/**************************************************************************
*
* Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
* 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 TUNGSTEN GRAPHICS 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.
*
**************************************************************************/
/**
* AA point stage: AA points are converted to quads and rendered with a
* special fragment shader. Another approach would be to use a texture
* map image of a point, but experiments indicate the quality isn't nearly
* as good as this approach.
*
* Note: this looks a lot like draw_aaline.c but there's actually little
* if any code that can be shared.
*
* Authors: Brian Paul
*/
#include "pipe/p_context.h"
#include "pipe/p_defines.h"
#include "pipe/p_shader_tokens.h"
#include "tgsi/tgsi_transform.h"
#include "tgsi/tgsi_dump.h"
#include "util/u_math.h"
#include "util/u_memory.h"
#include "draw_context.h"
#include "draw_vs.h"
#include "draw_pipe.h"
/** Approx number of new tokens for instructions in aa_transform_inst() */
#define NUM_NEW_TOKENS 200
/*
* Enabling NORMALIZE might give _slightly_ better results.
* Basically, it controls whether we compute distance as d=sqrt(x*x+y*y) or
* d=x*x+y*y. Since we're working with a unit circle, the later seems
* close enough and saves some costly instructions.
*/
#define NORMALIZE 0
/**
* Subclass of pipe_shader_state to carry extra fragment shader info.
*/
struct aapoint_fragment_shader
{
struct pipe_shader_state state;
void *driver_fs; /**< the regular shader */
void *aapoint_fs; /**< the aa point-augmented shader */
int generic_attrib; /**< The generic input attrib/texcoord we'll use */
};
/**
* Subclass of draw_stage
*/
struct aapoint_stage
{
struct draw_stage stage;
/** half of pipe_rasterizer_state::point_size */
float radius;
/** vertex attrib slot containing point size */
int psize_slot;
/** this is the vertex attrib slot for the new texcoords */
uint tex_slot;
/** vertex attrib slot containing position */
uint pos_slot;
/** Currently bound fragment shader */
struct aapoint_fragment_shader *fs;
/*
* Driver interface/override functions
*/
void * (*driver_create_fs_state)(struct pipe_context *,
const struct pipe_shader_state *);
void (*driver_bind_fs_state)(struct pipe_context *, void *);
void (*driver_delete_fs_state)(struct pipe_context *, void *);
};
/**
* Subclass of tgsi_transform_context, used for transforming the
* user's fragment shader to add the special AA instructions.
*/
struct aa_transform_context {
struct tgsi_transform_context base;
uint tempsUsed; /**< bitmask */
int colorOutput; /**< which output is the primary color */
int maxInput, maxGeneric; /**< max input index found */
int tmp0, colorTemp; /**< temp registers */
boolean firstInstruction;
};
/**
* TGSI declaration transform callback.
* Look for two free temp regs and available input reg for new texcoords.
*/
static void
aa_transform_decl(struct tgsi_transform_context *ctx,
struct tgsi_full_declaration *decl)
{
struct aa_transform_context *aactx = (struct aa_transform_context *) ctx;
if (decl->Declaration.File == TGSI_FILE_OUTPUT &&
decl->Semantic.Name == TGSI_SEMANTIC_COLOR &&
decl->Semantic.Index == 0) {
aactx->colorOutput = decl->Range.First;
}
else if (decl->Declaration.File == TGSI_FILE_INPUT) {
if ((int) decl->Range.Last > aactx->maxInput)
aactx->maxInput = decl->Range.Last;
if (decl->Semantic.Name == TGSI_SEMANTIC_GENERIC &&
(int) decl->Semantic.Index > aactx->maxGeneric) {
aactx->maxGeneric = decl->Semantic.Index;
}
}
else if (decl->Declaration.File == TGSI_FILE_TEMPORARY) {
uint i;
for (i = decl->Range.First;
i <= decl->Range.Last; i++) {
aactx->tempsUsed |= (1 << i);
}
}
ctx->emit_declaration(ctx, decl);
}
/**
* TGSI instruction transform callback.
* Replace writes to result.color w/ a temp reg.
* Upon END instruction, insert texture sampling code for antialiasing.
