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ppsspp/GPU/Common/SplineCommon.cpp

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// Copyright (c) 2013- PPSSPP Project.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0 or later versions.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License 2.0 for more details.
// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/
// Official git repository and contact information can be found at
// https://github.com/hrydgard/ppsspp and http://www.ppsspp.org/.
#include <string.h>
#include <algorithm>
#include "profiler/profiler.h"
#include "Common/CPUDetect.h"
#include "Common/MemoryUtil.h"
#include "Core/Config.h"
#include "GPU/Common/SplineCommon.h"
#include "GPU/Common/DrawEngineCommon.h"
#include "GPU/ge_constants.h"
#include "GPU/GPUState.h" // only needed for UVScale stuff
#if defined(_M_SSE)
#include <emmintrin.h>
inline __m128 SSECrossProduct(__m128 a, __m128 b)
{
const __m128 left = _mm_mul_ps(_mm_shuffle_ps(a, a, _MM_SHUFFLE(3, 0, 2, 1)), _mm_shuffle_ps(b, b, _MM_SHUFFLE(3, 1, 0, 2)));
const __m128 right = _mm_mul_ps(_mm_shuffle_ps(a, a, _MM_SHUFFLE(3, 1, 0, 2)), _mm_shuffle_ps(b, b, _MM_SHUFFLE(3, 0, 2, 1)));
return _mm_sub_ps(left, right);
}
inline __m128 SSENormalizeMultiplierSSE2(__m128 v)
{
const __m128 sq = _mm_mul_ps(v, v);
const __m128 r2 = _mm_shuffle_ps(sq, sq, _MM_SHUFFLE(0, 0, 0, 1));
const __m128 r3 = _mm_shuffle_ps(sq, sq, _MM_SHUFFLE(0, 0, 0, 2));
const __m128 res = _mm_add_ss(r3, _mm_add_ss(r2, sq));
const __m128 rt = _mm_rsqrt_ss(res);
return _mm_shuffle_ps(rt, rt, _MM_SHUFFLE(0, 0, 0, 0));
}
#if _M_SSE >= 0x401
#include <smmintrin.h>
inline __m128 SSENormalizeMultiplierSSE4(__m128 v)
{
return _mm_rsqrt_ps(_mm_dp_ps(v, v, 0xFF));
}
inline __m128 SSENormalizeMultiplier(bool useSSE4, __m128 v)
{
if (useSSE4)
return SSENormalizeMultiplierSSE4(v);
return SSENormalizeMultiplierSSE2(v);
}
#else
inline __m128 SSENormalizeMultiplier(bool useSSE4, __m128 v)
{
return SSENormalizeMultiplierSSE2(v);
}
#endif
#endif
#define START_OPEN 1
#define END_OPEN 2
static void CopyQuad(u8 *&dest, const SimpleVertex *v1, const SimpleVertex *v2, const SimpleVertex* v3, const SimpleVertex *v4) {
int vertexSize = sizeof(SimpleVertex);
memcpy(dest, v1, vertexSize);
dest += vertexSize;
memcpy(dest, v2, vertexSize);
dest += vertexSize;
memcpy(dest, v3, vertexSize);
dest += vertexSize;
memcpy(dest, v4, vertexSize);
dest += vertexSize;
}
static void CopyQuadIndex(u16 *&indices, GEPatchPrimType type, const int idx0, const int idx1, const int idx2, const int idx3) {
if (type == GE_PATCHPRIM_LINES) {
*(indices++) = idx0;
*(indices++) = idx2;
*(indices++) = idx1;
*(indices++) = idx3;
*(indices++) = idx1;
*(indices++) = idx2;
}
else {
*(indices++) = idx0;
*(indices++) = idx2;
*(indices++) = idx1;
*(indices++) = idx1;
*(indices++) = idx2;
*(indices++) = idx3;
}
}
#undef b2
// Bernstein basis functions
inline float bern0(float x) { return (1 - x) * (1 - x) * (1 - x); }
inline float bern1(float x) { return 3 * x * (1 - x) * (1 - x); }
inline float bern2(float x) { return 3 * x * x * (1 - x); }
inline float bern3(float x) { return x * x * x; }
inline float bern0deriv(float x) { return -3 * (x - 1) * (x - 1); }
inline float bern1deriv(float x) { return 9 * x * x - 12 * x + 3; }
inline float bern2deriv(float x) { return 3 * (2 - 3 * x) * x; }
inline float bern3deriv(float x) { return 3 * x * x; }
// http://en.wikipedia.org/wiki/Bernstein_polynomial
static Math3D::Vec2f Bernstein3D(const Math3D::Vec2f& p0, const Math3D::Vec2f& p1, const Math3D::Vec2f& p2, const Math3D::Vec2f& p3, float x) {
if (x == 0) return p0;
else if (x == 1) return p3;
return p0 * bern0(x) + p1 * bern1(x) + p2 * bern2(x) + p3 * bern3(x);
}
static Vec3f Bernstein3D(const Vec3f& p0, const Vec3f& p1, const Vec3f& p2, const Vec3f& p3, float x) {
if (x == 0) return p0;
else if (x == 1) return p3;
return p0 * bern0(x) + p1 * bern1(x) + p2 * bern2(x) + p3 * bern3(x);
}
static Vec4f Bernstein3D(const Vec4f& p0, const Vec4f& p1, const Vec4f& p2, const Vec4f& p3, float x) {
if (x == 0) return p0;
else if (x == 1) return p3;
return p0 * bern0(x) + p1 * bern1(x) + p2 * bern2(x) + p3 * bern3(x);
}
static Vec4f Bernstein3D(const u32& p0, const u32& p1, const u32& p2, const u32& p3, float x) {
return Bernstein3D(Vec4f::FromRGBA(p0), Vec4f::FromRGBA(p1), Vec4f::FromRGBA(p2), Vec4f::FromRGBA(p3), x);
}
static Vec3f Bernstein3DDerivative(const Vec3f& p0, const Vec3f& p1, const Vec3f& p2, const Vec3f& p3, float x) {
return p0 * bern0deriv(x) + p1 * bern1deriv(x) + p2 * bern2deriv(x) + p3 * bern3deriv(x);
}
static void spline_n_4(int i, float t, float *knot, float *splineVal) {
knot += i + 1;
#ifdef _M_SSE
const __m128 knot012 = _mm_loadu_ps(&knot[0]);
const __m128 knot345 = _mm_loadu_ps(&knot[3]);
const __m128 t012 = _mm_sub_ps(_mm_set_ps1(t), knot012);
const __m128 f30_41_52 = _mm_div_ps(t012, _mm_sub_ps(knot345, knot012));
const __m128 knot343 = _mm_shuffle_ps(knot345, knot345, _MM_SHUFFLE(3, 0, 1, 0));
const __m128 knot122 = _mm_shuffle_ps(knot012, knot012, _MM_SHUFFLE(3, 2, 2, 1));
const __m128 t122 = _mm_shuffle_ps(t012, t012, _MM_SHUFFLE(3, 2, 2, 1));
const __m128 f31_42_32 = _mm_div_ps(t122, _mm_sub_ps(knot343, knot122));
// It's still faster to use SSE, even with this.
