[Mesa-dev] [PATCH 7/8] gallium: create TGSI_PROPERTY to disable viewport and clipping
Marek Olšák
maraeo at gmail.com
Wed May 21 04:15:29 PDT 2014
Now I understand. Yes, I'll add a CAP.
Marek
On Wed, May 21, 2014 at 1:11 PM, Roland Scheidegger <sroland at vmware.com> wrote:
> Yes but I'm saying you need to translate it away in the state tracker, cause
> you can't really require all drivers to implement it, because this is a
> feature where I really don't think you can say it's the drivers fault if
> it's not implemented.
>
> Roland
>
>
> On 05/21/2014 11:54 AM, Marek Olšák wrote:
>>
>> We don't translate it away. The property does 2 things not available
>> in the pipe interface:
>> - It disables viewport clipping, so that window coordinates can pass
>> through untouched.
>> - It disables viewport transformation.
>>
>> Our hardware is capable of both, however, some APIs are not.
>>
>> Marek
>>
>> On Wed, May 21, 2014 at 12:42 PM, Roland Scheidegger <sroland at vmware.com>
>> wrote:
>>>
>>> On 05/21/2014 12:49 AM, Marek Olšák wrote:
>>>>
>>>>
>>>> Hi,
>>>>
>>>> Could somebody from VMWare please review this patch? It's for st/nine
>>>> (open d3d9 state tracker).
>>>>
>>>> Thanks,
>>>>
>>>> Marek
>>>>
>>>> On Sat, May 17, 2014 at 1:20 AM, Automated rebase
>>>> <david.heidelberger at ixit.cz> wrote:
>>>>>
>>>>>
>>>>> From: Christoph Bumiller <e0425955 at student.tuwien.ac.at>
>>>>>
>>>>> ---
>>>>> src/gallium/auxiliary/tgsi/tgsi_strings.c | 3 ++-
>>>>> src/gallium/auxiliary/tgsi/tgsi_ureg.c | 16 ++++++++++++++++
>>>>> src/gallium/auxiliary/tgsi/tgsi_ureg.h | 4 ++++
>>>>> src/gallium/docs/source/tgsi.rst | 9 +++++++++
>>>>> src/gallium/include/pipe/p_shader_tokens.h | 3 ++-
>>>>> 5 files changed, 33 insertions(+), 2 deletions(-)
>>>>>
>>>>> diff --git a/src/gallium/auxiliary/tgsi/tgsi_strings.c
>>>>> b/src/gallium/auxiliary/tgsi/tgsi_strings.c
>>>>> index 5b6e47f..c3e7118 100644
>>>>> --- a/src/gallium/auxiliary/tgsi/tgsi_strings.c
>>>>> +++ b/src/gallium/auxiliary/tgsi/tgsi_strings.c
>>>>> @@ -120,7 +120,8 @@ const char
>>>>> *tgsi_property_names[TGSI_PROPERTY_COUNT]
>>>>> =
>>>>> "FS_COORD_PIXEL_CENTER",
>>>>> "FS_COLOR0_WRITES_ALL_CBUFS",
>>>>> "FS_DEPTH_LAYOUT",
>>>>> - "VS_PROHIBIT_UCPS"
>>>>> + "VS_PROHIBIT_UCPS",
>>>>> + "VS_POSITION_WINDOW_SPACE"
>>>>> };
>>>>>
>>>>> const char *tgsi_type_names[5] =
>>>>> diff --git a/src/gallium/auxiliary/tgsi/tgsi_ureg.c
>>>>> b/src/gallium/auxiliary/tgsi/tgsi_ureg.c
>>>>> index 2bf93ee..bd0a3f7 100644
>>>>> --- a/src/gallium/auxiliary/tgsi/tgsi_ureg.c
>>>>> +++ b/src/gallium/auxiliary/tgsi/tgsi_ureg.c
>>>>> @@ -173,6 +173,7 @@ struct ureg_program
>>>>> unsigned char property_fs_coord_pixel_center; /* =
>>>>> TGSI_FS_COORD_PIXEL_CENTER_* */
>>>>> unsigned char property_fs_color0_writes_all_cbufs; /* =
>>>>> TGSI_FS_COLOR0_WRITES_ALL_CBUFS * */
>>>>> unsigned char property_fs_depth_layout; /* TGSI_FS_DEPTH_LAYOUT
>>>>> */
>>>>> + boolean property_vs_window_space_position; /*
>>>>> TGSI_VS_WINDOW_SPACE_POSITION */
>>>>>
>>>>> unsigned nr_addrs;
>>>>> unsigned nr_preds;
>>>>> @@ -331,6 +332,13 @@ ureg_property_fs_depth_layout(struct ureg_program
>>>>> *ureg,
>>>>> ureg->property_fs_depth_layout = fs_depth_layout;
>>>>> }
>>>>>
>>>>> +void
>>>>> +ureg_property_vs_window_space_position(struct ureg_program *ureg,
>>>>> + boolean
>>>>> vs_window_space_position)
>>>>> +{
>>>>> + ureg->property_vs_window_space_position = vs_window_space_position;
>>>>> +}
>>>>> +
>>>>> struct ureg_src
>>>>> ureg_DECL_fs_input_cyl_centroid(struct ureg_program *ureg,
>>>>> unsigned semantic_name,
>>>>> @@ -1508,6 +1516,14 @@ static void emit_decls( struct ureg_program
>>>>> *ureg
>>>>> )
>>>>> ureg->property_fs_depth_layout);
>>>>> }
>>>>>
>>>>> + if (ureg->property_vs_window_space_position) {
>>>>> + assert(ureg->processor == TGSI_PROCESSOR_VERTEX);
