1 /************************************************************************** 2 * 3 * Copyright 2010, VMware, inc. 4 * All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sub license, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the 15 * next paragraph) shall be included in all copies or substantial portions 16 * of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. 21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR 22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 25 * 26 **************************************************************************/ 27 28 #include "util/u_bitcast.h" 29 30 static boolean TAG(do_cliptest)( struct pt_post_vs *pvs, 31 struct draw_vertex_info *info, 32 const struct draw_prim_info *prim_info ) 33 { 34 struct vertex_header *out = info->verts; 35 /* const */ float (*plane)[4] = pvs->draw->plane; 36 const unsigned pos = draw_current_shader_position_output(pvs->draw); 37 const unsigned cv = draw_current_shader_clipvertex_output(pvs->draw); 38 unsigned cd[2]; 39 const unsigned ef = pvs->draw->vs.edgeflag_output; 40 unsigned ucp_enable = pvs->draw->rasterizer->clip_plane_enable; 41 unsigned flags = (FLAGS); 42 unsigned need_pipeline = 0; 43 unsigned j; 44 unsigned i; 45 bool have_cd = false; 46 unsigned viewport_index_output = 47 draw_current_shader_viewport_index_output(pvs->draw); 48 int viewport_index = 49 draw_current_shader_uses_viewport_index(pvs->draw) ? 50 u_bitcast_f2u(out->data[viewport_index_output][0]): 0; 51 int num_written_clipdistance = 52 draw_current_shader_num_written_clipdistances(pvs->draw); 53 54 cd[0] = draw_current_shader_ccdistance_output(pvs->draw, 0); 55 cd[1] = draw_current_shader_ccdistance_output(pvs->draw, 1); 56 57 if (cd[0] != pos || cd[1] != pos) 58 have_cd = true; 59 60 /* If clipdistance semantic has been written by the shader 61 * that means we're expected to do 'user plane clipping' */ 62 if (num_written_clipdistance && !(flags & DO_CLIP_USER)) { 63 flags |= DO_CLIP_USER; 64 ucp_enable = (1 << num_written_clipdistance) - 1; 65 } 66 67 assert(pos != -1); 68 for (j = 0; j < info->count; j++) { 69 float *position = out->data[pos]; 70 unsigned mask = 0x0; 71 float *scale = pvs->draw->viewports[0].scale; 72 float *trans = pvs->draw->viewports[0].translate; 73 if (draw_current_shader_uses_viewport_index(pvs->draw)) { 74 unsigned verts_per_prim = u_vertices_per_prim(prim_info->prim); 75 /* only change the viewport_index for the leading vertex */ 76 if (!(j % verts_per_prim)) { 77 viewport_index = u_bitcast_f2u(out->data[viewport_index_output][0]); 78 viewport_index = draw_clamp_viewport_idx(viewport_index); 79 } 80 scale = pvs->draw->viewports[viewport_index].scale; 81 trans = pvs->draw->viewports[viewport_index].translate; 82 } 83 84 initialize_vertex_header(out); 85 86 if (flags & (DO_CLIP_XY | DO_CLIP_XY_GUARD_BAND | 87 DO_CLIP_FULL_Z | DO_CLIP_HALF_Z | DO_CLIP_USER)) { 88 float *clipvertex = position; 89 90 if ((flags & DO_CLIP_USER) && cv != pos) { 91 assert(cv != -1); 92 clipvertex = out->data[cv]; 93 } 94 95 for (i = 0; i < 4; i++) { 96 out->clip_pos[i] = position[i]; 97 } 98 99 /* Be careful with NaNs. Comparisons must be true for them. */ 100 /* Do the hardwired planes first: 101 */ 102 if (flags & DO_CLIP_XY_GUARD_BAND) { 103 if (!(-0.50 * position[0] + position[3] >= 0)) mask |= (1<<0); 104 if (!( 0.50 * position[0] + position[3] >= 0)) mask |= (1<<1); 105 if (!(-0.50 * position[1] + position[3] >= 0)) mask |= (1<<2); 106 if (!( 0.50 * position[1] + position[3] >= 0)) mask |= (1<<3); 107 } 108 else if (flags & DO_CLIP_XY) { 109 if (!(-position[0] + position[3] >= 0)) mask |= (1<<0); 110 if (!( position[0] + position[3] >= 0)) mask |= (1<<1); 111 if (!(-position[1] + position[3] >= 0)) mask |= (1<<2); 112 if (!( position[1] + position[3] >= 0)) mask |= (1<<3); 113 } 114 115 /* Clip Z planes according to full cube, half cube or none. 116 */ 117 if (flags & DO_CLIP_FULL_Z) { 118 if (!( position[2] + position[3] >= 0)) mask |= (1<<4); 119 if (!(-position[2] + position[3] >= 0)) mask |= (1<<5); 120 } 121 else if (flags & DO_CLIP_HALF_Z) { 122 if (!( position[2] >= 0)) mask |= (1<<4); 123 if (!(-position[2] + position[3] >= 0)) mask |= (1<<5); 124 } 125 126 if (flags & DO_CLIP_USER) { 127 unsigned ucp_mask = ucp_enable; 128 129 while (ucp_mask) { 130 unsigned plane_idx = ffs(ucp_mask)-1; 131 ucp_mask &= ~(1 << plane_idx); 132 plane_idx += 6; 133 134 /* 135 * for user clipping check if we have a clip distance output 136 * and the shader has written to it, otherwise use clipvertex 137 * to decide when the plane is clipping. 138 */ 139 if (have_cd && num_written_clipdistance) { 140 float clipdist; 141 i = plane_idx - 6; 142 /* first four clip distance in first vector etc. */ 143 if (i < 4) 144 clipdist = out->data[cd[0]][i]; 145 else 146 clipdist = out->data[cd[1]][i-4]; 147 if (clipdist < 0 || util_is_inf_or_nan(clipdist)) 148 mask |= 1 << plane_idx; 149 } else { 150 if (!(dot4(clipvertex, plane[plane_idx]) >= 0)) 151 mask |= 1 << plane_idx; 152 } 153 } 154 } 155 156 out->clipmask = mask; 157 need_pipeline |= out->clipmask; 158 } 159 160 /* 161 * Transform the vertex position from clip coords to window coords, 162 * if the vertex is unclipped. 163 */ 164 if ((flags & DO_VIEWPORT) && mask == 0) 165 { 166 /* divide by w */ 167 float w = 1.0f / position[3]; 168 169 /* Viewport mapping */ 170 position[0] = position[0] * w * scale[0] + trans[0]; 171 position[1] = position[1] * w * scale[1] + trans[1]; 172 position[2] = position[2] * w * scale[2] + trans[2]; 173 position[3] = w; 174 } 175 #ifdef DEBUG 176 /* For debug builds, set the clipped vertex's window coordinate 177 * to NaN to help catch potential errors later. 178 */ 179 else { 180 float zero = 0.0f; 181 position[0] = 182 position[1] = 183 position[2] = 184 position[3] = zero / zero; /* MSVC doesn't accept 0.0 / 0.0 */ 185 } 186 #endif 187 188 if ((flags & DO_EDGEFLAG) && ef) { 189 const float *edgeflag = out->data[ef]; 190 out->edgeflag = !(edgeflag[0] != 1.0f); 191 need_pipeline |= !out->edgeflag; 192 } 193 194 out = (struct vertex_header *)( (char *)out + info->stride ); 195 } 196 return need_pipeline != 0; 197 } 198 199 200 #undef FLAGS 201 #undef TAG 202