float MEMORY_ALIGNED16(ff30_41_52[4]);
float MEMORY_ALIGNED16(ff31_42_32[4]);
_mm_store_ps(ff30_41_52, f30_41_52);
_mm_store_ps(ff31_42_32, f31_42_32);
const float &f30 = ff30_41_52[0];
const float &f41 = ff30_41_52[1];
const float &f52 = ff30_41_52[2];
const float &f31 = ff31_42_32[0];
const float &f42 = ff31_42_32[1];
const float &f32 = ff31_42_32[2];
#else
// TODO: Maybe compilers could be coaxed into vectorizing this code without the above explicitly...
float t0 = (t - knot[0]);
float t1 = (t - knot[1]);
float t2 = (t - knot[2]);
// TODO: All our knots are integers so we should be able to get rid of these divisions (How?)
float f30 = t0/(knot[3]-knot[0]);
float f41 = t1/(knot[4]-knot[1]);
float f52 = t2/(knot[5]-knot[2]);
float f31 = t1/(knot[3]-knot[1]);
float f42 = t2/(knot[4]-knot[2]);
float f32 = t2/(knot[3]-knot[2]);
#endif
float a = (1-f30)*(1-f31);
float b = (f31*f41);
float c = (1-f41)*(1-f42);
float d = (f42*f52);
splineVal[0] = a-(a*f32);
splineVal[1] = 1-a-b+((a+b+c-1)*f32);
splineVal[2] = b+((1-b-c-d)*f32);
splineVal[3] = d*f32;
}
// knot should be an array sized n + 5 (n + 1 + 1 + degree (cubic))
static void spline_knot(int n, int type, float *knot) {
memset(knot, 0, sizeof(float) * (n + 5));
for (int i = 0; i < n - 1; ++i)
knot[i + 3] = (float)i;
if ((type & 1) == 0) {
knot[0] = -3;
knot[1] = -2;
knot[2] = -1;
}
if ((type & 2) == 0) {
knot[n + 2] = (float)(n - 1);
knot[n + 3] = (float)(n);
knot[n + 4] = (float)(n + 1);
} else {
knot[n + 2] = (float)(n - 2);
knot[n + 3] = (float)(n - 2);
knot[n + 4] = (float)(n - 2);
}
}
// Prepare mesh of one patch for "Instanced Tessellation".
static void TessellateSplinePatchHardware(u8 *&dest, u16 *indices, int &count, const SplinePatchLocal &spatch) {
SimpleVertex *&vertices = (SimpleVertex*&)dest;
float inv_u = 1.0f / (float)spatch.tess_u;
float inv_v = 1.0f / (float)spatch.tess_v;
// Generating simple input vertices for the spline-computing vertex shader.
for (int tile_v = 0; tile_v < spatch.tess_v + 1; ++tile_v) {
for (int tile_u = 0; tile_u < spatch.tess_u + 1; ++tile_u) {
SimpleVertex &vert = vertices[tile_v * (spatch.tess_u + 1) + tile_u];
vert.pos.x = (float)tile_u * inv_u;
vert.pos.y = (float)tile_v * inv_v;
// TODO: Move to shader uniform and unify this method spline and bezier if necessary.
// For compute normal
vert.nrm.x = inv_u;
vert.nrm.y = inv_v;
}
}
// Combine the vertices into triangles.
for (int tile_v = 0; tile_v < spatch.tess_v; ++tile_v) {
for (int tile_u = 0; tile_u < spatch.tess_u; ++tile_u) {
int idx0 = tile_v * (spatch.tess_u + 1) + tile_u;
int idx1 = tile_v * (spatch.tess_u + 1) + tile_u + 1;
int idx2 = (tile_v + 1) * (spatch.tess_u + 1) + tile_u;
int idx3 = (tile_v + 1) * (spatch.tess_u + 1) + tile_u + 1;
CopyQuadIndex(indices, spatch.primType, idx0, idx1, idx2, idx3);
count += 6;
}
}
}
static void _SplinePatchLowQuality(u8 *&dest, u16 *indices, int &count, const SplinePatchLocal &spatch, u32 origVertType) {
// Fast and easy way - just draw the control points, generate some very basic normal vector substitutes.
// Very inaccurate but okay for Loco Roco. Maybe should keep it as an option because it's fast.
const int tile_min_u = (spatch.type_u & START_OPEN) ? 0 : 1;
const int tile_min_v = (spatch.type_v & START_OPEN) ? 0 : 1;
const int tile_max_u = (spatch.type_u & END_OPEN) ? spatch.count_u - 1 : spatch.count_u - 2;
const int tile_max_v = (spatch.type_v & END_OPEN) ? spatch.count_v - 1 : spatch.count_v - 2;
float tu_width = (float)spatch.count_u - 3.0f;
float tv_height = (float)spatch.count_v - 3.0f;
tu_width /= (float)(tile_max_u - tile_min_u);
tv_height /= (float)(tile_max_v - tile_min_v);
GEPatchPrimType prim_type = spatch.primType;
bool computeNormals = spatch.computeNormals;
bool patchFacing = spatch.patchFacing;
int i = 0;
for (int tile_v = tile_min_v; tile_v < tile_max_v; ++tile_v) {
for (int tile_u = tile_min_u; tile_u < tile_max_u; ++tile_u) {
int point_index = tile_u + tile_v * spatch.count_u;
SimpleVertex v0 = *spatch.points[point_index];
SimpleVertex v1 = *spatch.points[point_index + 1];
SimpleVertex v2 = *spatch.points[point_index + spatch.count_u];
SimpleVertex v3 = *spatch.points[point_index + spatch.count_u + 1];
// Generate UV. TODO: Do this even if UV specified in control points?
if ((origVertType & GE_VTYPE_TC_MASK) == 0) {
float u = (tile_u - tile_min_u) * tu_width;
float v = (tile_v - tile_min_v) * tv_height;
v0.uv[0] = u;
v0.uv[1] = v;
v1.uv[0] = u + tu_width;
v1.uv[1] = v;
v2.uv[0] = u;
v2.uv[1] = v + tv_height;
v3.uv[0] = u + tu_width;
v3.uv[1] = v + tv_height;
}
// Generate normal if lighting is enabled (otherwise there's no point).
