| /************************************************************************** |
| * |
| * Copyright 2010, VMware, inc. |
| * All Rights Reserved. |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the |
| * "Software"), to deal in the Software without restriction, including |
| * without limitation the rights to use, copy, modify, merge, publish, |
| * distribute, sub license, and/or sell copies of the Software, and to |
| * permit persons to whom the Software is furnished to do so, subject to |
| * the following conditions: |
| * |
| * The above copyright notice and this permission notice (including the |
| * next paragraph) shall be included in all copies or substantial portions |
| * of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS |
| * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. |
| * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR |
| * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, |
| * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE |
| * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| * |
| **************************************************************************/ |
| |
| #include "util/u_bitcast.h" |
| #include <math.h> |
| |
| static boolean |
| TAG(do_cliptest)(struct pt_post_vs *pvs, |
| struct draw_vertex_info *info, |
| const struct draw_prim_info *prim_info) |
| { |
| struct vertex_header *out = info->verts; |
| /* const */ float (*plane)[4] = pvs->draw->plane; |
| const unsigned pos = draw_current_shader_position_output(pvs->draw); |
| const unsigned cv = draw_current_shader_clipvertex_output(pvs->draw); |
| const unsigned ef = pvs->draw->vs.edgeflag_output; |
| unsigned ucp_enable = pvs->draw->rasterizer->clip_plane_enable; |
| unsigned flags = (FLAGS); |
| unsigned need_pipeline = 0; |
| bool have_cd = false; |
| bool uses_vp_idx = draw_current_shader_uses_viewport_index(pvs->draw); |
| unsigned viewport_index_output = |
| draw_current_shader_viewport_index_output(pvs->draw); |
| int viewport_index = 0; |
| int num_written_clipdistance = |
| draw_current_shader_num_written_clipdistances(pvs->draw); |
| |
| if (uses_vp_idx) { |
| viewport_index = u_bitcast_f2u(out->data[viewport_index_output][0]); |
| viewport_index = draw_clamp_viewport_idx(viewport_index); |
| } |
| |
| unsigned cd[2]; |
| cd[0] = draw_current_shader_ccdistance_output(pvs->draw, 0); |
| cd[1] = draw_current_shader_ccdistance_output(pvs->draw, 1); |
| if (cd[0] != pos || cd[1] != pos) |
| 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)) { |
| flags |= DO_CLIP_USER; |
| ucp_enable = (1 << num_written_clipdistance) - 1; |
| } |
| |
| assert(pos != -1); |
| unsigned prim_idx = 0, prim_vert_idx = 0; |
| for (unsigned j = 0; j < info->count; j++) { |
| float *position = out->data[pos]; |
| unsigned mask = 0x0; |
| |
| if (uses_vp_idx) { |
| /* only change the viewport_index for the leading vertex */ |
| if (prim_vert_idx == (prim_info->primitive_lengths[prim_idx])) { |
| prim_idx++; |
| prim_vert_idx = 0; |
| viewport_index = u_bitcast_f2u(out->data[viewport_index_output][0]); |
| viewport_index = draw_clamp_viewport_idx(viewport_index); |
| } |
| prim_vert_idx++; |
| } |
| float *scale = pvs->draw->viewports[viewport_index].scale; |
| float *trans = pvs->draw->viewports[viewport_index].translate; |
| initialize_vertex_header(out); |
| |
