src/mesa/state_tracker/st_atom_blend.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2007 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  /*
  29   * Authors:
  30   *   Keith Whitwell <keithw@vmware.com>
  31   *   Brian Paul
  32   */
  33
  34
  35 #include "st_context.h"
  36 #include "st_atom.h"
  37
  38 #include "pipe/p_context.h"
  39 #include "pipe/p_defines.h"
  40 #include "cso_cache/cso_context.h"
  41
  42 #include "framebuffer.h"
  43 #include "main/blend.h"
  44 #include "main/macros.h"
  45
  46 /**
  47  * Convert GLenum blend tokens to pipe tokens.
  48  * Both blend factors and blend funcs are accepted.
  49  */
  50 static GLuint
  51 translate_blend(GLenum blend)
  52 {
  53    switch (blend) {
  54    /* blend functions */
  55    case GL_FUNC_ADD:
  56       return PIPE_BLEND_ADD;
  57    case GL_FUNC_SUBTRACT:
  58       return PIPE_BLEND_SUBTRACT;
  59    case GL_FUNC_REVERSE_SUBTRACT:
  60       return PIPE_BLEND_REVERSE_SUBTRACT;
  61    case GL_MIN:
  62       return PIPE_BLEND_MIN;
  63    case GL_MAX:
  64       return PIPE_BLEND_MAX;
  65
  66    /* blend factors */
  67    case GL_ONE:
  68       return PIPE_BLENDFACTOR_ONE;
  69    case GL_SRC_COLOR:
  70       return PIPE_BLENDFACTOR_SRC_COLOR;
  71    case GL_SRC_ALPHA:
  72       return PIPE_BLENDFACTOR_SRC_ALPHA;
  73    case GL_DST_ALPHA:
  74       return PIPE_BLENDFACTOR_DST_ALPHA;
  75    case GL_DST_COLOR:
  76       return PIPE_BLENDFACTOR_DST_COLOR;
  77    case GL_SRC_ALPHA_SATURATE:
  78       return PIPE_BLENDFACTOR_SRC_ALPHA_SATURATE;
  79    case GL_CONSTANT_COLOR:
  80       return PIPE_BLENDFACTOR_CONST_COLOR;
  81    case GL_CONSTANT_ALPHA:
  82       return PIPE_BLENDFACTOR_CONST_ALPHA;
  83    case GL_SRC1_COLOR:
  84       return PIPE_BLENDFACTOR_SRC1_COLOR;
  85    case GL_SRC1_ALPHA:
  86       return PIPE_BLENDFACTOR_SRC1_ALPHA;
  87    case GL_ZERO:
  88       return PIPE_BLENDFACTOR_ZERO;
  89    case GL_ONE_MINUS_SRC_COLOR:
  90       return PIPE_BLENDFACTOR_INV_SRC_COLOR;
  91    case GL_ONE_MINUS_SRC_ALPHA:
  92       return PIPE_BLENDFACTOR_INV_SRC_ALPHA;
  93    case GL_ONE_MINUS_DST_COLOR:
  94       return PIPE_BLENDFACTOR_INV_DST_COLOR;
  95    case GL_ONE_MINUS_DST_ALPHA:
  96       return PIPE_BLENDFACTOR_INV_DST_ALPHA;
  97    case GL_ONE_MINUS_CONSTANT_COLOR:
  98       return PIPE_BLENDFACTOR_INV_CONST_COLOR;
  99    case GL_ONE_MINUS_CONSTANT_ALPHA:
 100       return PIPE_BLENDFACTOR_INV_CONST_ALPHA;
 101    case GL_ONE_MINUS_SRC1_COLOR:
 102       return PIPE_BLENDFACTOR_INV_SRC1_COLOR;
 103    case GL_ONE_MINUS_SRC1_ALPHA:
 104       return PIPE_BLENDFACTOR_INV_SRC1_ALPHA;
 105    default:
 106       assert("invalid GL token in translate_blend()" == NULL);
 107       return 0;
 108    }
 109 }
 110
 111 /**
 112  * Figure out if colormasks are different per rt.
 113  */
 114 static GLboolean
 115 colormask_per_rt(const struct gl_context *ctx, unsigned num_cb)
 116 {
 117    GLbitfield full_mask = _mesa_replicate_colormask(0xf, num_cb);
 118    GLbitfield repl_mask0 =
 119       _mesa_replicate_colormask(GET_COLORMASK(ctx->Color.ColorMask, 0),
 120                                 num_cb);
 121
 122    return (ctx->Color.ColorMask & full_mask) != repl_mask0;
 123 }
 124
 125 /**
 126  * Figure out if blend enables/state are different per rt.
