 100644
--- a/render/picture.c
+++ b/render/picture.c
@@ -1780,67 +1780,3 @@ AddTraps (PicturePtr	pPicture,
     (*ps->AddTraps) (pPicture, xOff, yOff, ntrap, traps);
 }
 
-_X_EXPORT Bool
-PictureTransformPoint3d (PictTransformPtr transform,
-                         PictVectorPtr	vector)
-{
-    PictVector	    result;
-    int		    i, j;
-    xFixed_32_32    partial;
-    xFixed_48_16    v;
-
-    for (j = 0; j < 3; j++)
-    {
-	v = 0;
-	for (i = 0; i < 3; i++)
-	{
-	    partial = ((xFixed_48_16) transform->matrix[j][i] *
-		       (xFixed_48_16) vector->vector[i]);
-	    v += partial >> 16;
-	}
-	if (v > MAX_FIXED_48_16 || v < MIN_FIXED_48_16)
-	    return FALSE;
-	result.vector[j] = (xFixed) v;
-    }
-    if (!result.vector[2])
-	return FALSE;
-    *vector = result;
-    return TRUE;
-}
-
-
-_X_EXPORT Bool
-PictureTransformPoint (PictTransformPtr transform,
-		       PictVectorPtr	vector)
-{
-    PictVector	    result;
-    int		    i, j;
-    xFixed_32_32    partial;
-    xFixed_48_16    v;
-
-    for (j = 0; j < 3; j++)
-    {
-	v = 0;
-	for (i = 0; i < 3; i++)
-	{
-	    partial = ((xFixed_48_16) transform->matrix[j][i] * 
-		       (xFixed_48_16) vector->vector[i]);
-	    v += partial >> 16;
-	}
-	if (v > MAX_FIXED_48_16 || v < MIN_FIXED_48_16)
-	    return FALSE;
-	result.vector[j] = (xFixed) v;
-    }
-    if (!result.vector[2])
-	return FALSE;
-    for (j = 0; j < 2; j++)
-    {
-	partial = (xFixed_48_16) result.vector[j] << 16;
-	v = partial / result.vector[2];
-	if (v > MAX_FIXED_48_16 || v < MIN_FIXED_48_16)
-	    return FALSE;
-	vector->vector[j] = (xFixed) v;
-    }
-    vector->vector[2] = xFixed1;
-    return TRUE;
-}
diff --git a/render/picturestr.h b/render/picturestr.h
index 1ce16be7d..f7a066459 100644
--- a/render/picturestr.h
+++ b/render/picturestr.h
@@ -602,14 +602,6 @@ CompositeTriFan (CARD8		op,
 		 int		npoints,
 		 xPointFixed	*points);
 
-Bool
-PictureTransformPoint (PictTransformPtr transform,
-		       PictVectorPtr	vector);
-
-Bool
-PictureTransformPoint3d (PictTransformPtr transform,
-                         PictVectorPtr	vector);
-
 CARD32
 PictureGradientColor (PictGradientStopPtr stop1,
 		      PictGradientStopPtr stop2,
@@ -673,4 +665,67 @@ void PanoramiXRenderInit (void);
 void PanoramiXRenderReset (void);
 #endif
 
+/*
+ * matrix.c
+ */
+void
+PictureTransformInitIdentity (PictTransformPtr matrix);
+
+Bool
+PictureTransformPoint3d (PictTransformPtr transform,
+                         PictVectorPtr	vector);
+
+Bool
+PictureTransformPoint (PictTransformPtr transform,
+		       PictVectorPtr	vector);
+
+Bool
+PictureTransformMultiply (PictTransformPtr dst,
+			  PictTransformPtr l, PictTransformPtr r);
+
+void
+PictureTransformInitScale (PictTransformPtr t, xFixed sx, xFixed sy);
+
+Bool
+PictureTransformScale (PictTransformPtr forward,
+		       PictTransformPtr reverse,
+		       xFixed sx, xFixed sy);
+
+void
+PictureTransformInitRotate (PictTransformPtr t, xFixed c, xFixed s);
+
+Bool
+PictureTransformRotate (PictTransformPtr forward,
+			PictTransformPtr reverse,
+			xFixed c, xFixed s);
+
+void
+PictureTransformInitTranslate (PictTransformPtr t, xFixed tx, xFixed ty);
+
+Bool
+PictureTransformTranslate (PictTransformPtr forward,
+			   PictTransformPtr reverse,
+			   xFixed tx, xFixed ty);
+
+void
+PictureTransformBounds (BoxPtr b, PictTransformPtr matrix);
+
+Bool
+PictureTransformIsIdentity(PictTransform *t);
+
+Bool
+PictureTransformIsUnit(PictTransform *t);
+
+Bool
+PictureTransformIsScale(PictTransform *t);
+
+Bool
+PictureTransformIsScale(PictTransform *t);
+
+Bool
+PictureTransformIsTranslate (PictTransform *t);
+
+Bool
+PictureTransformIsInverse(PictTransform *t, PictTransform *i);
+
 #endif /* _PICTURESTR_H_ */