*/
static void
aa_transform_inst(struct tgsi_transform_context *ctx,
struct tgsi_full_instruction *inst)
{
struct aa_transform_context *aactx = (struct aa_transform_context *) ctx;
struct tgsi_full_instruction newInst;
if (aactx->firstInstruction) {
/* emit our new declarations before the first instruction */
struct tgsi_full_declaration decl;
const int texInput = aactx->maxInput + 1;
int tmp0;
uint i;
/* find two free temp regs */
for (i = 0; i < 32; i++) {
if ((aactx->tempsUsed & (1 << i)) == 0) {
/* found a free temp */
if (aactx->tmp0 < 0)
aactx->tmp0 = i;
else if (aactx->colorTemp < 0)
aactx->colorTemp = i;
else
break;
}
}
assert(aactx->colorTemp != aactx->tmp0);
tmp0 = aactx->tmp0;
/* declare new generic input/texcoord */
decl = tgsi_default_full_declaration();
decl.Declaration.File = TGSI_FILE_INPUT;
/* XXX this could be linear... */
decl.Declaration.Interpolate = 1;
decl.Declaration.Semantic = 1;
decl.Semantic.Name = TGSI_SEMANTIC_GENERIC;
decl.Semantic.Index = aactx->maxGeneric + 1;
decl.Range.First =
decl.Range.Last = texInput;
decl.Interp.Interpolate = TGSI_INTERPOLATE_PERSPECTIVE;
ctx->emit_declaration(ctx, &decl);
/* declare new temp regs */
decl = tgsi_default_full_declaration();
decl.Declaration.File = TGSI_FILE_TEMPORARY;
decl.Range.First =
decl.Range.Last = tmp0;
ctx->emit_declaration(ctx, &decl);
decl = tgsi_default_full_declaration();
decl.Declaration.File = TGSI_FILE_TEMPORARY;
decl.Range.First =
decl.Range.Last = aactx->colorTemp;
ctx->emit_declaration(ctx, &decl);
aactx->firstInstruction = FALSE;
/*
* Emit code to compute fragment coverage, kill if outside point radius
*
* Temp reg0 usage:
* t0.x = distance of fragment from center point
* t0.y = boolean, is t0.x > 1.0, also misc temp usage
* t0.z = temporary for computing 1/(1-k) value
* t0.w = final coverage value
*/
/* MUL t0.xy, tex, tex; # compute x^2, y^2 */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_MUL;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Dst[0].Register.Index = tmp0;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_XY;
newInst.Instruction.NumSrcRegs = 2;
newInst.Src[0].Register.File = TGSI_FILE_INPUT;
newInst.Src[0].Register.Index = texInput;
newInst.Src[1].Register.File = TGSI_FILE_INPUT;
newInst.Src[1].Register.Index = texInput;
ctx->emit_instruction(ctx, &newInst);
/* ADD t0.x, t0.x, t0.y; # x^2 + y^2 */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_ADD;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Dst[0].Register.Index = tmp0;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_X;
newInst.Instruction.NumSrcRegs = 2;
newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[0].Register.Index = tmp0;
newInst.Src[0].Register.SwizzleX = TGSI_SWIZZLE_X;
newInst.Src[1].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[1].Register.Index = tmp0;
newInst.Src[1].Register.SwizzleX = TGSI_SWIZZLE_Y;
ctx->emit_instruction(ctx, &newInst);
#if NORMALIZE /* OPTIONAL normalization of length */
/* RSQ t0.x, t0.x; */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_RSQ;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Dst[0].Register.Index = tmp0;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_X;
newInst.Instruction.NumSrcRegs = 1;
newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[0].Register.Index = tmp0;
ctx->emit_instruction(ctx, &newInst);
/* RCP t0.x, t0.x; */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_RCP;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Dst[0].Register.Index = tmp0;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_X;
newInst.Instruction.NumSrcRegs = 1;
newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[0].Register.Index = tmp0;
ctx->emit_instruction(ctx, &newInst);
#endif
/* SGT t0.y, t0.xxxx, tex.wwww; # bool b = d > 1 (NOTE tex.w == 1) */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_SGT;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Dst[0].Register.Index = tmp0;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_Y;
newInst.Instruction.NumSrcRegs = 2;
newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[0].Register.Index = tmp0;
newInst.Src[0].Register.SwizzleY = TGSI_SWIZZLE_X;
newInst.Src[1].Register.File = TGSI_FILE_INPUT;
newInst.Src[1].Register.Index = texInput;
newInst.Src[1].Register.SwizzleY = TGSI_SWIZZLE_W;
ctx->emit_instruction(ctx, &newInst);
/* KIL -tmp0.yyyy; # if -tmp0.y < 0, KILL */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_KIL;
newInst.Instruction.NumDstRegs = 0;
newInst.Instruction.NumSrcRegs = 1;
newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[0].Register.Index = tmp0;
newInst.Src[0].Register.SwizzleX = TGSI_SWIZZLE_Y;
newInst.Src[0].Register.SwizzleY = TGSI_SWIZZLE_Y;
newInst.Src[0].Register.SwizzleZ = TGSI_SWIZZLE_Y;
newInst.Src[0].Register.SwizzleW = TGSI_SWIZZLE_Y;
newInst.Src[0].Register.Negate = 1;
ctx->emit_instruction(ctx, &newInst);
/* compute coverage factor = (1-d)/(1-k) */
/* SUB t0.z, tex.w, tex.z; # m = 1 - k */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_SUB;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Dst[0].Register.Index = tmp0;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_Z;
newInst.Instruction.NumSrcRegs = 2;
newInst.Src[0].Register.File = TGSI_FILE_INPUT;
newInst.Src[0].Register.Index = texInput;
newInst.Src[0].Register.SwizzleZ = TGSI_SWIZZLE_W;
newInst.Src[1].Register.File = TGSI_FILE_INPUT;
newInst.Src[1].Register.Index = texInput;
newInst.Src[1].Register.SwizzleZ = TGSI_SWIZZLE_Z;
ctx->emit_instruction(ctx, &newInst);
/* RCP t0.z, t0.z; # t0.z = 1 / m */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_RCP;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Dst[0].Register.Index = tmp0;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_Z;
newInst.Instruction.NumSrcRegs = 1;
newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[0].Register.Index = tmp0;
newInst.Src[0].Register.SwizzleX = TGSI_SWIZZLE_Z;
ctx->emit_instruction(ctx, &newInst);
/* SUB t0.y, 1, t0.x; # d = 1 - d */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_SUB;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Dst[0].Register.Index = tmp0;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_Y;
newInst.Instruction.NumSrcRegs = 2;
newInst.Src[0].Register.File = TGSI_FILE_INPUT;
newInst.Src[0].Register.Index = texInput;
newInst.Src[0].Register.SwizzleY = TGSI_SWIZZLE_W;
newInst.Src[1].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[1].Register.Index = tmp0;
newInst.Src[1].Register.SwizzleY = TGSI_SWIZZLE_X;
ctx->emit_instruction(ctx, &newInst);
/* MUL t0.w, t0.y, t0.z; # coverage = d * m */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_MUL;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Dst[0].Register.Index = tmp0;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_W;
newInst.Instruction.NumSrcRegs = 2;
newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[0].Register.Index = tmp0;
newInst.Src[0].Register.SwizzleW = TGSI_SWIZZLE_Y;
newInst.Src[1].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[1].Register.Index = tmp0;
newInst.Src[1].Register.SwizzleW = TGSI_SWIZZLE_Z;
ctx->emit_instruction(ctx, &newInst);
/* SLE t0.y, t0.x, tex.z; # bool b = distance <= k */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_SLE;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Dst[0].Register.Index = tmp0;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_Y;
newInst.Instruction.NumSrcRegs = 2;
newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[0].Register.Index = tmp0;
newInst.Src[0].Register.SwizzleY = TGSI_SWIZZLE_X;
newInst.Src[1].Register.File = TGSI_FILE_INPUT;
newInst.Src[1].Register.Index = texInput;
newInst.Src[1].Register.SwizzleY = TGSI_SWIZZLE_Z;
ctx->emit_instruction(ctx, &newInst);
/* CMP t0.w, -t0.y, tex.w, t0.w;
* # if -t0.y < 0 then
* t0.w = 1
* else
* t0.w = t0.w
*/
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_CMP;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Dst[0].Register.Index = tmp0;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_W;
newInst.Instruction.NumSrcRegs = 3;
newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[0].Register.Index = tmp0;
newInst.Src[0].Register.SwizzleX = TGSI_SWIZZLE_Y;
newInst.Src[0].Register.SwizzleY = TGSI_SWIZZLE_Y;
newInst.Src[0].Register.SwizzleZ = TGSI_SWIZZLE_Y;
newInst.Src[0].Register.SwizzleW = TGSI_SWIZZLE_Y;
newInst.Src[0].Register.Negate = 1;
newInst.Src[1].Register.File = TGSI_FILE_INPUT;
newInst.Src[1].Register.Index = texInput;
newInst.Src[1].Register.SwizzleX = TGSI_SWIZZLE_W;
newInst.Src[1].Register.SwizzleY = TGSI_SWIZZLE_W;
newInst.Src[1].Register.SwizzleZ = TGSI_SWIZZLE_W;
newInst.Src[1].Register.SwizzleW = TGSI_SWIZZLE_W;
newInst.Src[2].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[2].Register.Index = tmp0;
newInst.Src[2].Register.SwizzleX = TGSI_SWIZZLE_W;
newInst.Src[2].Register.SwizzleY = TGSI_SWIZZLE_W;
newInst.Src[2].Register.SwizzleZ = TGSI_SWIZZLE_W;
newInst.Src[2].Register.SwizzleW = TGSI_SWIZZLE_W;
ctx->emit_instruction(ctx, &newInst);
}
if (inst->Instruction.Opcode == TGSI_OPCODE_END) {
/* add alpha modulation code at tail of program */
/* MOV result.color.xyz, colorTemp; */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_MOV;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_OUTPUT;
newInst.Dst[0].Register.Index = aactx->colorOutput;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_XYZ;
newInst.Instruction.NumSrcRegs = 1;
newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[0].Register.Index = aactx->colorTemp;
ctx->emit_instruction(ctx, &newInst);
/* MUL result.color.w, colorTemp, tmp0.w; */
newInst = tgsi_default_full_instruction();
newInst.Instruction.Opcode = TGSI_OPCODE_MUL;
newInst.Instruction.NumDstRegs = 1;
newInst.Dst[0].Register.File = TGSI_FILE_OUTPUT;
newInst.Dst[0].Register.Index = aactx->colorOutput;
newInst.Dst[0].Register.WriteMask = TGSI_WRITEMASK_W;
newInst.Instruction.NumSrcRegs = 2;
newInst.Src[0].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[0].Register.Index = aactx->colorTemp;
newInst.Src[1].Register.File = TGSI_FILE_TEMPORARY;
newInst.Src[1].Register.Index = aactx->tmp0;
ctx->emit_instruction(ctx, &newInst);
}
else {
/* Not an END instruction.
* Look for writes to result.color and replace with colorTemp reg.
*/
uint i;
for (i = 0; i < inst->Instruction.NumDstRegs; i++) {
struct tgsi_full_dst_register *dst = &inst->Dst[i];
if (dst->Register.File == TGSI_FILE_OUTPUT &&
dst->Register.Index == aactx->colorOutput) {
dst->Register.File = TGSI_FILE_TEMPORARY;
dst->Register.Index = aactx->colorTemp;
}
}
}
ctx->emit_instruction(ctx, inst);
}
/**
* Generate the frag shader we'll use for drawing AA points.
* This will be the user's shader plus some texture/modulate instructions.
*/
static boolean
generate_aapoint_fs(struct aapoint_stage *aapoint)
{
const struct pipe_shader_state *orig_fs = &aapoint->fs->state;
struct pipe_shader_state aapoint_fs;
struct aa_transform_context transform;
const uint newLen = tgsi_num_tokens(orig_fs->tokens) + NUM_NEW_TOKENS;
struct pipe_context *pipe = aapoint->stage.draw->pipe;
aapoint_fs = *orig_fs; /* copy to init */
aapoint_fs.tokens = tgsi_alloc_tokens(newLen);
if (aapoint_fs.tokens == NULL)
return FALSE;
memset(&transform, 0, sizeof(transform));
transform.colorOutput = -1;
transform.maxInput = -1;
transform.maxGeneric = -1;
transform.colorTemp = -1;
transform.tmp0 = -1;
transform.firstInstruction = TRUE;
transform.base.transform_instruction = aa_transform_inst;
transform.base.transform_declaration = aa_transform_decl;
tgsi_transform_shader(orig_fs->tokens,
(struct tgsi_token *) aapoint_fs.tokens,
newLen, &transform.base);
#if 0 /* DEBUG */
debug_printf("draw_aapoint, orig shader:\n");
tgsi_dump(orig_fs->tokens, 0);
debug_printf("draw_aapoint, new shader:\n");
tgsi_dump(aapoint_fs.tokens, 0);
#endif
aapoint->fs->aapoint_fs
= aapoint->driver_create_fs_state(pipe, &aapoint_fs);
if (aapoint->fs->aapoint_fs == NULL)
goto fail;
aapoint->fs->generic_attrib = transform.maxGeneric + 1;
FREE((void *)aapoint_fs.tokens);
return TRUE;
fail:
FREE((void *)aapoint_fs.tokens);
return FALSE;
}
/**
* When we're about to draw our first AA point in a batch, this function is
* called to tell the driver to bind our modified fragment shader.
*/
static boolean
bind_aapoint_fragment_shader(struct aapoint_stage *aapoint)
{
struct draw_context *draw = aapoint->stage.draw;
struct pipe_context *pipe = draw->pipe;
if (!aapoint->fs->aapoint_fs &&
!generate_aapoint_fs(aapoint))
return FALSE;
draw->suspend_flushing = TRUE;
aapoint->driver_bind_fs_state(pipe, aapoint->fs->aapoint_fs);
draw->suspend_flushing = FALSE;
return TRUE;
}
static INLINE struct aapoint_stage *
aapoint_stage( struct draw_stage *stage )
{
return (struct aapoint_stage *) stage;
}
/**
* Draw an AA point by drawing a quad.
*/
static void
aapoint_point(struct draw_stage *stage, struct prim_header *header)
{
const struct aapoint_stage *aapoint = aapoint_stage(stage);
struct prim_header tri;
struct vertex_header *v[4];
const uint tex_slot = aapoint->tex_slot;
const uint pos_slot = aapoint->pos_slot;
float radius, *pos, *tex;
uint i;
float k;
if (aapoint->psize_slot >= 0) {
radius = 0.5f * header->v[0]->data[aapoint->psize_slot][0];
}
else {
radius = aapoint->radius;
}
/*
* Note: the texcoords (generic attrib, really) we use are special:
* The S and T components simply vary from -1 to +1.
* The R component is k, below.
* The Q component is 1.0 and will used as a handy constant in the
* fragment shader.
*/
/*
* k is the threshold distance from the point's center at which
* we begin alpha attenuation (the coverage value).
* Operating within a unit circle, we'll compute the fragment's
* distance 'd' from the center point using the texcoords.
* IF d > 1.0 THEN
* KILL fragment
* ELSE IF d > k THEN
* compute coverage in [0,1] proportional to d in [k, 1].
* ELSE
* coverage = 1.0; // full coverage
* ENDIF
*
* Note: the ELSEIF and ELSE clauses are actually implemented with CMP to
* avoid using IF/ELSE/ENDIF TGSI opcodes.
