mutter/fixed-to-float-patches/clutter-fixed.h.0.patch
Robert Bragg e8915fcb12 First cut at a fixed point to floating point conversion script + patches
This commit doesn't actually include any direct changes to source; you
have to run ./fixed-to-float.sh. Note: the script will make a number of
commits itself to your git repository a various stages of the script.
You will need to reset these if you want to re-run the script.

* NB: Be carefull about how you reset your tree, if you are making changes
to the script and patches, so you don't loose your changes *

This aims to remove all use of fixed point within Clutter and Cogl. It aims to
not break the Clutter API, including maintaining the CLUTTER_FIXED macros,
(though they now handle floats not 16.16 fixed)

It maintains cogl-fixed.[ch] as a utility API that can be used by applications
(and potentially for focused internal optimisations), but all Cogl interfaces
now accept floats in place of CoglFixed.

Note: the choice to to use single precision floats, not doubles is very
intentional. GPUs are basically all single precision; only this year have high
end cards started adding double precision - aimed mostly at the GPGPU market.
This means if you pass doubles into any GL[ES] driver, you can expect those
numbers to be cast to a float. (Certainly this is true of Mesa wich casts
most things to floats internally) It can be a noteable performance issue to
cast from double->float frequently, and if we were to have an api defined in
terms of doubles, that would imply a *lot* of unneeded casting. One of the
noteable issues with fixed point was the amount of casting required, so I
don't want to overshoot the mark and require just as much casting still. Double
precision arithmatic is also slower, so it usually makes sense to minimize its
use if the extra precision isn't needed. In the same way that the fast/low
precision fixed API can be used sparingly for optimisations; if needs be in
certain situations we can promote to doubles internally for higher precision.

E.g.
quoting Brian Paul (talking about performance optimisations for GL programmers):
"Avoid double precision valued functions
    Mesa does all internal floating point computations in single precision
    floating point. API functions which take double precision floating point
    values must convert them to single precision. This can be expensive in the
    case of glVertex, glNormal, etc. "
2008-12-22 16:59:00 +00:00