// This is a really poor quality algorithm, we get facet normals.
if (computeNormals) {
Vec3Packedf norm = Cross(v1.pos - v0.pos, v2.pos - v0.pos);
norm.Normalize();
if (patchFacing)
norm *= -1.0f;
v0.nrm = norm;
v1.nrm = norm;
v2.nrm = norm;
v3.nrm = norm;
}
int idx0 = i * 4 + 0;
int idx1 = i * 4 + 1;
int idx2 = i * 4 + 2;
int idx3 = i * 4 + 3;
i++;
CopyQuad(dest, &v0, &v1, &v2, &v3);
CopyQuadIndex(indices, prim_type, idx0, idx1, idx2, idx3);
count += 6;
}
}
}
static inline void AccumulateWeighted(Vec3f &out, const Vec3Packedf &in, const Vec4f &w) {
#ifdef _M_SSE
out.vec = _mm_add_ps(out.vec, _mm_mul_ps(_mm_loadu_ps(in.AsArray()), w.vec));
#else
out += in * w.x;
#endif
}
static inline void AccumulateWeighted(Vec4f &out, const Vec4f &in, const Vec4f &w) {
#ifdef _M_SSE
out.vec = _mm_add_ps(out.vec, _mm_mul_ps(in.vec, w.vec));
#else
out += in * w;
#endif
}
template <bool origNrm, bool origCol, bool origTc, bool useSSE4>
static void SplinePatchFullQuality(u8 *&dest, u16 *indices, int &count, const SplinePatchLocal &spatch, u32 origVertType, int quality, int maxVertices) {
// Full (mostly) correct tessellation of spline patches.
// Not very fast.
float *knot_u = new float[spatch.count_u + 4];
float *knot_v = new float[spatch.count_v + 4];
spline_knot(spatch.count_u - 1, spatch.type_u, knot_u);
spline_knot(spatch.count_v - 1, spatch.type_v, knot_v);
// Increase tessellation based on the size. Should be approximately right?
int patch_div_s = (spatch.count_u - 3) * spatch.tess_u;
int patch_div_t = (spatch.count_v - 3) * spatch.tess_v;
if (quality > 1) {
// Don't cut below 2, though.
if (patch_div_s > 2) {
patch_div_s /= quality;
}
if (patch_div_t > 2) {
patch_div_t /= quality;
}
}
// Downsample until it fits, in case crazy tessellation factors are sent.
while ((patch_div_s + 1) * (patch_div_t + 1) > maxVertices) {
patch_div_s /= 2;
patch_div_t /= 2;
}
if (patch_div_s < 1) patch_div_s = 1;
if (patch_div_t < 1) patch_div_t = 1;
// First compute all the vertices and put them in an array
SimpleVertex *&vertices = (SimpleVertex*&)dest;
float tu_width = (float)spatch.count_u - 3.0f;
float tv_height = (float)spatch.count_v - 3.0f;
// int max_idx = spatch.count_u * spatch.count_v;
bool computeNormals = spatch.computeNormals;
float one_over_patch_div_s = 1.0f / (float)(patch_div_s);
float one_over_patch_div_t = 1.0f / (float)(patch_div_t);
for (int tile_v = 0; tile_v < patch_div_t + 1; tile_v++) {
float v = (float)tile_v * (float)(spatch.count_v - 3) * one_over_patch_div_t;
if (v < 0.0f)
v = 0.0f;
for (int tile_u = 0; tile_u < patch_div_s + 1; tile_u++) {
float u = (float)tile_u * (float)(spatch.count_u - 3) * one_over_patch_div_s;
if (u < 0.0f)
u = 0.0f;
SimpleVertex *vert = &vertices[tile_v * (patch_div_s + 1) + tile_u];
Vec4f vert_color(0, 0, 0, 0);
Vec3f vert_pos;
vert_pos.SetZero();
Vec3f vert_nrm;
if (origNrm) {
vert_nrm.SetZero();
}
if (origCol) {
vert_color.SetZero();
} else {
memcpy(vert->color, spatch.points[0]->color, 4);
}
if (origTc) {
vert->uv[0] = 0.0f;
vert->uv[1] = 0.0f;
} else {
vert->uv[0] = tu_width * ((float)tile_u * one_over_patch_div_s);
vert->uv[1] = tv_height * ((float)tile_v * one_over_patch_div_t);
}
// Collect influences from surrounding control points.
float u_weights[4];
float v_weights[4];
int iu = (int)u;
int iv = (int)v;
// TODO: Would really like to fix the surrounding logic somehow to get rid of these but I can't quite get it right..
// Without the previous epsilons and with large count_u, we will end up doing an out of bounds access later without these.
if (iu >= spatch.count_u - 3) iu = spatch.count_u - 4;
if (iv >= spatch.count_v - 3) iv = spatch.count_v - 4;
spline_n_4(iu, u, knot_u, u_weights);
spline_n_4(iv, v, knot_v, v_weights);
// Handle degenerate patches. without this, spatch.points[] may read outside the number of initialized points.
int patch_w = std::min(spatch.count_u - iu, 4);
int patch_h = std::min(spatch.count_v - iv, 4);
for (int ii = 0; ii < patch_w; ++ii) {
for (int jj = 0; jj < patch_h; ++jj) {
float u_spline = u_weights[ii];
float v_spline = v_weights[jj];
float f = u_spline * v_spline;
if (f > 0.0f) {
#ifdef _M_SSE
Vec4f fv(_mm_set_ps1(f));
#else
Vec4f fv = Vec4f::AssignToAll(f);
#endif
int idx = spatch.count_u * (iv + jj) + (iu + ii);
/*
if (idx >= max_idx) {
char temp[512];
snprintf(temp, sizeof(temp), "count_u: %d count_v: %d patch_w: %d patch_h: %d ii: %d jj: %d iu: %d iv: %d patch_div_s: %d patch_div_t: %d\n", spatch.count_u, spatch.count_v, patch_w, patch_h, ii, jj, iu, iv, patch_div_s, patch_div_t);
OutputDebugStringA(temp);
Crash();
}*/
SimpleVertex *a = spatch.points[idx];
AccumulateWeighted(vert_pos, a->pos, fv);
if (origTc) {
vert->uv[0] += a->uv[0] * f;
vert->uv[1] += a->uv[1] * f;
}
if (origCol) {
Vec4f a_color = Vec4f::FromRGBA(a->color_32);
AccumulateWeighted(vert_color, a_color, fv);
}
if (origNrm) {
AccumulateWeighted(vert_nrm, a->nrm, fv);
}
}
}
}
vert->pos = vert_pos;
if (origNrm) {
#ifdef _M_SSE
const __m128 normalize = SSENormalizeMultiplier(useSSE4, vert_nrm.vec);
vert_nrm.vec = _mm_mul_ps(vert_nrm.vec, normalize);
#else
vert_nrm.Normalize();
#endif
vert->nrm = vert_nrm;
} else {
vert->nrm.SetZero();
vert->nrm.z = 1.0f;
}
if (origCol) {
vert->color_32 = vert_color.ToRGBA();
}
}
}
delete[] knot_u;
delete[] knot_v;
// Hacky normal generation through central difference.
if (computeNormals && !origNrm) {
#ifdef _M_SSE
const __m128 facing = spatch.patchFacing ? _mm_set_ps1(-1.0f) : _mm_set_ps1(1.0f);
#endif
for (int v = 0; v < patch_div_t + 1; v++) {
Vec3f vl_pos = vertices[v * (patch_div_s + 1)].pos;
Vec3f vc_pos = vertices[v * (patch_div_s + 1)].pos;
for (int u = 0; u < patch_div_s + 1; u++) {
const int t = std::max(0, v - 1);
const int r = std::min(patch_div_s, u + 1);
const int b = std::min(patch_div_t, v + 1);
const Vec3f vr_pos = vertices[v * (patch_div_s + 1) + r].pos;
#ifdef _M_SSE
const __m128 right = _mm_sub_ps(vr_pos.vec, vl_pos.vec);
const Vec3f vb_pos = vertices[b * (patch_div_s + 1) + u].pos;
const Vec3f vt_pos = vertices[t * (patch_div_s + 1) + u].pos;
const __m128 down = _mm_sub_ps(vb_pos.vec, vt_pos.vec);
const __m128 crossed = SSECrossProduct(right, down);
const __m128 normalize = SSENormalizeMultiplier(useSSE4, crossed);
Vec3f finalNrm = _mm_mul_ps(normalize, _mm_mul_ps(crossed, facing));
vertices[v * (patch_div_s + 1) + u].nrm = finalNrm;
#else
const Vec3Packedf &right = vr_pos - vl_pos;
const Vec3Packedf &down = vertices[b * (patch_div_s + 1) + u].pos - vertices[t * (patch_div_s + 1) + u].pos;
vertices[v * (patch_div_s + 1) + u].nrm = Cross(right, down).Normalized();
if (spatch.patchFacing) {
vertices[v * (patch_div_s + 1) + u].nrm *= -1.0f;
}
#endif
// Rotate for the next one to the right.
vl_pos = vc_pos;
vc_pos = vr_pos;
}
}
}
GEPatchPrimType prim_type = spatch.primType;
// Tessellate.
for (int tile_v = 0; tile_v < patch_div_t; ++tile_v) {
for (int tile_u = 0; tile_u < patch_div_s; ++tile_u) {
int idx0 = tile_v * (patch_div_s + 1) + tile_u;
int idx1 = tile_v * (patch_div_s + 1) + tile_u + 1;
int idx2 = (tile_v + 1) * (patch_div_s + 1) + tile_u;
int idx3 = (tile_v + 1) * (patch_div_s + 1) + tile_u + 1;
CopyQuadIndex(indices, prim_type, idx0, idx1, idx2, idx3);
count += 6;
}
}
}
template <bool origNrm, bool origCol, bool origTc>
static inline void SplinePatchFullQualityDispatch4(u8 *&dest, u16 *indices, int &count, const SplinePatchLocal &spatch, u32 origVertType, int quality, int maxVertices) {
if (cpu_info.bSSE4_1)
SplinePatchFullQuality<origNrm, origCol, origTc, true>(dest, indices, count, spatch, origVertType, quality, maxVertices);
else
SplinePatchFullQuality<origNrm, origCol, origTc, false>(dest, indices, count, spatch, origVertType, quality, maxVertices);
}
template <bool origNrm, bool origCol>
static inline void SplinePatchFullQualityDispatch3(u8 *&dest, u16 *indices, int &count, const SplinePatchLocal &spatch, u32 origVertType, int quality, int maxVertices) {
bool origTc = (origVertType & GE_VTYPE_TC_MASK) != 0;
if (origTc)
SplinePatchFullQualityDispatch4<origNrm, origCol, true>(dest, indices, count, spatch, origVertType, quality, maxVertices);
else
SplinePatchFullQualityDispatch4<origNrm, origCol, false>(dest, indices, count, spatch, origVertType, quality, maxVertices);
}
template <bool origNrm>
static inline void SplinePatchFullQualityDispatch2(u8 *&dest, u16 *indices, int &count, const SplinePatchLocal &spatch, u32 origVertType, int quality, int maxVertices) {
bool origCol = (origVertType & GE_VTYPE_COL_MASK) != 0;
if (origCol)
SplinePatchFullQualityDispatch3<origNrm, true>(dest, indices, count, spatch, origVertType, quality, maxVertices);
else
SplinePatchFullQualityDispatch3<origNrm, false>(dest, indices, count, spatch, origVertType, quality, maxVertices);
}
static void SplinePatchFullQualityDispatch(u8 *&dest, u16 *indices, int &count, const SplinePatchLocal &spatch, u32 origVertType, int quality, int maxVertices) {
bool origNrm = (origVertType & GE_VTYPE_NRM_MASK) != 0;
if (origNrm)
SplinePatchFullQualityDispatch2<true>(dest, indices, count, spatch, origVertType, quality, maxVertices);
else
SplinePatchFullQualityDispatch2<false>(dest, indices, count, spatch, origVertType, quality, maxVertices);
}
void TessellateSplinePatch(u8 *&dest, u16 *indices, int &count, const SplinePatchLocal &spatch, u32 origVertType, int maxVertexCount) {
switch (g_Config.iSplineBezierQuality) {
case LOW_QUALITY:
_SplinePatchLowQuality(dest, indices, count, spatch, origVertType);
break;
case MEDIUM_QUALITY:
SplinePatchFullQualityDispatch(dest, indices, count, spatch, origVertType, 2, maxVertexCount);
break;
case HIGH_QUALITY:
SplinePatchFullQualityDispatch(dest, indices, count, spatch, origVertType, 1, maxVertexCount);
break;
}
}
static void _BezierPatchLowQuality(u8 *&dest, u16 *&indices, int &count, int tess_u, int tess_v, const BezierPatch &patch, u32 origVertType) {
const float third = 1.0f / 3.0f;
// Fast and easy way - just draw the control points, generate some very basic normal vector subsitutes.