*/
#if !NORMALIZE
k = 1.0f / radius;
k = 1.0f - 2.0f * k + k * k;
#else
k = 1.0f - 1.0f / radius;
#endif
/* allocate/dup new verts */
for (i = 0; i < 4; i++) {
v[i] = dup_vert(stage, header->v[0], i);
}
/* new verts */
pos = v[0]->data[pos_slot];
pos[0] -= radius;
pos[1] -= radius;
pos = v[1]->data[pos_slot];
pos[0] += radius;
pos[1] -= radius;
pos = v[2]->data[pos_slot];
pos[0] += radius;
pos[1] += radius;
pos = v[3]->data[pos_slot];
pos[0] -= radius;
pos[1] += radius;
/* new texcoords */
tex = v[0]->data[tex_slot];
ASSIGN_4V(tex, -1, -1, k, 1);
tex = v[1]->data[tex_slot];
ASSIGN_4V(tex, 1, -1, k, 1);
tex = v[2]->data[tex_slot];
ASSIGN_4V(tex, 1, 1, k, 1);
tex = v[3]->data[tex_slot];
ASSIGN_4V(tex, -1, 1, k, 1);
/* emit 2 tris for the quad strip */
tri.v[0] = v[0];
tri.v[1] = v[1];
tri.v[2] = v[2];
stage->next->tri( stage->next, &tri );
tri.v[0] = v[0];
tri.v[1] = v[2];
tri.v[2] = v[3];
stage->next->tri( stage->next, &tri );
}
static void
aapoint_first_point(struct draw_stage *stage, struct prim_header *header)
{
auto struct aapoint_stage *aapoint = aapoint_stage(stage);
struct draw_context *draw = stage->draw;
struct pipe_context *pipe = draw->pipe;
const struct pipe_rasterizer_state *rast = draw->rasterizer;
void *r;
assert(draw->rasterizer->point_smooth);
if (draw->rasterizer->point_size <= 2.0)
aapoint->radius = 1.0;
else
aapoint->radius = 0.5f * draw->rasterizer->point_size;
/*
* Bind (generate) our fragprog.
*/
bind_aapoint_fragment_shader(aapoint);
/* update vertex attrib info */
aapoint->pos_slot = draw_current_shader_position_output(draw);
/* allocate the extra post-transformed vertex attribute */
aapoint->tex_slot = draw_alloc_extra_vertex_attrib(draw,
TGSI_SEMANTIC_GENERIC,
aapoint->fs->generic_attrib);
assert(aapoint->tex_slot > 0); /* output[0] is vertex pos */
/* find psize slot in post-transform vertex */
aapoint->psize_slot = -1;
if (draw->rasterizer->point_size_per_vertex) {
const struct tgsi_shader_info *info = draw_get_shader_info(draw);
uint i;
/* find PSIZ vertex output */
for (i = 0; i < info->num_outputs; i++) {
if (info->output_semantic_name[i] == TGSI_SEMANTIC_PSIZE) {
aapoint->psize_slot = i;
break;
}
}
}
draw->suspend_flushing = TRUE;
/* Disable triangle culling, stippling, unfilled mode etc. */
r = draw_get_rasterizer_no_cull(draw, rast->scissor, rast->flatshade);
pipe->bind_rasterizer_state(pipe, r);
draw->suspend_flushing = FALSE;
/* now really draw first point */
stage->point = aapoint_point;
stage->point(stage, header);
}
static void
aapoint_flush(struct draw_stage *stage, unsigned flags)
{
struct draw_context *draw = stage->draw;
struct aapoint_stage *aapoint = aapoint_stage(stage);
struct pipe_context *pipe = draw->pipe;
stage->point = aapoint_first_point;
stage->next->flush( stage->next, flags );
/* restore original frag shader */
draw->suspend_flushing = TRUE;
aapoint->driver_bind_fs_state(pipe, aapoint->fs ? aapoint->fs->driver_fs : NULL);
/* restore original rasterizer state */
if (draw->rast_handle) {
pipe->bind_rasterizer_state(pipe, draw->rast_handle);
}
draw->suspend_flushing = FALSE;
draw_remove_extra_vertex_attribs(draw);
}
static void
aapoint_reset_stipple_counter(struct draw_stage *stage)
{
stage->next->reset_stipple_counter( stage->next );
}
static void
aapoint_destroy(struct draw_stage *stage)
{
struct aapoint_stage* aapoint = aapoint_stage(stage);
struct pipe_context *pipe = stage->draw->pipe;