334 lines
9.2 KiB
Diff

diff --git a/clutter/clutter-fixed.h b/clutter/clutter-fixed.h
index 3ae0916..5d150da 100644
--- a/clutter/clutter-fixed.h
+++ b/clutter/clutter-fixed.h
@@ -39,126 +39,118 @@ G_BEGIN_DECLS
*
* Fixed point number (16.16)
*/
-typedef CoglFixed ClutterFixed;
+typedef float ClutterFixed;
/**
* ClutterAngle:
*
- * Integer representation of an angle such that 1024 corresponds to
- * full circle (i.e., 2*Pi).
+ * An abstract representation of an angle.
*/
-typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
+typedef float ClutterAngle;
-#define CLUTTER_ANGLE_FROM_DEG(x) (COGL_ANGLE_FROM_DEG (x))
-#define CLUTTER_ANGLE_FROM_DEGX(x) (COGL_ANGLE_FROM_DEGX (x))
-#define CLUTTER_ANGLE_TO_DEG(x) (COGL_ANGLE_TO_DEG (x))
-#define CLUTTER_ANGLE_TO_DEGX(x) (COGL_ANGLE_TO_DEGX (x))
+#define CLUTTER_ANGLE_FROM_DEG(x) ((float)(x))
+#define CLUTTER_ANGLE_FROM_DEGX(x) (CLUTTER_FIXED_TO_FLOAT (x))
+#define CLUTTER_ANGLE_TO_DEG(x) ((float)(x))
+#define CLUTTER_ANGLE_TO_DEGX(x) (CLUTTER_FLOAT_TO_FIXED (x))
/*
* some commonly used constants
*/
/**
- * CFX_Q:
- *
- * Size in bits of decimal part of floating point value.
- */
-#define CFX_Q COGL_FIXED_Q
-
-/**
* CFX_ONE:
*
* 1.0 represented as a fixed point value.
*/
-#define CFX_ONE COGL_FIXED_1
+#define CFX_ONE 1.0
/**
* CFX_HALF:
*
* 0.5 represented as a fixed point value.
*/
-#define CFX_HALF COGL_FIXED_0_5
+#define CFX_HALF 0.5
/**
* CFX_MAX:
*
* Maximum fixed point value.
*/
-#define CFX_MAX COGL_FIXED_MAX
+#define CFX_MAX G_MAXFLOAT
/**
* CFX_MIN:
*
* Minimum fixed point value.
*/
-#define CFX_MIN COGL_FIXED_MIN
+#define CFX_MIN (-G_MAXFLOAT)
/**
* CFX_PI:
*
* Fixed point representation of Pi
*/
-#define CFX_PI COGL_FIXED_PI
+#define CFX_PI G_PI
/**
* CFX_2PI:
*
* Fixed point representation of Pi*2
*/
-#define CFX_2PI COGL_FIXED_2_PI
+#define CFX_2PI (G_PI * 2)
/**
* CFX_PI_2:
*
* Fixed point representation of Pi/2
*/
-#define CFX_PI_2 COGL_FIXED_PI_2
+#define CFX_PI_2 (G_PI / 2)
/**
* CFX_PI_4:
*
* Fixed point representation of Pi/4
*/
-#define CFX_PI_4 COGL_FIXED_PI_4
+#define CFX_PI_4 (G_PI / 4)
/**
* CFX_360:
*
* Fixed point representation of the number 360
*/
-#define CFX_360 COGL_FIXED_360
+#define CFX_360 360.0
/**
* CFX_240:
*
* Fixed point representation of the number 240
*/
-#define CFX_240 COGL_FIXED_240
+#define CFX_240 240.0
/**
* CFX_180:
*
* Fixed point representation of the number 180
*/
-#define CFX_180 COGL_FIXED_180
+#define CFX_180 180.0
/**
* CFX_120:
*
* Fixed point representation of the number 120
*/
-#define CFX_120 COGL_FIXED_120
+#define CFX_120 120.0
/**
* CFX_60:
*
* Fixed point representation of the number 60
*/
-#define CFX_60 COGL_FIXED_60
+#define CFX_60 60.0
/**
* CFX_RADIANS_TO_DEGREES:
*
* Fixed point representation of the number 180 / pi
*/
-#define CFX_RADIANS_TO_DEGREES COGL_RADIANS_TO_DEGREES
+#define CFX_RADIANS_TO_DEGREES (180.0 / G_PI)
/**
* CFX_255:
*
* Fixed point representation of the number 255
*/
-#define CFX_255 COGL_FIXED_255
+#define CFX_255 255.0
/**
* CLUTTER_FIXED_TO_FLOAT:
@@ -166,7 +158,7 @@ typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
*
* Convert a fixed point value to float.
*/
-#define CLUTTER_FIXED_TO_FLOAT(x) COGL_FIXED_TO_FLOAT ((x))
+#define CLUTTER_FIXED_TO_FLOAT(x) (x)
/**
* CLUTTER_FIXED_TO_DOUBLE:
@@ -174,7 +166,7 @@ typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
*
* Convert a fixed point value to double.
*/
-#define CLUTTER_FIXED_TO_DOUBLE(x) COGL_FIXED_TO_DOUBLE ((x))
+#define CLUTTER_FIXED_TO_DOUBLE(x) ((double)(x))
/**
* CLUTTER_FLOAT_TO_FIXED:
@@ -182,7 +174,7 @@ typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
*
* Convert a float value to fixed.
*/
-#define CLUTTER_FLOAT_TO_FIXED(x) COGL_FIXED_FROM_FLOAT ((x))
+#define CLUTTER_FLOAT_TO_FIXED(x) ((x))
/**
* CLUTTER_FLOAT_TO_INT:
@@ -190,7 +182,7 @@ typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
*
* Convert a float value to int.
*/
-#define CLUTTER_FLOAT_TO_INT(x) COGL_FLOAT_TO_INT ((x))
+#define CLUTTER_FLOAT_TO_INT(x) ((int)(x))
/**
* CLUTTER_FLOAT_TO_UINT:
