On Tue, Nov 01, 2011 at 05:57:36PM +0800, Yuanhan Liu wrote:
> According to bspec, MIPCnt(was set to intelObj->_MaxLevel) was used for
> min/mag filter mode determination. For a normal case with no mipmap like
> this:
>
> glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
> glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
>
> hardware would always choose mag filter(GL_LINEAR) here since MIPCnt was
> set to 0 zero, then would make LOD be zero. Then according the formula:
> MagMode = (LOD - Base <= 0)
Here are some more comments about this: LOD is a pre-computed value. if
preClamp is enabled, then LOD would be:
LOD = min(min(MIPCnt, MAX_LOD), LOD);
So, if MIPCnt was set to 0, and preClamp was enabled, then the _final_
LOD would be 0, and hardware choose mag filter.
Thoughts?
>
> Thus hardware choose Mag filter.
>
> This would fix all oglc filtercubemin subcase fail
>
> Signed-off-by: Yuanhan Liu <yuanhan....@linux.intel.com>
> ---
> src/mesa/drivers/dri/intel/intel_tex_validate.c | 10 ++++++++--
> 1 files changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/src/mesa/drivers/dri/intel/intel_tex_validate.c
> b/src/mesa/drivers/dri/intel/intel_tex_validate.c
> index e2b8699..c06a043 100644
> --- a/src/mesa/drivers/dri/intel/intel_tex_validate.c
> +++ b/src/mesa/drivers/dri/intel/intel_tex_validate.c
> @@ -21,8 +21,14 @@ intel_update_max_level(struct intel_texture_object
> *intelObj,
> {
> struct gl_texture_object *tObj = &intelObj->base;
>
> - if (sampler->MinFilter == GL_NEAREST ||
> - sampler->MinFilter == GL_LINEAR) {
> + /*
> + * According to Bspec vol5c 1.2.1.5 LOD Computation Pseudocode,
> + * the MIPCnt(here intelObj->_MaxLevel) was used for min/mag
> + * determination.
> + */
Also it seemts that this comments insn't good enough, will update it in
the next patch.
Thanks,
Yuanhan Liu
> + if ((sampler->MinFilter == sampler->MagFilter) &&
> + (sampler->MinFilter == GL_NEAREST ||
> + sampler->MinFilter == GL_LINEAR)) {
> intelObj->_MaxLevel = tObj->BaseLevel;
> } else {
> intelObj->_MaxLevel = tObj->_MaxLevel;
> --
> 1.7.4.4
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/mesa-dev