// Very inaccurate though but okay for Loco Roco. Maybe should keep it as an option.
float u_base = patch.u_index / 3.0f;
float v_base = patch.v_index / 3.0f;
GEPatchPrimType prim_type = patch.primType;
for (int tile_v = 0; tile_v < 3; tile_v++) {
for (int tile_u = 0; tile_u < 3; tile_u++) {
int point_index = tile_u + tile_v * 4;
SimpleVertex v0 = *patch.points[point_index];
SimpleVertex v1 = *patch.points[point_index + 1];
SimpleVertex v2 = *patch.points[point_index + 4];
SimpleVertex v3 = *patch.points[point_index + 5];
// Generate UV. TODO: Do this even if UV specified in control points?
if ((origVertType & GE_VTYPE_TC_MASK) == 0) {
float u = u_base + tile_u * third;
float v = v_base + tile_v * third;
v0.uv[0] = u;
v0.uv[1] = v;
v1.uv[0] = u + third;
v1.uv[1] = v;
v2.uv[0] = u;
v2.uv[1] = v + third;
v3.uv[0] = u + third;
v3.uv[1] = v + third;
}
// Generate normal if lighting is enabled (otherwise there's no point).
// This is a really poor quality algorithm, we get facet normals.
if (patch.computeNormals) {
Vec3Packedf norm = Cross(v1.pos - v0.pos, v2.pos - v0.pos);
norm.Normalize();
if (patch.patchFacing)
norm *= -1.0f;
v0.nrm = norm;
v1.nrm = norm;
v2.nrm = norm;
v3.nrm = norm;
}
int total = patch.index * 3 * 3 * 4; // A patch has 3x3 tiles, and each tiles have 4 vertices.
int tile_index = tile_u + tile_v * 3;
int idx0 = total + tile_index * 4 + 0;
int idx1 = total + tile_index * 4 + 1;
int idx2 = total + tile_index * 4 + 2;
int idx3 = total + tile_index * 4 + 3;
CopyQuad(dest, &v0, &v1, &v2, &v3);
CopyQuadIndex(indices, prim_type, idx0, idx1, idx2, idx3);
count += 6;
}
}
}
template <typename T>
struct PrecomputedCurves {
PrecomputedCurves(int count) {
horiz1 = (T *)AllocateAlignedMemory(count * 4 * sizeof(T), 16);
horiz2 = horiz1 + count * 1;
horiz3 = horiz1 + count * 2;
horiz4 = horiz1 + count * 3;
}
~PrecomputedCurves() {
FreeAlignedMemory(horiz1);
}
T Bernstein3D(int u, float bv) {
return ::Bernstein3D(horiz1[u], horiz2[u], horiz3[u], horiz4[u], bv);
}
T Bernstein3DDerivative(int u, float bv) {
return ::Bernstein3DDerivative(horiz1[u], horiz2[u], horiz3[u], horiz4[u], bv);
}
T *horiz1;
T *horiz2;
T *horiz3;
T *horiz4;
};
static void _BezierPatchHighQuality(u8 *&dest, u16 *&indices, int &count, int tess_u, int tess_v, const BezierPatch &patch, u32 origVertType) {
const float third = 1.0f / 3.0f;
// First compute all the vertices and put them in an array
SimpleVertex *&vertices = (SimpleVertex*&)dest;
PrecomputedCurves<Vec3f> prepos(tess_u + 1);
PrecomputedCurves<Vec4f> precol(tess_u + 1);
PrecomputedCurves<Math3D::Vec2f> pretex(tess_u + 1);
PrecomputedCurves<Vec3f> prederivU(tess_u + 1);
const bool computeNormals = patch.computeNormals;
const bool sampleColors = (origVertType & GE_VTYPE_COL_MASK) != 0;
const bool sampleTexcoords = (origVertType & GE_VTYPE_TC_MASK) != 0;
// Precompute the horizontal curves to we only have to evaluate the vertical ones.
