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author | Juan A. Suarez Romero <[email protected]> | 2016-12-16 10:24:43 +0100 |
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committer | Juan A. Suarez Romero <[email protected]> | 2017-01-09 10:42:22 +0100 |
commit | c2acf97fcc9b32eaa9778771282758e5652a8ad4 (patch) | |
tree | a7c8890b9a6a1532b55170d531310382742cb9de /src/intel/vulkan/genX_cmd_buffer.c | |
parent | 3551a2d3ad2661477ba3b0a36a13eeb68e28fe85 (diff) |
nir/i965: use two slots from inputs_read for dvec3/dvec4 vertex input attributes
So far, input_reads was a bitmap tracking which vertex input locations
were being used.
In OpenGL, an attribute bigger than a vec4 (like a dvec3 or dvec4)
consumes just one location, any other small attribute. So we mark the
proper bit in inputs_read, and also the same bit in double_inputs_read
if the attribute is a dvec3/dvec4.
But in Vulkan, this is slightly different: a dvec3/dvec4 attribute
consumes two locations, not just one. And hence two bits would be marked
in inputs_read for the same vertex input attribute.
To avoid handling two different situations in NIR, we just choose the
latest one: in OpenGL, when creating NIR from GLSL/IR, any dvec3/dvec4
vertex input attribute is marked with two bits in the inputs_read bitmap
(and also in the double_inputs_read), and following attributes are
adjusted accordingly.
As example, if in our GLSL/IR shader we have three attributes:
layout(location = 0) vec3 attr0;
layout(location = 1) dvec4 attr1;
layout(location = 2) dvec3 attr2;
then in our NIR shader we put attr0 in location 0, attr1 in locations 1
and 2, and attr2 in location 3 and 4.
Checking carefully, basically we are using slots rather than locations
in NIR.
When emitting the vertices, we do a inverse map to know the
corresponding location for each slot.
v2 (Jason):
- use two slots from inputs_read for dvec3/dvec4 NIR from GLSL/IR.
v3 (Jason):
- Fix commit log error.
- Use ladder ifs and fix braces.
- elements_double is divisible by 2, don't need DIV_ROUND_UP().
- Use if ladder instead of a switch.
- Add comment about hardware restriction in 64bit vertex attributes.
Reviewed-by: Jason Ekstrand <[email protected]>
Diffstat (limited to 'src/intel/vulkan/genX_cmd_buffer.c')
0 files changed, 0 insertions, 0 deletions