ebiten/internal/graphics/vertex.go
Hajime Hoshi cb73230301 graphics: Revive the special allocating method for vertices for Wasm
It looks like the allocation cost is pretty high even on Wasm.
Revive the special method not only on GopherJS but also on Wasm.

examples/sprites kept 30FPS without this fix, but keeps 35FPS with
this fix, on Hajime's MacBook Pro 2020 (macOS Catalina 10.15.6).

Updates #797
2020-09-21 04:21:21 +09:00

141 lines
3.2 KiB
Go

// Copyright 2019 The Ebiten Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package graphics
import (
"github.com/hajimehoshi/ebiten/internal/web"
)
const (
ShaderImageNum = 4
// PreservedUniformVariablesNum represents the number of preserved uniform variables.
// Any shaders in Ebiten must have these uniform variables.
PreservedUniformVariablesNum = 1 + // the destination texture size
1 + // the texture sizes array
1 + // the offsets array of the second and the following images
1 + // the texture source region's origin
1 // the texture source region's size
DestinationTextureSizeUniformVariableIndex = 0
TextureSizesUniformVariableIndex = 1
TextureSourceOffsetsUniformVariableIndex = 2
TextureSourceRegionOriginUniformVariableIndex = 3
TextureSourceRegionSizeUniformVariableIndex = 4
)
const (
IndicesNum = (1 << 16) / 3 * 3 // Adjust num for triangles.
VertexFloatNum = 8
)
var (
quadIndices = []uint16{0, 1, 2, 1, 2, 3}
)
func QuadIndices() []uint16 {
return quadIndices
}
var (
theVerticesBackend = &verticesBackend{
backend: make([]float32, VertexFloatNum*1024),
}
)
type verticesBackend struct {
backend []float32
head int
}
func (v *verticesBackend) slice(n int, last bool) []float32 {
// As this is called only from GopherJS, mutex is not required.
need := n * VertexFloatNum
if l := len(v.backend); v.head+need > l {
for v.head+need > l {
l *= 2
}
v.backend = make([]float32, l)
v.head = 0
}
s := v.backend[v.head : v.head+need]
if last {
// If last is true, the vertices backend is sent to GPU and it is fine to reuse the slice.
v.head = 0
} else {
v.head += need
}
return s
}
func vertexSlice(n int, last bool) []float32 {
if web.IsBrowser() {
// In GopherJS and Wasm, allocating memory by make is expensive. Use the backend instead.
return theVerticesBackend.slice(n, last)
}
return make([]float32, n*VertexFloatNum)
}
func QuadVertices(sx0, sy0, sx1, sy1 float32, a, b, c, d, tx, ty float32, cr, cg, cb, ca float32, last bool) []float32 {
x := sx1 - sx0
y := sy1 - sy0
ax, by, cx, dy := a*x, b*y, c*x, d*y
u0, v0, u1, v1 := float32(sx0), float32(sy0), float32(sx1), float32(sy1)
// This function is very performance-sensitive and implement in a very dumb way.
vs := vertexSlice(4, last)
_ = vs[:32]
vs[0] = tx
vs[1] = ty
vs[2] = u0
vs[3] = v0
vs[4] = cr
vs[5] = cg
vs[6] = cb
vs[7] = ca
vs[8] = ax + tx
vs[9] = cx + ty
vs[10] = u1
vs[11] = v0
vs[12] = cr
vs[13] = cg
vs[14] = cb
vs[15] = ca
vs[16] = by + tx
vs[17] = dy + ty
vs[18] = u0
vs[19] = v1
vs[20] = cr
vs[21] = cg
vs[22] = cb
vs[23] = ca
vs[24] = ax + by + tx
vs[25] = cx + dy + ty
vs[26] = u1
vs[27] = v1
vs[28] = cr
vs[29] = cg
vs[30] = cb
vs[31] = ca
return vs
}