for (int i = 0; i < tess_u + 1; i++) {
float u = ((float)i / (float)tess_u);
prepos.horiz1[i] = Bernstein3D(patch.points[0]->pos, patch.points[1]->pos, patch.points[2]->pos, patch.points[3]->pos, u);
prepos.horiz2[i] = Bernstein3D(patch.points[4]->pos, patch.points[5]->pos, patch.points[6]->pos, patch.points[7]->pos, u);
prepos.horiz3[i] = Bernstein3D(patch.points[8]->pos, patch.points[9]->pos, patch.points[10]->pos, patch.points[11]->pos, u);
prepos.horiz4[i] = Bernstein3D(patch.points[12]->pos, patch.points[13]->pos, patch.points[14]->pos, patch.points[15]->pos, u);
if (sampleColors) {
precol.horiz1[i] = Bernstein3D(patch.points[0]->color_32, patch.points[1]->color_32, patch.points[2]->color_32, patch.points[3]->color_32, u);
precol.horiz2[i] = Bernstein3D(patch.points[4]->color_32, patch.points[5]->color_32, patch.points[6]->color_32, patch.points[7]->color_32, u);
precol.horiz3[i] = Bernstein3D(patch.points[8]->color_32, patch.points[9]->color_32, patch.points[10]->color_32, patch.points[11]->color_32, u);
precol.horiz4[i] = Bernstein3D(patch.points[12]->color_32, patch.points[13]->color_32, patch.points[14]->color_32, patch.points[15]->color_32, u);
}
if (sampleTexcoords) {
pretex.horiz1[i] = Bernstein3D(Math3D::Vec2f(patch.points[0]->uv), Math3D::Vec2f(patch.points[1]->uv), Math3D::Vec2f(patch.points[2]->uv), Math3D::Vec2f(patch.points[3]->uv), u);
pretex.horiz2[i] = Bernstein3D(Math3D::Vec2f(patch.points[4]->uv), Math3D::Vec2f(patch.points[5]->uv), Math3D::Vec2f(patch.points[6]->uv), Math3D::Vec2f(patch.points[7]->uv), u);
pretex.horiz3[i] = Bernstein3D(Math3D::Vec2f(patch.points[8]->uv), Math3D::Vec2f(patch.points[9]->uv), Math3D::Vec2f(patch.points[10]->uv), Math3D::Vec2f(patch.points[11]->uv), u);
pretex.horiz4[i] = Bernstein3D(Math3D::Vec2f(patch.points[12]->uv), Math3D::Vec2f(patch.points[13]->uv), Math3D::Vec2f(patch.points[14]->uv), Math3D::Vec2f(patch.points[15]->uv), u);
}
if (computeNormals) {
prederivU.horiz1[i] = Bernstein3DDerivative(patch.points[0]->pos, patch.points[1]->pos, patch.points[2]->pos, patch.points[3]->pos, u);
prederivU.horiz2[i] = Bernstein3DDerivative(patch.points[4]->pos, patch.points[5]->pos, patch.points[6]->pos, patch.points[7]->pos, u);
prederivU.horiz3[i] = Bernstein3DDerivative(patch.points[8]->pos, patch.points[9]->pos, patch.points[10]->pos, patch.points[11]->pos, u);
prederivU.horiz4[i] = Bernstein3DDerivative(patch.points[12]->pos, patch.points[13]->pos, patch.points[14]->pos, patch.points[15]->pos, u);
}
}
for (int tile_v = 0; tile_v < tess_v + 1; ++tile_v) {
for (int tile_u = 0; tile_u < tess_u + 1; ++tile_u) {
float u = ((float)tile_u / (float)tess_u);
float v = ((float)tile_v / (float)tess_v);
float bv = v;
SimpleVertex &vert = vertices[tile_v * (tess_u + 1) + tile_u];
if (computeNormals) {
const Vec3f derivU = prederivU.Bernstein3D(tile_u, bv);
const Vec3f derivV = prepos.Bernstein3DDerivative(tile_u, bv);
vert.nrm = Cross(derivU, derivV).Normalized();
if (patch.patchFacing)
vert.nrm *= -1.0f;
} else {
vert.nrm.SetZero();
}
vert.pos = prepos.Bernstein3D(tile_u, bv);
if (!sampleTexcoords) {
// Generate texcoord
vert.uv[0] = u + patch.u_index * third;
vert.uv[1] = v + patch.v_index * third;
} else {
// Sample UV from control points
const Math3D::Vec2f res = pretex.Bernstein3D(tile_u, bv);
vert.uv[0] = res.x;
vert.uv[1] = res.y;
}
if (sampleColors) {
vert.color_32 = precol.Bernstein3D(tile_u, bv).ToRGBA();
} else {
memcpy(vert.color, patch.points[0]->color, 4);
}
}
}
GEPatchPrimType prim_type = patch.primType;
// Combine the vertices into triangles.
for (int tile_v = 0; tile_v < tess_v; ++tile_v) {
for (int tile_u = 0; tile_u < tess_u; ++tile_u) {
int total = patch.index * (tess_u + 1) * (tess_v + 1);
int idx0 = total + tile_v * (tess_u + 1) + tile_u;
int idx1 = total + tile_v * (tess_u + 1) + tile_u + 1;
int idx2 = total + (tile_v + 1) * (tess_u + 1) + tile_u;
int idx3 = total + (tile_v + 1) * (tess_u + 1) + tile_u + 1;
CopyQuadIndex(indices, prim_type, idx0, idx1, idx2, idx3);
count += 6;
}
}
dest += (tess_u + 1) * (tess_v + 1) * sizeof(SimpleVertex);
}
// Prepare mesh of one patch for "Instanced Tessellation".
static void TessellateBezierPatchHardware(u8 *&dest, u16 *indices, int &count, int tess_u, int tess_v, GEPatchPrimType primType) {
SimpleVertex *&vertices = (SimpleVertex*&)dest;
float inv_u = 1.0f / (float)tess_u;
float inv_v = 1.0f / (float)tess_v;
// Generating simple input vertices for the bezier-computing vertex shader.
for (int tile_v = 0; tile_v < tess_v + 1; ++tile_v) {
for (int tile_u = 0; tile_u < tess_u + 1; ++tile_u) {
SimpleVertex &vert = vertices[tile_v * (tess_u + 1) + tile_u];
vert.pos.x = (float)tile_u * inv_u;
vert.pos.y = (float)tile_v * inv_v;
}
}
// Combine the vertices into triangles.
for (int tile_v = 0; tile_v < tess_v; ++tile_v) {
for (int tile_u = 0; tile_u < tess_u; ++tile_u) {
int idx0 = tile_v * (tess_u + 1) + tile_u;
int idx1 = tile_v * (tess_u + 1) + tile_u + 1;
int idx2 = (tile_v + 1) * (tess_u + 1) + tile_u;
int idx3 = (tile_v + 1) * (tess_u + 1) + tile_u + 1;
CopyQuadIndex(indices, primType, idx0, idx1, idx2, idx3);
count += 6;
}
}
}
void TessellateBezierPatch(u8 *&dest, u16 *&indices, int &count, int tess_u, int tess_v, const BezierPatch &patch, u32 origVertType) {
switch (g_Config.iSplineBezierQuality) {
case LOW_QUALITY:
_BezierPatchLowQuality(dest, indices, count, tess_u, tess_v, patch, origVertType);
break;
case MEDIUM_QUALITY:
_BezierPatchHighQuality(dest, indices, count, tess_u / 2, tess_v / 2, patch, origVertType);
break;
case HIGH_QUALITY:
_BezierPatchHighQuality(dest, indices, count, tess_u, tess_v, patch, origVertType);
break;
}
}
class IndexConverter {
private:
union {
const void *indices;
const u8 *indices8;
const u16 *indices16;
const u32 *indices32;
};
u32 indexType;
public:
IndexConverter(u32 vertType, const void *indices) : indices(indices), indexType(vertType & GE_VTYPE_IDX_MASK) {}
inline u32 convert(u32 index) const {
switch (indexType) {
case GE_VTYPE_IDX_8BIT:
return indices8[index];
case GE_VTYPE_IDX_16BIT:
return indices16[index];
case GE_VTYPE_IDX_32BIT:
return indices32[index];
}
return index;
}
};
// This maps GEPatchPrimType to GEPrimitiveType.
const GEPrimitiveType primType[] = { GE_PRIM_TRIANGLES, GE_PRIM_LINES, GE_PRIM_POINTS, GE_PRIM_POINTS };
void DrawEngineCommon::SubmitSpline(const void *control_points, const void *indices, int tess_u, int tess_v, int count_u, int count_v, int type_u, int type_v, GEPatchPrimType prim_type, bool computeNormals, bool patchFacing, u32 vertType, int *bytesRead) {
PROFILE_THIS_SCOPE("spline");
DispatchFlush();
u16 index_lower_bound = 0;
u16 index_upper_bound = count_u * count_v - 1;
IndexConverter idxConv(vertType, indices);
if (indices)
GetIndexBounds(indices, count_u * count_v, vertType, &index_lower_bound, &index_upper_bound);
VertexDecoder *origVDecoder = GetVertexDecoder((vertType & 0xFFFFFF) | (gstate.getUVGenMode() << 24));
*bytesRead = count_u * count_v * origVDecoder->VertexSize();
// Real hardware seems to draw nothing when given < 4 either U or V.
if (count_u < 4 || count_v < 4) {
return;
}
// Simplify away bones and morph before proceeding
SimpleVertex *simplified_control_points = (SimpleVertex *)(decoded + 65536 * 12);
u8 *temp_buffer = decoded + 65536 * 18;
u32 origVertType = vertType;
vertType = NormalizeVertices((u8 *)simplified_control_points, temp_buffer, (u8 *)control_points, index_lower_bound, index_upper_bound, vertType);
VertexDecoder *vdecoder = GetVertexDecoder(vertType);
int vertexSize = vdecoder->VertexSize();
if (vertexSize != sizeof(SimpleVertex)) {
ERROR_LOG(G3D, "Something went really wrong, vertex size: %i vs %i", vertexSize, (int)sizeof(SimpleVertex));
}
// TODO: Do something less idiotic to manage this buffer
SimpleVertex **points = new SimpleVertex *[count_u * count_v];
// Make an array of pointers to the control points, to get rid of indices.
for (int idx = 0; idx < count_u * count_v; idx++) {
points[idx] = simplified_control_points + (indices ? idxConv.convert(idx) : idx);
}
int count = 0;
u8 *dest = splineBuffer;
SplinePatchLocal patch;
patch.tess_u = tess_u;
patch.tess_v = tess_v;
patch.type_u = type_u;
patch.type_v = type_v;
patch.count_u = count_u;
patch.count_v = count_v;
patch.points = points;
patch.computeNormals = computeNormals;
patch.primType = prim_type;
patch.patchFacing = patchFacing;
if (g_Config.bHardwareTessellation && g_Config.bHardwareTransform && !g_Config.bSoftwareRendering) {
float *pos = (float*)(decoded + 65536 * 18); // Size 3 float
float *tex = pos + count_u * count_v * 3; // Size 3 float
float *col = tex + count_u * count_v * 3; // Size 4 float
const bool hasColor = (origVertType & GE_VTYPE_COL_MASK) != 0;
const bool hasTexCoords = (origVertType & GE_VTYPE_TC_MASK) != 0;
for (int idx = 0; idx < count_u * count_v; idx++) {
memcpy(pos + idx * 3, points[idx]->pos.AsArray(), 3 * sizeof(float));
if (hasTexCoords)
memcpy(tex + idx * 3, points[idx]->uv, 2 * sizeof(float));
if (hasColor)
memcpy(col + idx * 4, Vec4f::FromRGBA(points[idx]->color_32).AsArray(), 4 * sizeof(float));
}
if (!hasColor)
memcpy(col, Vec4f::FromRGBA(points[0]->color_32).AsArray(), 4 * sizeof(float));
tessDataTransfer->SendDataToShader(pos, tex, col, count_u * count_v, hasColor, hasTexCoords);
TessellateSplinePatchHardware(dest, quadIndices_, count, patch);
numPatches = (count_u - 3) * (count_v - 3);
} else {
int maxVertexCount = SPLINE_BUFFER_SIZE / vertexSize;
TessellateSplinePatch(dest, quadIndices_, count, patch, origVertType, maxVertexCount);
}
delete[] points;
u32 vertTypeWithIndex16 = (vertType & ~GE_VTYPE_IDX_MASK) | GE_VTYPE_IDX_16BIT;
UVScale prevUVScale;
if ((origVertType & GE_VTYPE_TC_MASK) != 0) {
// We scaled during Normalize already so let's turn it off when drawing.
prevUVScale = gstate_c.uv;
gstate_c.uv.uScale = 1.0f;
gstate_c.uv.vScale = 1.0f;
gstate_c.uv.uOff = 0.0f;
gstate_c.uv.vOff = 0.0f;
}
int generatedBytesRead;
DispatchSubmitPrim(splineBuffer, quadIndices_, primType[prim_type], count, vertTypeWithIndex16, &generatedBytesRead);
DispatchFlush();
if ((origVertType & GE_VTYPE_TC_MASK) != 0) {
gstate_c.uv = prevUVScale;
}
}
void DrawEngineCommon::SubmitBezier(const void *control_points, const void *indices, int tess_u, int tess_v, int count_u, int count_v, GEPatchPrimType prim_type, bool computeNormals, bool patchFacing, u32 vertType, int *bytesRead) {
PROFILE_THIS_SCOPE("bezier");
DispatchFlush();
u16 index_lower_bound = 0;
u16 index_upper_bound = count_u * count_v - 1;
IndexConverter idxConv(vertType, indices);
if (indices)
GetIndexBounds(indices, count_u*count_v, vertType, &index_lower_bound, &index_upper_bound);
VertexDecoder *origVDecoder = GetVertexDecoder((vertType & 0xFFFFFF) | (gstate.getUVGenMode() << 24));
*bytesRead = count_u * count_v * origVDecoder->VertexSize();
// Real hardware seems to draw nothing when given < 4 either U or V.
