fdo-mirrors/mesa
1
0
Fork 0
mirror of https://gitlab.freedesktop.org/mesa/mesa.git synced 2026-04-30 21:21:39 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions 5

Add detailed comments.

Browse source
This commit is contained in:
Michal Krol 2007-10-29 17:36:20 +00:00
parent 7de874ec2c
commit da9815e17f
1 changed files with 86 additions and 16 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

102
src/mesa/pipe/p_format.h
View file

@ -30,25 +30,18 @@
#include "p_compiler.h"
/**
* The PIPE_FORMAT is a 32-bit wide bitfield that encodes all the information
* needed to uniquely describe a pixel format.
*/
/**
* Possible format layouts -- occupy first 2 bits. The interpretation of
* the remaining 30 bits depends on a particual format layout.
*/
#define PIPE_FORMAT_LAYOUT_RGBAZS 0
#define PIPE_FORMAT_LAYOUT_YCBCR 1
#define PIPE_FORMAT_COMP_R 0
#define PIPE_FORMAT_COMP_G 1
#define PIPE_FORMAT_COMP_B 2
#define PIPE_FORMAT_COMP_A 3
#define PIPE_FORMAT_COMP_0 4
#define PIPE_FORMAT_COMP_1 5
#define PIPE_FORMAT_COMP_Z 6
#define PIPE_FORMAT_COMP_S 7
#define PIPE_FORMAT_TYPE_UNKNOWN 0
#define PIPE_FORMAT_TYPE_FLOAT 1
#define PIPE_FORMAT_TYPE_UNORM 2
#define PIPE_FORMAT_TYPE_SNORM 3
#define PIPE_FORMAT_TYPE_USCALED 4
#define PIPE_FORMAT_TYPE_SSCALED 5
struct pipe_format_header
{
uint layout : 2; /**< PIPE_FORMAT_LAYOUT_ */
@ -58,6 +51,48 @@ struct pipe_format_header
/**
* RGBAZS Format Layout.
*/
/**
* Format component selectors for RGBAZS layout.
*/
#define PIPE_FORMAT_COMP_R 0
#define PIPE_FORMAT_COMP_G 1
#define PIPE_FORMAT_COMP_B 2
#define PIPE_FORMAT_COMP_A 3
#define PIPE_FORMAT_COMP_0 4
#define PIPE_FORMAT_COMP_1 5
#define PIPE_FORMAT_COMP_Z 6
#define PIPE_FORMAT_COMP_S 7
/**
* Format types for RGBAZS layout.
*/
#define PIPE_FORMAT_TYPE_UNKNOWN 0
#define PIPE_FORMAT_TYPE_FLOAT 1
#define PIPE_FORMAT_TYPE_UNORM 2
#define PIPE_FORMAT_TYPE_SNORM 3
#define PIPE_FORMAT_TYPE_USCALED 4
#define PIPE_FORMAT_TYPE_SSCALED 5
/**
* In a nutshell, this bitfield contains instructions how to unpack
* a given format to a full-blown 4-component vector suitable for FS.
* Because the destination vector is assumed to be RGBA FLOAT, we
* need to know how to swizzle and expand components from the source
* vector.
* Let's take U_A1_R5_G5_B5 as an example. SwizzleX is A, sizeX
* is 1 bit and type is UNORM. So we take the most significant bit
* from source vector, convert 0 to 0.0 and 1 to 1.0 and save it
* in the last component of the destination RGBA component.
* Next, swizzleY is R, sizeY is 5 and type is UNORM. We normalize
* those 5 bits into [0.0; 1.0] range and put it into second
* component of the destination vector. Rinse and repeat for
* components Z and W.
* If any of size fields is zero, it means the source format contains
* less than four components.
* If any swizzle is 0 or 1, the corresponding destination component
* should be filled with 0.0 and 1.0, respectively.