@@ -198,7 +190,7 @@ typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
*
* Convert a float value to unsigned int.
*/
-#define CLUTTER_FLOAT_TO_UINT(x) COGL_FLOAT_TO_UINT ((x))
+#define CLUTTER_FLOAT_TO_UINT(x) ((unsigned int)(x))
/**
* CLUTTER_INT_TO_FIXED:
@@ -206,7 +198,7 @@ typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
*
* Convert an integer value to fixed point.
*/
-#define CLUTTER_INT_TO_FIXED(x) COGL_FIXED_FROM_INT ((x))
+#define CLUTTER_INT_TO_FIXED(x) ((float)(x))
/**
* CLUTTER_FIXED_TO_INT:
@@ -216,7 +208,7 @@ typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
*
* Since: 0.6
*/
-#define CLUTTER_FIXED_TO_INT(x) COGL_FIXED_TO_INT ((x))
+#define CLUTTER_FIXED_TO_INT(x) ((int)(x))
/**
* CLUTTER_FIXED_FRACTION:
@@ -224,7 +216,7 @@ typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
*
* Retrieves the fractionary part of a fixed point value
*/
-#define CLUTTER_FIXED_FRACTION(x) COGL_FIXED_FRACTION ((x))
+#define CLUTTER_FIXED_FRACTION(x) ((x)-floorf (x))
/**
* CLUTTER_FIXED_FLOOR:
@@ -232,7 +224,7 @@ typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
*
* Round down a fixed point value to an integer.
*/
-#define CLUTTER_FIXED_FLOOR(x) COGL_FIXED_FLOOR ((x))
+#define CLUTTER_FIXED_FLOOR(x) (floorf (x))
/**
* CLUTTER_FIXED_CEIL:
@@ -240,7 +232,7 @@ typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
*
* Round up a fixed point value to an integer.
*/
-#define CLUTTER_FIXED_CEIL(x) COGL_FIXED_CEIL ((x))
+#define CLUTTER_FIXED_CEIL(x) (ceilf (x))
/**
* CLUTTER_FIXED_MUL:
@@ -249,7 +241,7 @@ typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
*
* Multiply two fixed point values
*/
-#define CLUTTER_FIXED_MUL(x,y) COGL_FIXED_MUL ((x), (y))
+#define CLUTTER_FIXED_MUL(x,y) ((x) * (y))
/**
* CLUTTER_FIXED_DIV:
@@ -258,54 +250,16 @@ typedef CoglAngle ClutterAngle; /* angle such that 1024 == 2*PI */
*
* Divide two fixed point values
*/
-#define CLUTTER_FIXED_DIV(x,y) COGL_FIXED_DIV ((x), (y))
-
-#define clutter_qmulx(x,y) cogl_fixed_mul ((x), (y))
-#define clutter_qdivx(x,y) cogl_fixed_div ((x), (y))
-
-#define clutter_sinx(a) cogl_fixed_sin ((a))
-#define clutter_sini(a) cogl_angle_sin ((a))
-#define clutter_tani(a) cogl_angle_tan ((a))
-#define clutter_atani(a) cogl_fixed_atan ((a))
-#define clutter_atan2i(x,y) cogl_fixed_atan2 ((x), (y))
-#define clutter_cosx(a) cogl_fixed_cos ((a))
-#define clutter_cosi(a) cogl_angle_cos ((a))
-
-/**
- * CLUTTER_SQRTI_ARG_MAX
- *
- * Maximum argument that can be passed to #clutter_sqrti function.
- *
- * Since: 0.6
- */
-#define CLUTTER_SQRTI_ARG_MAX COGL_SQRTI_ARG_MAX
-
-/**
- * CLUTTER_SQRTI_ARG_5_PERCENT
- *
- * Maximum argument that can be passed to #clutter_sqrti for which the
- * resulting error is < 5%
- *
- * Since: 0.6
- */
-#define CLUTTER_SQRTI_ARG_5_PERCENT COGL_SQRTI_ARG_5_PERCENT
-
-/**
- * CLUTTER_SQRTI_ARG_10_PERCENT
- *
- * Maximum argument that can be passed to #clutter_sqrti for which the
- * resulting error is < 10%
- *
- * Since: 0.6
- */
-#define CLUTTER_SQRTI_ARG_10_PERCENT COGL_SQRTI_ARG_10_PERCENT
+#define CLUTTER_FIXED_DIV(x,y) ((x) / (y))
-#define clutter_sqrtx(x) cogl_fixed_sqrt ((x))
-#define clutter_sqrti(x) cogl_sqrti ((x))
+#define clutter_qmulx(x,y) ((x) * (y))
+#define clutter_qdivx(x,y) ((x) / (y))
-#define clutter_log2x(x) cogl_fixed_log2 ((x))
-#define clutter_pow2x(x) cogl_fixed_pow2 ((x))
-#define clutter_powx(x,y) cogl_fixed_pow ((x), (y))
+#define clutter_sinx(a) sinf (a)
+#define clutter_tanx(a) tanf (a)
+#define clutter_atanx(a) atanf (a)
+#define clutter_atan2x(x,y) atan2f (x, y)
+#define clutter_cosx(a) cosf (a)
#define CLUTTER_TYPE_FIXED (clutter_fixed_get_type ())
#define CLUTTER_TYPE_PARAM_FIXED (clutter_param_fixed_get_type ())
@@ -331,7 +285,7 @@ typedef struct _ClutterParamSpecFixed ClutterParamSpecFixed;
*
* Since: 0.8
*/
-#define CLUTTER_MAXFIXED COGL_FIXED_MAX
+#define CLUTTER_MAXFIXED G_MAXFLOAT
/**
* CLUTTER_MINFIXED:
@@ -340,7 +294,7 @@ typedef struct _ClutterParamSpecFixed ClutterParamSpecFixed;
*
* Since: 0.8
*/
-#define CLUTTER_MINFIXED COGL_FIXED_MIN
+#define CLUTTER_MINFIXED (-G_MAXFLOAT)
/**
* ClutterParamSpecFixed