// This would result in num_patches_u / num_patches_v being 0.
if (count_u < 4 || count_v < 4) {
return;
}
// Simplify away bones and morph before proceeding
// There are normally not a lot of control points so just splitting decoded should be reasonably safe, although not great.
SimpleVertex *simplified_control_points = (SimpleVertex *)(decoded + 65536 * 12);
u8 *temp_buffer = decoded + 65536 * 18;
u32 origVertType = vertType;
vertType = NormalizeVertices((u8 *)simplified_control_points, temp_buffer, (u8 *)control_points, index_lower_bound, index_upper_bound, vertType);
VertexDecoder *vdecoder = GetVertexDecoder(vertType);
int vertexSize = vdecoder->VertexSize();
if (vertexSize != sizeof(SimpleVertex)) {
ERROR_LOG(G3D, "Something went really wrong, vertex size: %i vs %i", vertexSize, (int)sizeof(SimpleVertex));
}
float *pos = (float*)(decoded + 65536 * 18); // Size 3 float
float *tex = pos + count_u * count_v * 3; // Size 3 float
float *col = tex + count_u * count_v * 3; // Size 4 float
const bool hasColor = (origVertType & GE_VTYPE_COL_MASK) != 0;
const bool hasTexCoords = (origVertType & GE_VTYPE_TC_MASK) != 0;
// Bezier patches share less control points than spline patches. Otherwise they are pretty much the same (except bezier don't support the open/close thing)
int num_patches_u = (count_u - 1) / 3;
int num_patches_v = (count_v - 1) / 3;
BezierPatch *patches = nullptr;
if (g_Config.bHardwareTessellation && g_Config.bHardwareTransform && !g_Config.bSoftwareRendering) {
tessDataTransfer->PrepareBuffers(pos, tex, col, count_u * count_v, hasColor, hasTexCoords);
for (int idx = 0; idx < count_u * count_v; idx++) {
SimpleVertex *point = simplified_control_points + (indices ? idxConv.convert(idx) : idx);
memcpy(pos + idx * 3, point->pos.AsArray(), 3 * sizeof(float));
if (hasTexCoords)
memcpy(tex + idx * 3, point->uv, 2 * sizeof(float));
if (hasColor)
memcpy(col + idx * 4, Vec4f::FromRGBA(point->color_32).AsArray(), 4 * sizeof(float));
}
if (!hasColor) {
SimpleVertex *point = simplified_control_points + (indices ? idxConv.convert(0) : 0);
memcpy(col, Vec4f::FromRGBA(point->color_32).AsArray(), 4 * sizeof(float));
}
} else {
patches = new BezierPatch[num_patches_u * num_patches_v];
for (int patch_u = 0; patch_u < num_patches_u; patch_u++) {
for (int patch_v = 0; patch_v < num_patches_v; patch_v++) {
BezierPatch& patch = patches[patch_u + patch_v * num_patches_u];
for (int point = 0; point < 16; ++point) {
int idx = (patch_u * 3 + point % 4) + (patch_v * 3 + point / 4) * count_u;
patch.points[point] = simplified_control_points + (indices ? idxConv.convert(idx) : idx);
}
patch.u_index = patch_u * 3;
patch.v_index = patch_v * 3;
patch.index = patch_v * num_patches_u + patch_u;
patch.primType = prim_type;
patch.computeNormals = computeNormals;
patch.patchFacing = patchFacing;
}
}
}
int count = 0;
u8 *dest = splineBuffer;
// We shouldn't really split up into separate 4x4 patches, instead we should do something that works
// like the splines, so we subdivide across the whole "mega-patch".
// If specified as 0, uses 1.
if (tess_u < 1) {
tess_u = 1;
}
if (tess_v < 1) {
tess_v = 1;
}
u16 *inds = quadIndices_;
if (g_Config.bHardwareTessellation && g_Config.bHardwareTransform && !g_Config.bSoftwareRendering) {
tessDataTransfer->SendDataToShader(pos, tex, col, count_u * count_v, hasColor, hasTexCoords);
TessellateBezierPatchHardware(dest, inds, count, tess_u, tess_v, prim_type);
numPatches = num_patches_u * num_patches_v;
} else {
int maxVertices = SPLINE_BUFFER_SIZE / vertexSize;
// Downsample until it fits, in case crazy tessellation factors are sent.
while ((tess_u + 1) * (tess_v + 1) * num_patches_u * num_patches_v > maxVertices) {
tess_u /= 2;
tess_v /= 2;
}
for (int patch_idx = 0; patch_idx < num_patches_u*num_patches_v; ++patch_idx) {
const BezierPatch &patch = patches[patch_idx];
TessellateBezierPatch(dest, inds, count, tess_u, tess_v, patch, origVertType);
}
delete[] patches;
}
u32 vertTypeWithIndex16 = (vertType & ~GE_VTYPE_IDX_MASK) | GE_VTYPE_IDX_16BIT;
UVScale prevUVScale;
if (origVertType & GE_VTYPE_TC_MASK) {
// We scaled during Normalize already so let's turn it off when drawing.
prevUVScale = gstate_c.uv;
gstate_c.uv.uScale = 1.0f;
gstate_c.uv.vScale = 1.0f;
gstate_c.uv.uOff = 0;
gstate_c.uv.vOff = 0;
}
int generatedBytesRead;
DispatchSubmitPrim(splineBuffer, quadIndices_, primType[prim_type], count, vertTypeWithIndex16, &generatedBytesRead);
DispatchFlush();
if (origVertType & GE_VTYPE_TC_MASK) {
gstate_c.uv = prevUVScale;
}
}
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