1 /* 2 * Copyright 2010 Marek Olk <maraeo (at) gmail.com> 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * on the rights to use, copy, modify, merge, publish, distribute, sub 8 * license, and/or sell copies of the Software, and to permit persons to whom 9 * the Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM, 19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 20 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 21 * USE OR OTHER DEALINGS IN THE SOFTWARE. */ 22 23 /** 24 * The two-sided stencil reference value fallback for r3xx-r4xx chips. 25 * These chips support two-sided stencil functions but they do not support 26 * a two-sided reference value. 27 * 28 * The functions below split every draw call which uses the two-sided 29 * reference value into two draw calls -- the first one renders front faces 30 * and the second renders back faces with the other reference value. 31 */ 32 33 #include "r300_context.h" 34 #include "r300_reg.h" 35 36 struct r300_stencilref_context { 37 void (*draw_vbo)(struct pipe_context *pipe, 38 const struct pipe_draw_info *info); 39 40 uint32_t rs_cull_mode; 41 uint32_t zb_stencilrefmask; 42 ubyte ref_value_front; 43 }; 44 45 static boolean r300_stencilref_needed(struct r300_context *r300) 46 { 47 struct r300_dsa_state *dsa = (struct r300_dsa_state*)r300->dsa_state.state; 48 49 return dsa->two_sided_stencil_ref || 50 (dsa->two_sided && 51 r300->stencil_ref.ref_value[0] != r300->stencil_ref.ref_value[1]); 52 } 53 54 /* Set drawing for front faces. */ 55 static void r300_stencilref_begin(struct r300_context *r300) 56 { 57 struct r300_stencilref_context *sr = r300->stencilref_fallback; 58 struct r300_rs_state *rs = (struct r300_rs_state*)r300->rs_state.state; 59 struct r300_dsa_state *dsa = (struct r300_dsa_state*)r300->dsa_state.state; 60 61 /* Save state. */ 62 sr->rs_cull_mode = rs->cb_main[rs->cull_mode_index]; 63 sr->zb_stencilrefmask = dsa->stencil_ref_mask; 64 sr->ref_value_front = r300->stencil_ref.ref_value[0]; 65 66 /* We *cull* pixels, therefore no need to mask out the bits. */ 67 rs->cb_main[rs->cull_mode_index] |= R300_CULL_BACK; 68 69 r300_mark_atom_dirty(r300, &r300->rs_state); 70 } 71 72 /* Set drawing for back faces. */ 73 static void r300_stencilref_switch_side(struct r300_context *r300) 74 { 75 struct r300_stencilref_context *sr = r300->stencilref_fallback; 76 struct r300_rs_state *rs = (struct r300_rs_state*)r300->rs_state.state; 77 struct r300_dsa_state *dsa = (struct r300_dsa_state*)r300->dsa_state.state; 78 79 rs->cb_main[rs->cull_mode_index] = sr->rs_cull_mode | R300_CULL_FRONT; 80 dsa->stencil_ref_mask = dsa->stencil_ref_bf; 81 r300->stencil_ref.ref_value[0] = r300->stencil_ref.ref_value[1]; 82 83 r300_mark_atom_dirty(r300, &r300->rs_state); 84 r300_mark_atom_dirty(r300, &r300->dsa_state); 85 } 86 87 /* Restore the original state. */ 88 static void r300_stencilref_end(struct r300_context *r300) 89 { 90 struct r300_stencilref_context *sr = r300->stencilref_fallback; 91 struct r300_rs_state *rs = (struct r300_rs_state*)r300->rs_state.state; 92 struct r300_dsa_state *dsa = (struct r300_dsa_state*)r300->dsa_state.state; 93 94 /* Restore state. */ 95 rs->cb_main[rs->cull_mode_index] = sr->rs_cull_mode; 96 dsa->stencil_ref_mask = sr->zb_stencilrefmask; 97 r300->stencil_ref.ref_value[0] = sr->ref_value_front; 98 99 r300_mark_atom_dirty(r300, &r300->rs_state); 100 r300_mark_atom_dirty(r300, &r300->dsa_state); 101 } 102 103 static void r300_stencilref_draw_vbo(struct pipe_context *pipe, 104 const struct pipe_draw_info *info) 105 { 106 struct r300_context *r300 = r300_context(pipe); 107 struct r300_stencilref_context *sr = r300->stencilref_fallback; 108 109 if (!r300_stencilref_needed(r300)) { 110 sr->draw_vbo(pipe, info); 111 } else { 112 r300_stencilref_begin(r300); 113 sr->draw_vbo(pipe, info); 114 r300_stencilref_switch_side(r300); 115 sr->draw_vbo(pipe, info); 116 r300_stencilref_end(r300); 117 } 118 } 119 120 void r300_plug_in_stencil_ref_fallback(struct r300_context *r300) 121 { 122 r300->stencilref_fallback = CALLOC_STRUCT(r300_stencilref_context); 123 124 /* Save original draw function. */ 125 r300->stencilref_fallback->draw_vbo = r300->context.draw_vbo; 126 127 /* Override the draw function. */ 128 r300->context.draw_vbo = r300_stencilref_draw_vbo; 129 } 130