draw_free_temp_verts( stage );
/* restore the old entry points */
pipe->create_fs_state = aapoint->driver_create_fs_state;
pipe->bind_fs_state = aapoint->driver_bind_fs_state;
pipe->delete_fs_state = aapoint->driver_delete_fs_state;
FREE( stage );
}
static struct aapoint_stage *
draw_aapoint_stage(struct draw_context *draw)
{
struct aapoint_stage *aapoint = CALLOC_STRUCT(aapoint_stage);
if (aapoint == NULL)
goto fail;
aapoint->stage.draw = draw;
aapoint->stage.name = "aapoint";
aapoint->stage.next = NULL;
aapoint->stage.point = aapoint_first_point;
aapoint->stage.line = draw_pipe_passthrough_line;
aapoint->stage.tri = draw_pipe_passthrough_tri;
aapoint->stage.flush = aapoint_flush;
aapoint->stage.reset_stipple_counter = aapoint_reset_stipple_counter;
aapoint->stage.destroy = aapoint_destroy;
if (!draw_alloc_temp_verts( &aapoint->stage, 4 ))
goto fail;
return aapoint;
fail:
if (aapoint)
aapoint->stage.destroy(&aapoint->stage);
return NULL;
}
static struct aapoint_stage *
aapoint_stage_from_pipe(struct pipe_context *pipe)
{
struct draw_context *draw = (struct draw_context *) pipe->draw;
return aapoint_stage(draw->pipeline.aapoint);
}
/**
* This function overrides the driver's create_fs_state() function and
* will typically be called by the state tracker.
*/
static void *
aapoint_create_fs_state(struct pipe_context *pipe,
const struct pipe_shader_state *fs)
{
struct aapoint_stage *aapoint = aapoint_stage_from_pipe(pipe);
struct aapoint_fragment_shader *aafs = CALLOC_STRUCT(aapoint_fragment_shader);
if (aafs == NULL)
return NULL;
aafs->state.tokens = tgsi_dup_tokens(fs->tokens);
/* pass-through */
aafs->driver_fs = aapoint->driver_create_fs_state(pipe, fs);
return aafs;
}
static void
aapoint_bind_fs_state(struct pipe_context *pipe, void *fs)
{
struct aapoint_stage *aapoint = aapoint_stage_from_pipe(pipe);
struct aapoint_fragment_shader *aafs = (struct aapoint_fragment_shader *) fs;
/* save current */
aapoint->fs = aafs;
/* pass-through */
aapoint->driver_bind_fs_state(pipe,
(aafs ? aafs->driver_fs : NULL));
}
static void
aapoint_delete_fs_state(struct pipe_context *pipe, void *fs)
{
struct aapoint_stage *aapoint = aapoint_stage_from_pipe(pipe);
struct aapoint_fragment_shader *aafs = (struct aapoint_fragment_shader *) fs;
/* pass-through */
aapoint->driver_delete_fs_state(pipe, aafs->driver_fs);
if (aafs->aapoint_fs)
aapoint->driver_delete_fs_state(pipe, aafs->aapoint_fs);
FREE((void*)aafs->state.tokens);
FREE(aafs);
}
/**
* Called by drivers that want to install this AA point prim stage
* into the draw module's pipeline. This will not be used if the
* hardware has native support for AA points.
*/
boolean
draw_install_aapoint_stage(struct draw_context *draw,
struct pipe_context *pipe)
{
struct aapoint_stage *aapoint;
pipe->draw = (void *) draw;
/*
* Create / install AA point drawing / prim stage
*/
aapoint = draw_aapoint_stage( draw );
if (aapoint == NULL)
return FALSE;
/* save original driver functions */
aapoint->driver_create_fs_state = pipe->create_fs_state;
aapoint->driver_bind_fs_state = pipe->bind_fs_state;
aapoint->driver_delete_fs_state = pipe->delete_fs_state;
/* override the driver's functions */
pipe->create_fs_state = aapoint_create_fs_state;
pipe->bind_fs_state = aapoint_bind_fs_state;
pipe->delete_fs_state = aapoint_delete_fs_state;
draw->pipeline.aapoint = &aapoint->stage;
return TRUE;
}