>>>>> +
>>>>> + emit_property(ureg,
>>>>> + TGSI_PROPERTY_VS_WINDOW_SPACE_POSITION,
>>>>> + ureg->property_vs_window_space_position);
>>>>> + }
>>>>> +
>>>>> if (ureg->processor == TGSI_PROCESSOR_VERTEX) {
>>>>> for (i = 0; i < UREG_MAX_INPUT; i++) {
>>>>> if (ureg->vs_inputs[i/32] & (1 << (i%32))) {
>>>>> diff --git a/src/gallium/auxiliary/tgsi/tgsi_ureg.h
>>>>> b/src/gallium/auxiliary/tgsi/tgsi_ureg.h
>>>>> index a0a50b7..28edea6 100644
>>>>> --- a/src/gallium/auxiliary/tgsi/tgsi_ureg.h
>>>>> +++ b/src/gallium/auxiliary/tgsi/tgsi_ureg.h
>>>>> @@ -184,6 +184,10 @@ void
>>>>> ureg_property_fs_depth_layout(struct ureg_program *ureg,
>>>>> unsigned fs_depth_layout);
>>>>>
>>>>> +void
>>>>> +ureg_property_vs_window_space_position(struct ureg_program *ureg,
>>>>> + boolean
>>>>> vs_window_space_position);
>>>>> +
>>>>>
>>>>>
>>>>>
>>>>> /***********************************************************************
>>>>> * Build shader declarations:
>>>>> diff --git a/src/gallium/docs/source/tgsi.rst
>>>>> b/src/gallium/docs/source/tgsi.rst
>>>>> index 9500b9d..2ca3c3b 100644
>>>>> --- a/src/gallium/docs/source/tgsi.rst
>>>>> +++ b/src/gallium/docs/source/tgsi.rst
>>>>> @@ -2848,6 +2848,15 @@ input primitive. Each invocation will have a
>>>>> different
>>>>> TGSI_SEMANTIC_INVOCATIONID system value set. If not specified,
>>>>> assumed
>>>>> to
>>>>> be 1.
>>>>>
>>>>> +VS_WINDOW_SPACE_POSITION
>>>>> +""""""""""""""""""""""""""
>>>>> +If this property is set on the vertex shader, the
>>>>> TGSI_SEMANTIC_POSITION
>>>>> output
>>>>> +is assumed to contain window space coordinates.
>>>>> +Division of X,Y,Z by W and the viewport transformation are disabled,
>>>>> and
>>>>> 1/W is
>>>>> +directly taken from the 4-th component of the shader output.
>>>>> +Naturally, clipping is not performed on window coordinates either.
>>>>> +The effect of this property is undefined if a geometry or tessellation
>>>>> shader
>>>>> +are in use.
>>>>>
>>>>> Texture Sampling and Texture Formats
>>>>> ------------------------------------
>>>>> diff --git a/src/gallium/include/pipe/p_shader_tokens.h
>>>>> b/src/gallium/include/pipe/p_shader_tokens.h
>>>>> index d095bd3..9261b79 100644
>>>>> --- a/src/gallium/include/pipe/p_shader_tokens.h
>>>>> +++ b/src/gallium/include/pipe/p_shader_tokens.h
>>>>> @@ -237,7 +237,8 @@ union tgsi_immediate_data
>>>>> #define TGSI_PROPERTY_FS_DEPTH_LAYOUT 6
>>>>> #define TGSI_PROPERTY_VS_PROHIBIT_UCPS 7
>>>>> #define TGSI_PROPERTY_GS_INVOCATIONS 8
>>>>> -#define TGSI_PROPERTY_COUNT 9
>>>>> +#define TGSI_PROPERTY_VS_WINDOW_SPACE_POSITION 9
>>>>> +#define TGSI_PROPERTY_COUNT 10
>>>>>
>>>>> struct tgsi_property {
>>>>> unsigned Type : 4; /**< TGSI_TOKEN_TYPE_PROPERTY */
>>>>> --
>>>
>>>
>>>
>>> I can't say I'm a big fan of it (I guess alternatively you could use a
>>> TGSI_SEMANTIC_POSITIONT output but that doesn't really make a difference
>>> neither).
>>> This was quite some d3d hack which doesn't really fit into a modern
>>> shader
>>> based world (of course, it doesn't work with d3d10 neither). So, the
>>> usual
>>> way to deal with this is to translate this away, since this was only used
>>> for old or simple stuff afaik (if it was complex you tend to not already
>>> know the screen space coords) noone is going to care if it runs at 1500
>>> or
>>> 1520 fps anyway.
>>> But if you really think this is a must have and are going to use it in a
>>> public state tracker you probably have to implement a cap bit for it too,
>>> and be able to deal with drivers which can't handle it - it seems
>>> unreasonable to me to assume all drivers will handle it (hence you don't
>>> really save anything in the state tracker, you still need all the code
>>> translating it away anyway).
>>>
>>> Roland
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