| if (flags & (DO_CLIP_XY | DO_CLIP_XY_GUARD_BAND | |
| DO_CLIP_FULL_Z | DO_CLIP_HALF_Z | DO_CLIP_USER)) { |
| float *clipvertex = position; |
| |
| if ((flags & DO_CLIP_USER) && cv != pos) { |
| assert(cv != -1); |
| clipvertex = out->data[cv]; |
| } |
| |
| for (unsigned i = 0; i < 4; i++) { |
| out->clip_pos[i] = position[i]; |
| } |
| |
| /* Be careful with NaNs. Comparisons must be true for them. */ |
| /* Do the hardwired planes first: |
| */ |
| if (flags & DO_CLIP_XY_GUARD_BAND) { |
| if (!(-0.50 * position[0] + position[3] >= 0)) mask |= (1<<0); |
| if (!( 0.50 * position[0] + position[3] >= 0)) mask |= (1<<1); |
| if (!(-0.50 * position[1] + position[3] >= 0)) mask |= (1<<2); |
| if (!( 0.50 * position[1] + position[3] >= 0)) mask |= (1<<3); |
| } else if (flags & DO_CLIP_XY) { |
| if (!(-position[0] + position[3] >= 0)) mask |= (1<<0); |
| if (!( position[0] + position[3] >= 0)) mask |= (1<<1); |
| if (!(-position[1] + position[3] >= 0)) mask |= (1<<2); |
| if (!( position[1] + position[3] >= 0)) mask |= (1<<3); |
| } |
| |
| /* Clip Z planes according to full cube, half cube or none. |
| */ |
| if (flags & DO_CLIP_FULL_Z) { |
| if (!( position[2] + position[3] >= 0)) mask |= (1<<4); |
| if (!(-position[2] + position[3] >= 0)) mask |= (1<<5); |
| } else if (flags & DO_CLIP_HALF_Z) { |
| if (!( position[2] >= 0)) mask |= (1<<4); |
| if (!(-position[2] + position[3] >= 0)) mask |= (1<<5); |
| } |
| |
| if (flags & DO_CLIP_USER) { |
| unsigned ucp_mask = ucp_enable; |
| |
| while (ucp_mask) { |
| unsigned plane_idx = ffs(ucp_mask)-1; |
| ucp_mask &= ~(1 << plane_idx); |
| plane_idx += 6; |
| |
| /* |
| * for user clipping check if we have a clip distance output |
| * and the shader has written to it, otherwise use clipvertex |
| * to decide when the plane is clipping. |
| */ |
| if (have_cd && num_written_clipdistance) { |
| float clipdist; |
| unsigned i = plane_idx - 6; |
| /* first four clip distance in first vector etc. */ |
| if (i < 4) |
| clipdist = out->data[cd[0]][i]; |
| else |
| clipdist = out->data[cd[1]][i-4]; |
| if (clipdist < 0 || util_is_inf_or_nan(clipdist)) |
| mask |= 1 << plane_idx; |
| } else { |
| if (!(dot4(clipvertex, plane[plane_idx]) >= 0)) |
| mask |= 1 << plane_idx; |
| } |
| } |
| } |
| |
| out->clipmask = mask; |
| need_pipeline |= out->clipmask; |
| } |
| |
| /* |
| * Transform the vertex position from clip coords to window coords, |
| * if the vertex is unclipped. |
| */ |
| if ((flags & DO_VIEWPORT) && mask == 0) { |
| /* divide by w */ |
| float w = 1.0f / position[3]; |
| |
| /* Viewport mapping */ |
| position[0] = position[0] * w * scale[0] + trans[0]; |
| position[1] = position[1] * w * scale[1] + trans[1]; |
| position[2] = position[2] * w * scale[2] + trans[2]; |
| position[3] = w; |
| } |
| #ifdef DEBUG |
| /* For debug builds, set the clipped vertex's window coordinate |
| * to NaN to help catch potential errors later. |
| */ |
| else { |
| position[0] = |
| position[1] = |
| position[2] = |
| position[3] = NAN; |
| } |
| #endif |
| |
| if ((flags & DO_EDGEFLAG) && ef) { |
| const float *edgeflag = out->data[ef]; |
| out->edgeflag = !(edgeflag[0] != 1.0f); |
| need_pipeline |= !out->edgeflag; |
| } |
| |
| out = (struct vertex_header *)((char *)out + info->stride); |
| } |
| |
| return need_pipeline != 0; |
| } |
| |
| |
| #undef FLAGS |
| #undef TAG |