 127  */
 128 static GLboolean
 129 blend_per_rt(const struct gl_context *ctx, unsigned num_cb)
 130 {
 131    GLbitfield cb_mask = u_bit_consecutive(0, num_cb);
 132    GLbitfield blend_enabled = ctx->Color.BlendEnabled & cb_mask;
 133
 134    if (blend_enabled && blend_enabled != cb_mask) {
 135       /* This can only happen if GL_EXT_draw_buffers2 is enabled */
 136       return GL_TRUE;
 137    }
 138    if (ctx->Color._BlendFuncPerBuffer || ctx->Color._BlendEquationPerBuffer) {
 139       /* this can only happen if GL_ARB_draw_buffers_blend is enabled */
 140       return GL_TRUE;
 141    }
 142    return GL_FALSE;
 143 }
 144
 145 void
 146 st_update_blend( struct st_context *st )
 147 {
 148    struct pipe_blend_state *blend = &st->state.blend;
 149    const struct gl_context *ctx = st->ctx;
 150    unsigned num_cb = st->state.fb_num_cb;
 151    unsigned num_state = 1;
 152    unsigned i, j;
 153
 154    memset(blend, 0, sizeof(*blend));
 155
 156    if (num_cb > 1 &&
 157        (blend_per_rt(ctx, num_cb) || colormask_per_rt(ctx, num_cb))) {
 158       num_state = num_cb;
 159       blend->independent_blend_enable = 1;
 160    }
 161
 162    for (i = 0; i < num_state; i++)
 163       blend->rt[i].colormask = GET_COLORMASK(ctx->Color.ColorMask, i);
 164
 165    if (ctx->Color.ColorLogicOpEnabled) {
 166       /* logicop enabled */
 167       blend->logicop_enable = 1;
 168       blend->logicop_func = ctx->Color._LogicOp;
 169    }
 170    else if (ctx->Color.BlendEnabled && !ctx->Color._AdvancedBlendMode) {
 171       /* blending enabled */
 172       for (i = 0, j = 0; i < num_state; i++) {
 173          if (!(ctx->Color.BlendEnabled & (1 << i)) ||
 174              (ctx->DrawBuffer->_IntegerBuffers & (1 << i)) ||
 175              !blend->rt[i].colormask)
 176             continue;
 177
 178          if (ctx->Extensions.ARB_draw_buffers_blend)
 179             j = i;
 180
 181          blend->rt[i].blend_enable = 1;
 182          blend->rt[i].rgb_func =
 183             translate_blend(ctx->Color.Blend[j].EquationRGB);
 184
 185          if (ctx->Color.Blend[i].EquationRGB == GL_MIN ||
 186              ctx->Color.Blend[i].EquationRGB == GL_MAX) {
 187             /* Min/max are special */
 188             blend->rt[i].rgb_src_factor = PIPE_BLENDFACTOR_ONE;
 189             blend->rt[i].rgb_dst_factor = PIPE_BLENDFACTOR_ONE;
 190          }
 191          else {
 192             blend->rt[i].rgb_src_factor =
 193                translate_blend(ctx->Color.Blend[j].SrcRGB);
 194             blend->rt[i].rgb_dst_factor =
 195                translate_blend(ctx->Color.Blend[j].DstRGB);
 196          }
 197
 198          blend->rt[i].alpha_func =
 199             translate_blend(ctx->Color.Blend[j].EquationA);
 200
 201          if (ctx->Color.Blend[i].EquationA == GL_MIN ||
 202              ctx->Color.Blend[i].EquationA == GL_MAX) {
 203             /* Min/max are special */
 204             blend->rt[i].alpha_src_factor = PIPE_BLENDFACTOR_ONE;
 205             blend->rt[i].alpha_dst_factor = PIPE_BLENDFACTOR_ONE;
 206          }
 207          else {
 208             blend->rt[i].alpha_src_factor =
 209                translate_blend(ctx->Color.Blend[j].SrcA);
 210             blend->rt[i].alpha_dst_factor =
 211                translate_blend(ctx->Color.Blend[j].DstA);
 212          }
 213       }
 214    }
 215    else {
 216       /* no blending / logicop */
 217    }
 218
 219    blend->dither = ctx->Color.DitherFlag;
 220
 221    if (_mesa_is_multisample_enabled(ctx) &&
 222        !(ctx->DrawBuffer->_IntegerBuffers & 0x1)) {
 223       /* Unlike in gallium/d3d10 these operations are only performed
 224        * if both msaa is enabled and we have a multisample buffer.
 225        */
 226       blend->alpha_to_coverage = ctx->Multisample.SampleAlphaToCoverage;
 227       blend->alpha_to_one = ctx->Multisample.SampleAlphaToOne;
 228    }
 229
 230    cso_set_blend(st->cso_context, blend);
 231 }
 232
 233 void
 234 st_update_blend_color(struct st_context *st)
 235 {
 236    struct pipe_blend_color bc;
 237
 238    COPY_4FV(bc.color, st->ctx->Color.BlendColorUnclamped);
 239    cso_set_blend_color(st->cso_context, &bc);
 240 }