*/
struct pipe_format_rgbazs
{
uint layout : 2; /**< PIPE_FORMAT_LAYOUT_RGBAZS */
@ -74,6 +109,9 @@ struct pipe_format_rgbazs
uint padding : 1;
};
/**
* Helper macro to encode the above structure into a 32-bit value.
*/
#define _PIPE_FORMAT_RGBAZS( SWZ, SIZEX, SIZEY, SIZEZ, SIZEW, EXP8, TYPE ) (\
(PIPE_FORMAT_LAYOUT_RGBAZS << 0) |\
((SWZ) << 2) |\
@ -84,23 +122,44 @@ struct pipe_format_rgbazs
((EXP8) << 26) |\
((TYPE) << 28) )
/**
* Helper macro to encode the swizzle part of the structure above.
*/
#define _PIPE_FORMAT_SWZ( SWZX, SWZY, SWZZ, SWZW ) (((SWZX) << 0) | ((SWZY) << 3) | ((SWZZ) << 6) | ((SWZW) << 9))
/**
* Shorthand macro for RGBAZS layout with uniform component sizes in 1-bit units.
*/
#define _PIPE_FORMAT_RGBAZS_1U( SWZ, SIZE, TYPE )\
_PIPE_FORMAT_RGBAZS( SWZ, SIZE, SIZE, SIZE, SIZE, 0, TYPE )
/**
* Shorthand macro for RGBAZS layout with non-uniform component sizes in 1-bit units.
*/
#define _PIPE_FORMAT_RGBAZS_1N( SWZ, SIZEX, SIZEY, SIZEZ, SIZEW, TYPE )\
_PIPE_FORMAT_RGBAZS( SWZ, SIZEX, SIZEY, SIZEZ, SIZEW, 0, TYPE )
/**
* Shorthand macro for RGBAZS layout with uniform component sizes in 8-bit units.
*/
#define _PIPE_FORMAT_RGBAZS_8U( SWZ, SIZE, TYPE )\
_PIPE_FORMAT_RGBAZS( SWZ, SIZE, SIZE, SIZE, SIZE, 1, TYPE )
/**
* Shorthand macro for RGBAZS layout with non-uniform component sizes in 8-bit units.
*/
#define _PIPE_FORMAT_RGBAZS_8N( SWZ, SIZEX, SIZEY, SIZEZ, SIZEW, TYPE )\
_PIPE_FORMAT_RGBAZS( SWZ, SIZEX, SIZEY, SIZEZ, SIZEW, 1, TYPE )
/**
* Shorthand macro for RGBAZS layout with non-uniform component sizes in 64-bit units.
*/
#define _PIPE_FORMAT_RGBAZS_64( SWZ, SIZEX, SIZEY, SIZEZ, SIZEW, TYPE )\
_PIPE_FORMAT_RGBAZS( SWZ, SIZEX, SIZEY, SIZEZ, SIZEW, 2, TYPE )
/**
* Shorthand macro for common format swizzles.
*/
#define _PIPE_FORMAT_R000 _PIPE_FORMAT_SWZ( PIPE_FORMAT_COMP_R, PIPE_FORMAT_COMP_0, PIPE_FORMAT_COMP_0, PIPE_FORMAT_COMP_0 )
#define _PIPE_FORMAT_RG00 _PIPE_FORMAT_SWZ( PIPE_FORMAT_COMP_R, PIPE_FORMAT_COMP_0, PIPE_FORMAT_COMP_0, PIPE_FORMAT_COMP_A )
#define _PIPE_FORMAT_RGB0 _PIPE_FORMAT_SWZ( PIPE_FORMAT_COMP_R, PIPE_FORMAT_COMP_0, PIPE_FORMAT_COMP_B, PIPE_FORMAT_COMP_A )
@ -115,6 +174,14 @@ struct pipe_format_rgbazs
#define _PIPE_FORMAT_SZ00 _PIPE_FORMAT_SWZ( PIPE_FORMAT_COMP_S, PIPE_FORMAT_COMP_Z, PIPE_FORMAT_COMP_0, PIPE_FORMAT_COMP_0 )
#define _PIPE_FORMAT_S000 _PIPE_FORMAT_SWZ( PIPE_FORMAT_COMP_S, PIPE_FORMAT_COMP_0, PIPE_FORMAT_COMP_0, PIPE_FORMAT_COMP_0 )
/**
* YCBCR Format Layout.
*/
/**
* This bitfields is simple. It only contains a flag that indicates whether the
* format is reversed or not.
*/
struct pipe_format_ycbcr
{
uint layout : 2; /**< PIPE_FORMAT_LAYOUT_YCBCR */
@ -122,6 +189,9 @@ struct pipe_format_ycbcr
uint padding : 29;
};
/**
* Helper macro to encode the above structure into a 32-bit value.
*/
#define _PIPE_FORMAT_YCBCR( REV ) (\
(PIPE_FORMAT_LAYOUT_YCBCR << 0) |\
((REV) << 2) )