On 06/10/2013 08:31 AM, Zack Rusin wrote:
Draw depended on clip_plane_enable being set in the rasterizer to use clipdistance registers for clipping. That's really unfriendly because it requires that rasterizer state to have variants for every shader out there. Instead of depending on the rasterizer lets extract the info from the available state: if a shader writes clipdistance then we need to use it and we need to clip using a number of planes equal to the number of writen clipdistance components. This way clipdistances just work.
Is this a gallium interface policy that should be documented?
Signed-off-by: Zack Rusin <za...@vmware.com> --- src/gallium/auxiliary/draw/draw_cliptest_tmp.h | 21 ++++++++++++++++----- src/gallium/auxiliary/draw/draw_llvm.c | 8 ++++++++ 2 files changed, 24 insertions(+), 5 deletions(-) diff --git a/src/gallium/auxiliary/draw/draw_cliptest_tmp.h b/src/gallium/auxiliary/draw/draw_cliptest_tmp.h index 7a385c8..6736dba 100644 --- a/src/gallium/auxiliary/draw/draw_cliptest_tmp.h +++ b/src/gallium/auxiliary/draw/draw_cliptest_tmp.h @@ -35,8 +35,8 @@ static boolean TAG(do_cliptest)( struct pt_post_vs *pvs, const unsigned cv = draw_current_shader_clipvertex_output(pvs->draw); unsigned cd[2]; const unsigned ef = pvs->draw->vs.edgeflag_output; - const unsigned ucp_enable = pvs->draw->rasterizer->clip_plane_enable; - const unsigned flags = (FLAGS); + unsigned ucp_enable = pvs->draw->rasterizer->clip_plane_enable; + unsigned flags = (FLAGS); unsigned need_pipeline = 0; unsigned j; unsigned i; @@ -46,12 +46,24 @@ static boolean TAG(do_cliptest)( struct pt_post_vs *pvs, int viewport_index = draw_current_shader_uses_viewport_index(pvs->draw) ? *((unsigned*)out->data[viewport_index_output]): 0; + int num_written_clipdistance = + draw_current_shader_num_written_clipdistances(pvs->draw); cd[0] = draw_current_shader_clipdistance_output(pvs->draw, 0); cd[1] = draw_current_shader_clipdistance_output(pvs->draw, 1); if (cd[0] != pos || cd[1] != pos) - have_cd = true; + have_cd = true; + + /* If clipdistance semantic has been written by the shader + * that means we're expected to do 'user plane clipping' */ + if (num_written_clipdistance && !(flags & DO_CLIP_USER)) { + unsigned i; + flags |= DO_CLIP_USER; + ucp_enable = 0; + for (i = 0; i < num_written_clipdistance; ++i) + ucp_enable |= 1 << i; + } for (j = 0; j < info->count; j++) { float *position = out->data[pos]; @@ -111,8 +123,7 @@ static boolean TAG(do_cliptest)( struct pt_post_vs *pvs, if (flags & DO_CLIP_USER) { unsigned ucp_mask = ucp_enable; - int num_written_clipdistance = - draw_current_shader_num_written_clipdistances(pvs->draw); + while (ucp_mask) { unsigned plane_idx = ffs(ucp_mask)-1; ucp_mask &= ~(1 << plane_idx); diff --git a/src/gallium/auxiliary/draw/draw_llvm.c b/src/gallium/auxiliary/draw/draw_llvm.c index 4a71955..82f4c20 100644 --- a/src/gallium/auxiliary/draw/draw_llvm.c +++ b/src/gallium/auxiliary/draw/draw_llvm.c @@ -1146,6 +1146,14 @@ generate_clipmask(struct draw_llvm *llvm, if (cd[0] != pos || cd[1] != pos) have_cd = true; + if (num_written_clipdistance && !clip_user) { + unsigned i; + clip_user = true; + ucp_enable = 0; + for (i = 0; i < num_written_clipdistance; ++i) + ucp_enable |= 1 << i;
I think this can be done without a loop: ucp_enable = (1 << num_written_clipdistance) - 1; Same thing earlier in the code.
+ } + mask = lp_build_const_int_vec(gallivm, i32_type, 0); temp = lp_build_const_int_vec(gallivm, i32_type, 0); zero = lp_build_const_vec(gallivm, f32_type, 0); /* 0.0f 0.0f 0.0f 0.0f */
Reviewed-by: Brian Paul <bri...@vmware.com> _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev