mirror of
https://git.sr.ht/~eliasnaur/gio
synced 2026-07-07 02:15:34 +00:00
Elias Naur
@@ -0,0 +1,76 @@
|
||||
// SPDX-License-Identifier: Unlicense OR MIT
|
||||
|
||||
package gpu
|
||||
|
||||
import (
|
||||
"image"
|
||||
)
|
||||
|
||||
// genAreaLUT generates the lookup table conpatible with the stencilFSrc
|
||||
// fragment shaders. The table contains the area of a pixel square above
|
||||
// a line. The square has area 1 and is centered in (0, 0).
|
||||
// The y-axis intersection of the line in [-8;+8] is specified by the
|
||||
// first coordinate.
|
||||
// The slope of the line [0;16] is specified by the second coordinate.
|
||||
func genAreaLUT(width, height int) *image.Gray {
|
||||
lut := image.NewGray(image.Rectangle{Max: image.Point{X: width, Y: height}})
|
||||
for v := 0; v < height; v++ {
|
||||
a := float32(v) * 16 / float32(height)
|
||||
for u := 0; u < width; u++ {
|
||||
var area float32
|
||||
switch u {
|
||||
case 0:
|
||||
area = 1.0
|
||||
case width - 1:
|
||||
area = 0.0
|
||||
default:
|
||||
b := (float32(u) - float32(width)/2) / 16
|
||||
// f(x) = ax+b.
|
||||
area = computeLineArea(a, b)
|
||||
}
|
||||
lut.Pix[v*height+u] = uint8(area*255 + 0.5)
|
||||
}
|
||||
}
|
||||
return lut
|
||||
}
|
||||
|
||||
func computeLineArea(a, b float32) float32 {
|
||||
// Compute intersections with the square edges.
|
||||
// Right and left.
|
||||
ry := a*+0.5 + b
|
||||
ly := a*-0.5 + b
|
||||
// Top and bottom.
|
||||
tx := (+0.5 - b) / a
|
||||
bx := (-0.5 - b) / a
|
||||
// The line will intersect zero or two edges.
|
||||
if ry <= -0.5 {
|
||||
// Line is below the square.
|
||||
return 1.0
|
||||
}
|
||||
if ly >= 0.5 {
|
||||
// Line is above the square.
|
||||
return 0.0
|
||||
}
|
||||
// The slope is positive, so there are only 4 possible
|
||||
// pairs of edges: (bottom, right), (left, right),
|
||||
// (bottom, top), (left, top).
|
||||
if ry <= 0.5 {
|
||||
// Intersection with right edge.
|
||||
if ly <= -0.5 {
|
||||
// (bottom, right).
|
||||
return 1.0 - (0.5-bx)*(ry-(-0.5))/2
|
||||
} else {
|
||||
// (left, right).
|
||||
return 1.0*(0.5-ry) + 1.0*(ry-ly)/2
|
||||
}
|
||||
} else {
|
||||
// Intersection with top edge.
|
||||
if ly <= -0.5 {
|
||||
// (bottom, top).
|
||||
return (bx-(-0.5))*1.0 + (tx-bx)*1.0/2
|
||||
} else {
|
||||
// (left, top).
|
||||
return (tx - (-0.5)) * (0.5 - ly) / 2
|
||||
}
|
||||
}
|
||||
}
|
||||
File diff suppressed because it is too large
Load Diff
@@ -0,0 +1,85 @@
|
||||
// SPDX-License-Identifier: Unlicense OR MIT
|
||||
|
||||
package gpu
|
||||
|
||||
import (
|
||||
"image"
|
||||
)
|
||||
|
||||
// packer packs a set of many smaller rectangles into
|
||||
// much fewer larger atlases.
|
||||
type packer struct {
|
||||
maxDim int
|
||||
spaces []image.Rectangle
|
||||
|
||||
sizes []image.Point
|
||||
pos image.Point
|
||||
}
|
||||
|
||||
type placement struct {
|
||||
Idx int
|
||||
Pos image.Point
|
||||
}
|
||||
|
||||
// add adds the given rectangle to the atlases and
|
||||
// return the allocated position.
|
||||
func (p *packer) add(s image.Point) (placement, bool) {
|
||||
if place, ok := p.tryAdd(s); ok {
|
||||
return place, true
|
||||
}
|
||||
p.newPage()
|
||||
return p.tryAdd(s)
|
||||
}
|
||||
|
||||
func (p *packer) clear() {
|
||||
p.sizes = p.sizes[:0]
|
||||
p.spaces = p.spaces[:0]
|
||||
}
|
||||
|
||||
func (p *packer) newPage() {
|
||||
p.pos = image.Point{}
|
||||
p.sizes = append(p.sizes, image.Point{})
|
||||
p.spaces = p.spaces[:0]
|
||||
p.spaces = append(p.spaces, image.Rectangle{
|
||||
Max: image.Point{X: p.maxDim, Y: p.maxDim},
|
||||
})
|
||||
}
|
||||
|
||||
func (p *packer) tryAdd(s image.Point) (placement, bool) {
|
||||
// Go backwards to prioritize smaller spaces first.
|
||||
for i := len(p.spaces) - 1; i >= 0; i-- {
|
||||
space := p.spaces[i]
|
||||
rightSpace := space.Dx() - s.X
|
||||
bottomSpace := space.Dy() - s.Y
|
||||
if rightSpace >= 0 && bottomSpace >= 0 {
|
||||
// Remove space.
|
||||
p.spaces[i] = p.spaces[len(p.spaces)-1]
|
||||
p.spaces = p.spaces[:len(p.spaces)-1]
|
||||
// Put s in the top left corner and add the (at most)
|
||||
// two smaller spaces.
|
||||
pos := space.Min
|
||||
if bottomSpace > 0 {
|
||||
p.spaces = append(p.spaces, image.Rectangle{
|
||||
Min: image.Point{X: pos.X, Y: pos.Y + s.Y},
|
||||
Max: image.Point{X: space.Max.X, Y: space.Max.Y},
|
||||
})
|
||||
}
|
||||
if rightSpace > 0 {
|
||||
p.spaces = append(p.spaces, image.Rectangle{
|
||||
Min: image.Point{X: pos.X + s.X, Y: pos.Y},
|
||||
Max: image.Point{X: space.Max.X, Y: pos.Y + s.Y},
|
||||
})
|
||||
}
|
||||
idx := len(p.sizes) - 1
|
||||
size := &p.sizes[idx]
|
||||
if x := pos.X + s.X; x > size.X {
|
||||
size.X = x
|
||||
}
|
||||
if y := pos.Y + s.Y; y > size.Y {
|
||||
size.Y = y
|
||||
}
|
||||
return placement{Idx: idx, Pos: pos}, true
|
||||
}
|
||||
}
|
||||
return placement{}, false
|
||||
}
|
||||
@@ -0,0 +1,596 @@
|
||||
// SPDX-License-Identifier: Unlicense OR MIT
|
||||
|
||||
package gpu
|
||||
|
||||
// GPU accelerated path drawing using the algorithms from
|
||||
// Pathfinder (https://github.com/pcwalton/pathfinder).
|
||||
|
||||
import (
|
||||
"image"
|
||||
"unsafe"
|
||||
|
||||
"gioui.org/ui/app/internal/gl"
|
||||
"gioui.org/ui/f32"
|
||||
"gioui.org/ui/internal/path"
|
||||
)
|
||||
|
||||
type pather struct {
|
||||
ctx *gl.Functions
|
||||
|
||||
viewport image.Point
|
||||
|
||||
stenciler *stenciler
|
||||
coverer *coverer
|
||||
}
|
||||
|
||||
type coverer struct {
|
||||
ctx *gl.Functions
|
||||
prog [2]gl.Program
|
||||
vars [2]struct {
|
||||
z gl.Uniform
|
||||
uScale, uOffset gl.Uniform
|
||||
uUVScale, uUVOffset gl.Uniform
|
||||
uCoverUVScale, uCoverUVOffset gl.Uniform
|
||||
uColor gl.Uniform
|
||||
}
|
||||
}
|
||||
|
||||
type stenciler struct {
|
||||
ctx *gl.Functions
|
||||
defFBO gl.Framebuffer
|
||||
indexBufQuads int
|
||||
prog gl.Program
|
||||
iprog gl.Program
|
||||
fbos fboSet
|
||||
intersections fboSet
|
||||
uScale, uOffset gl.Uniform
|
||||
uPathOffset gl.Uniform
|
||||
uIntersectUVOffset gl.Uniform
|
||||
uIntersectUVScale gl.Uniform
|
||||
indexBuf gl.Buffer
|
||||
areaLUT gl.Texture
|
||||
}
|
||||
|
||||
type fboSet struct {
|
||||
fbos []stencilFBO
|
||||
}
|
||||
|
||||
type stencilFBO struct {
|
||||
size image.Point
|
||||
fbo gl.Framebuffer
|
||||
tex gl.Texture
|
||||
}
|
||||
|
||||
type pathData struct {
|
||||
ncurves int
|
||||
data gl.Buffer
|
||||
}
|
||||
|
||||
var (
|
||||
pathAttribs = []string{"corner", "maxy", "from", "ctrl", "to"}
|
||||
attribPathCorner gl.Attrib = 0
|
||||
attribPathMaxY gl.Attrib = 1
|
||||
attribPathFrom gl.Attrib = 2
|
||||
attribPathCtrl gl.Attrib = 3
|
||||
attribPathTo gl.Attrib = 4
|
||||
|
||||
intersectAttribs = []string{"pos", "uv"}
|
||||
)
|
||||
|
||||
func newPather(ctx *gl.Functions) *pather {
|
||||
return &pather{
|
||||
ctx: ctx,
|
||||
stenciler: newStenciler(ctx),
|
||||
coverer: newCoverer(ctx),
|
||||
}
|
||||
}
|
||||
|
||||
func newCoverer(ctx *gl.Functions) *coverer {
|
||||
prog, err := createColorPrograms(ctx, coverVSrc, coverFSrc)
|
||||
if err != nil {
|
||||
panic(err)
|
||||
}
|
||||
c := &coverer{
|
||||
ctx: ctx,
|
||||
prog: prog,
|
||||
}
|
||||
for i, prog := range prog {
|
||||
ctx.UseProgram(prog)
|
||||
switch materialType(i) {
|
||||
case materialTexture:
|
||||
uTex := gl.GetUniformLocation(ctx, prog, "tex")
|
||||
ctx.Uniform1i(uTex, 0)
|
||||
c.vars[i].uUVScale = gl.GetUniformLocation(ctx, prog, "uvScale")
|
||||
c.vars[i].uUVOffset = gl.GetUniformLocation(ctx, prog, "uvOffset")
|
||||
case materialColor:
|
||||
c.vars[i].uColor = gl.GetUniformLocation(ctx, prog, "color")
|
||||
}
|
||||
uCover := gl.GetUniformLocation(ctx, prog, "cover")
|
||||
ctx.Uniform1i(uCover, 1)
|
||||
c.vars[i].z = gl.GetUniformLocation(ctx, prog, "z")
|
||||
c.vars[i].uScale = gl.GetUniformLocation(ctx, prog, "scale")
|
||||
c.vars[i].uOffset = gl.GetUniformLocation(ctx, prog, "offset")
|
||||
c.vars[i].uCoverUVScale = gl.GetUniformLocation(ctx, prog, "uvCoverScale")
|
||||
c.vars[i].uCoverUVOffset = gl.GetUniformLocation(ctx, prog, "uvCoverOffset")
|
||||
}
|
||||
return c
|
||||
}
|
||||
|
||||
func newStenciler(ctx *gl.Functions) *stenciler {
|
||||
defFBO := gl.Framebuffer(ctx.GetInteger(gl.FRAMEBUFFER_BINDING))
|
||||
prog, err := gl.CreateProgram(ctx, stencilVSrc, stencilFSrc, pathAttribs)
|
||||
if err != nil {
|
||||
panic(err)
|
||||
}
|
||||
uAreaLUT := gl.GetUniformLocation(ctx, prog, "areaLUT")
|
||||
ctx.UseProgram(prog)
|
||||
ctx.Uniform1i(uAreaLUT, 0)
|
||||
areaLUT, err := loadLUT(ctx, genAreaLUT(256, 256))
|
||||
if err != nil {
|
||||
panic(err)
|
||||
}
|
||||
iprog, err := gl.CreateProgram(ctx, intersectVSrc, intersectFSrc, intersectAttribs)
|
||||
if err != nil {
|
||||
panic(err)
|
||||
}
|
||||
coverLoc := gl.GetUniformLocation(ctx, iprog, "cover")
|
||||
ctx.UseProgram(iprog)
|
||||
ctx.Uniform1i(coverLoc, 0)
|
||||
return &stenciler{
|
||||
ctx: ctx,
|
||||
defFBO: defFBO,
|
||||
prog: prog,
|
||||
iprog: iprog,
|
||||
areaLUT: areaLUT,
|
||||
uScale: gl.GetUniformLocation(ctx, prog, "scale"),
|
||||
uOffset: gl.GetUniformLocation(ctx, prog, "offset"),
|
||||
uPathOffset: gl.GetUniformLocation(ctx, prog, "pathOffset"),
|
||||
uIntersectUVScale: gl.GetUniformLocation(ctx, iprog, "uvScale"),
|
||||
uIntersectUVOffset: gl.GetUniformLocation(ctx, iprog, "uvOffset"),
|
||||
indexBuf: ctx.CreateBuffer(),
|
||||
}
|
||||
}
|
||||
|
||||
func (s *fboSet) resize(ctx *gl.Functions, sizes []image.Point, internalFormat int, format, ty gl.Enum) {
|
||||
// Add fbos.
|
||||
for i := len(s.fbos); i < len(sizes); i++ {
|
||||
tex := ctx.CreateTexture()
|
||||
ctx.BindTexture(gl.TEXTURE_2D, tex)
|
||||
ctx.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
|
||||
ctx.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
|
||||
ctx.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST)
|
||||
ctx.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
|
||||
fbo := ctx.CreateFramebuffer()
|
||||
s.fbos = append(s.fbos, stencilFBO{
|
||||
fbo: fbo,
|
||||
tex: tex,
|
||||
})
|
||||
}
|
||||
// Resize fbos.
|
||||
for i, sz := range sizes {
|
||||
f := &s.fbos[i]
|
||||
// Resizing or recreating FBOs can introduce rendering stalls.
|
||||
// Avoid if the space waste is not too high.
|
||||
resize := sz.X > f.size.X || sz.Y > f.size.Y
|
||||
waste := float32(sz.X*sz.Y) / float32(f.size.X*f.size.Y)
|
||||
resize = resize || waste > 1.2
|
||||
if resize {
|
||||
f.size = sz
|
||||
ctx.BindTexture(gl.TEXTURE_2D, f.tex)
|
||||
ctx.TexImage2D(gl.TEXTURE_2D, 0, internalFormat, sz.X, sz.Y, format, ty, nil)
|
||||
ctx.BindFramebuffer(gl.FRAMEBUFFER, f.fbo)
|
||||
ctx.FramebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, f.tex, 0)
|
||||
}
|
||||
}
|
||||
// Delete extra fbos.
|
||||
s.delete(ctx, len(sizes))
|
||||
}
|
||||
|
||||
func (s *fboSet) invalidate(ctx *gl.Functions) {
|
||||
for _, f := range s.fbos {
|
||||
ctx.BindFramebuffer(gl.FRAMEBUFFER, f.fbo)
|
||||
ctx.InvalidateFramebuffer(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0)
|
||||
}
|
||||
}
|
||||
|
||||
func (s *fboSet) delete(ctx *gl.Functions, idx int) {
|
||||
for i := idx; i < len(s.fbos); i++ {
|
||||
f := s.fbos[i]
|
||||
ctx.DeleteFramebuffer(f.fbo)
|
||||
ctx.DeleteTexture(f.tex)
|
||||
}
|
||||
s.fbos = s.fbos[:idx]
|
||||
}
|
||||
|
||||
func (s *stenciler) release() {
|
||||
s.fbos.delete(s.ctx, 0)
|
||||
s.ctx.DeleteTexture(s.areaLUT)
|
||||
s.ctx.DeleteProgram(s.prog)
|
||||
s.ctx.DeleteBuffer(s.indexBuf)
|
||||
}
|
||||
|
||||
func (p *pather) release() {
|
||||
p.stenciler.release()
|
||||
p.coverer.release()
|
||||
}
|
||||
|
||||
func (c *coverer) release() {
|
||||
for _, p := range c.prog {
|
||||
c.ctx.DeleteProgram(p)
|
||||
}
|
||||
}
|
||||
|
||||
func buildPath(ctx *gl.Functions, p *path.Path) *pathData {
|
||||
buf := ctx.CreateBuffer()
|
||||
ctx.BindBuffer(gl.ARRAY_BUFFER, buf)
|
||||
ctx.BufferData(gl.ARRAY_BUFFER, gl.BytesView(p.Vertices), gl.STATIC_DRAW)
|
||||
return &pathData{
|
||||
ncurves: len(p.Vertices),
|
||||
data: buf,
|
||||
}
|
||||
}
|
||||
|
||||
func (p *pathData) release(ctx *gl.Functions) {
|
||||
ctx.DeleteBuffer(p.data)
|
||||
}
|
||||
|
||||
func (p *pather) begin(sizes []image.Point) {
|
||||
p.stenciler.begin(sizes)
|
||||
}
|
||||
|
||||
func (p *pather) end() {
|
||||
p.stenciler.end()
|
||||
}
|
||||
|
||||
func (p *pather) stencilPath(bounds image.Rectangle, offset f32.Point, uv image.Point, data *pathData) {
|
||||
p.stenciler.stencilPath(bounds, offset, uv, data)
|
||||
}
|
||||
|
||||
func (s *stenciler) beginIntersect(sizes []image.Point) {
|
||||
s.ctx.ActiveTexture(gl.TEXTURE1)
|
||||
s.ctx.BindTexture(gl.TEXTURE_2D, 0)
|
||||
s.ctx.ActiveTexture(gl.TEXTURE0)
|
||||
s.ctx.BlendFunc(gl.DST_COLOR, gl.ZERO)
|
||||
// 8 bit coverage is enough, but OpenGL ES only supports single channel
|
||||
// floating point formats. Replace with GL_RGB+GL_UNSIGNED_BYTE if
|
||||
// no floating point support is available.
|
||||
s.intersections.resize(s.ctx, sizes, gl.R16F, gl.RED, gl.HALF_FLOAT)
|
||||
s.ctx.ClearColor(1.0, 0.0, 0.0, 0.0)
|
||||
s.ctx.UseProgram(s.iprog)
|
||||
}
|
||||
|
||||
func (s *stenciler) endIntersect() {
|
||||
s.ctx.BindFramebuffer(gl.FRAMEBUFFER, s.defFBO)
|
||||
}
|
||||
|
||||
func (s *stenciler) invalidateFBO() {
|
||||
s.intersections.invalidate(s.ctx)
|
||||
s.fbos.invalidate(s.ctx)
|
||||
s.ctx.BindFramebuffer(gl.FRAMEBUFFER, s.defFBO)
|
||||
}
|
||||
|
||||
func (s *stenciler) cover(idx int) stencilFBO {
|
||||
return s.fbos.fbos[idx]
|
||||
}
|
||||
|
||||
func (s *stenciler) begin(sizes []image.Point) {
|
||||
s.ctx.ActiveTexture(gl.TEXTURE1)
|
||||
s.ctx.BindTexture(gl.TEXTURE_2D, 0)
|
||||
s.ctx.ActiveTexture(gl.TEXTURE0)
|
||||
s.ctx.BlendFunc(gl.ONE, gl.ONE)
|
||||
s.fbos.resize(s.ctx, sizes, gl.R16F, gl.RED, gl.HALF_FLOAT)
|
||||
s.ctx.ClearColor(0.0, 0.0, 0.0, 0.0)
|
||||
s.ctx.BindTexture(gl.TEXTURE_2D, s.areaLUT)
|
||||
s.ctx.UseProgram(s.prog)
|
||||
s.ctx.EnableVertexAttribArray(attribPathCorner)
|
||||
s.ctx.EnableVertexAttribArray(attribPathMaxY)
|
||||
s.ctx.EnableVertexAttribArray(attribPathFrom)
|
||||
s.ctx.EnableVertexAttribArray(attribPathCtrl)
|
||||
s.ctx.EnableVertexAttribArray(attribPathTo)
|
||||
s.ctx.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, s.indexBuf)
|
||||
}
|
||||
|
||||
func (s *stenciler) stencilPath(bounds image.Rectangle, offset f32.Point, uv image.Point, data *pathData) {
|
||||
s.ctx.BindBuffer(gl.ARRAY_BUFFER, data.data)
|
||||
s.ctx.Viewport(uv.X, uv.Y, bounds.Dx(), bounds.Dy())
|
||||
// Transform UI coordinates to OpenGL coordinates.
|
||||
texSize := f32.Point{X: float32(bounds.Dx()), Y: float32(bounds.Dy())}
|
||||
scale := f32.Point{X: 2 / texSize.X, Y: 2 / texSize.Y}
|
||||
orig := f32.Point{X: -1 - float32(bounds.Min.X)*2/texSize.X, Y: -1 - float32(bounds.Min.Y)*2/texSize.Y}
|
||||
s.ctx.Uniform2f(s.uScale, scale.X, scale.Y)
|
||||
s.ctx.Uniform2f(s.uOffset, orig.X, orig.Y)
|
||||
s.ctx.Uniform2f(s.uPathOffset, offset.X, offset.Y)
|
||||
// Draw in batches that fit in uint16 indices.
|
||||
start := 0
|
||||
nquads := data.ncurves / 4
|
||||
for start < nquads {
|
||||
batch := nquads - start
|
||||
if max := int(^uint16(0)) / 6; batch > max {
|
||||
batch = max
|
||||
}
|
||||
// Enlarge VBO if necessary.
|
||||
if batch > s.indexBufQuads {
|
||||
indices := make([]uint16, batch*6)
|
||||
for i := 0; i < batch; i++ {
|
||||
i := uint16(i)
|
||||
indices[i*6+0] = i*4 + 0
|
||||
indices[i*6+1] = i*4 + 1
|
||||
indices[i*6+2] = i*4 + 2
|
||||
indices[i*6+3] = i*4 + 2
|
||||
indices[i*6+4] = i*4 + 1
|
||||
indices[i*6+5] = i*4 + 3
|
||||
}
|
||||
s.ctx.BufferData(gl.ELEMENT_ARRAY_BUFFER, gl.BytesView(indices), gl.STATIC_DRAW)
|
||||
s.indexBufQuads = batch
|
||||
}
|
||||
off := path.VertStride * start * 4
|
||||
s.ctx.VertexAttribPointer(attribPathCorner, 2, gl.SHORT, false, path.VertStride, off+int(unsafe.Offsetof((*(*path.Vertex)(nil)).CornerX)))
|
||||
s.ctx.VertexAttribPointer(attribPathMaxY, 1, gl.FLOAT, false, path.VertStride, off+int(unsafe.Offsetof((*(*path.Vertex)(nil)).MaxY)))
|
||||
s.ctx.VertexAttribPointer(attribPathFrom, 2, gl.FLOAT, false, path.VertStride, off+int(unsafe.Offsetof((*(*path.Vertex)(nil)).FromX)))
|
||||
s.ctx.VertexAttribPointer(attribPathCtrl, 2, gl.FLOAT, false, path.VertStride, off+int(unsafe.Offsetof((*(*path.Vertex)(nil)).CtrlX)))
|
||||
s.ctx.VertexAttribPointer(attribPathTo, 2, gl.FLOAT, false, path.VertStride, off+int(unsafe.Offsetof((*(*path.Vertex)(nil)).ToX)))
|
||||
s.ctx.DrawElements(gl.TRIANGLES, batch*6, gl.UNSIGNED_SHORT, 0)
|
||||
start += batch
|
||||
}
|
||||
}
|
||||
|
||||
func (s *stenciler) end() {
|
||||
s.ctx.DisableVertexAttribArray(attribPathCorner)
|
||||
s.ctx.DisableVertexAttribArray(attribPathMaxY)
|
||||
s.ctx.DisableVertexAttribArray(attribPathFrom)
|
||||
s.ctx.DisableVertexAttribArray(attribPathCtrl)
|
||||
s.ctx.DisableVertexAttribArray(attribPathTo)
|
||||
s.ctx.BindFramebuffer(gl.FRAMEBUFFER, s.defFBO)
|
||||
}
|
||||
|
||||
func (p *pather) cover(z float32, mat materialType, col [4]float32, scale, off, uvScale, uvOff, coverScale, coverOff f32.Point) {
|
||||
p.coverer.cover(z, mat, col, scale, off, uvScale, uvOff, coverScale, coverOff)
|
||||
}
|
||||
|
||||
func (c *coverer) cover(z float32, mat materialType, col [4]float32, scale, off, uvScale, uvOff, coverScale, coverOff f32.Point) {
|
||||
c.ctx.UseProgram(c.prog[mat])
|
||||
switch mat {
|
||||
case materialColor:
|
||||
c.ctx.Uniform4f(c.vars[mat].uColor, col[0], col[1], col[2], col[3])
|
||||
case materialTexture:
|
||||
c.ctx.Uniform2f(c.vars[mat].uUVScale, uvScale.X, uvScale.Y)
|
||||
c.ctx.Uniform2f(c.vars[mat].uUVOffset, uvOff.X, uvOff.Y)
|
||||
}
|
||||
c.ctx.Uniform1f(c.vars[mat].z, z)
|
||||
c.ctx.Uniform2f(c.vars[mat].uScale, scale.X, scale.Y)
|
||||
c.ctx.Uniform2f(c.vars[mat].uOffset, off.X, off.Y)
|
||||
c.ctx.Uniform2f(c.vars[mat].uCoverUVScale, coverScale.X, coverScale.Y)
|
||||
c.ctx.Uniform2f(c.vars[mat].uCoverUVOffset, coverOff.X, coverOff.Y)
|
||||
c.ctx.DrawArrays(gl.TRIANGLE_STRIP, 0, 4)
|
||||
}
|
||||
|
||||
func loadLUT(ctx *gl.Functions, lut *image.Gray) (gl.Texture, error) {
|
||||
tex := ctx.CreateTexture()
|
||||
ctx.BindTexture(gl.TEXTURE_2D, tex)
|
||||
ctx.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
|
||||
ctx.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
|
||||
ctx.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
|
||||
ctx.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
|
||||
ctx.PixelStorei(gl.UNPACK_ALIGNMENT, 1)
|
||||
if lut.Stride != lut.Bounds().Dx() {
|
||||
panic("unsupported LUT stride")
|
||||
}
|
||||
ver, _ := gl.ParseGLVersion(ctx.GetString(gl.VERSION))
|
||||
intf, f := gl.R8, gl.RED
|
||||
if ver[0] < 3 {
|
||||
// R8, RED not supported on OpenGL ES 2.0.
|
||||
intf, f = gl.LUMINANCE, gl.LUMINANCE
|
||||
}
|
||||
ctx.TexImage2D(gl.TEXTURE_2D, 0, intf, lut.Bounds().Dx(), lut.Bounds().Dy(), gl.Enum(f), gl.UNSIGNED_BYTE, lut.Pix)
|
||||
ctx.PixelStorei(gl.UNPACK_ALIGNMENT, 4)
|
||||
return tex, nil
|
||||
}
|
||||
|
||||
const stencilVSrc = `
|
||||
#version 100
|
||||
|
||||
precision highp float;
|
||||
|
||||
uniform vec2 scale;
|
||||
uniform vec2 offset;
|
||||
uniform vec2 pathOffset;
|
||||
|
||||
attribute vec2 corner;
|
||||
attribute float maxy;
|
||||
attribute vec2 from;
|
||||
attribute vec2 ctrl;
|
||||
attribute vec2 to;
|
||||
|
||||
varying vec2 vFrom;
|
||||
varying vec2 vCtrl;
|
||||
varying vec2 vTo;
|
||||
|
||||
void main() {
|
||||
// Add a one pixel overlap so curve quads cover their
|
||||
// entire curves. Could use conservative rasterization
|
||||
// if available.
|
||||
vec2 from = from + pathOffset;
|
||||
vec2 ctrl = ctrl + pathOffset;
|
||||
vec2 to = to + pathOffset;
|
||||
float maxy = maxy + pathOffset.y;
|
||||
vec2 pos;
|
||||
if (corner.x > 0.0) {
|
||||
// East.
|
||||
pos.x = max(max(from.x, ctrl.x), to.x)+1.0;
|
||||
} else {
|
||||
// West.
|
||||
pos.x = min(min(from.x, ctrl.x), to.x)-1.0;
|
||||
}
|
||||
if (corner.y > 0.0) {
|
||||
// North.
|
||||
pos.y = maxy + 1.0;
|
||||
} else {
|
||||
// South.
|
||||
pos.y = min(min(from.y, ctrl.y), to.y) - 1.0;
|
||||
}
|
||||
vFrom = from-pos;
|
||||
vCtrl = ctrl-pos;
|
||||
vTo = to-pos;
|
||||
pos *= scale;
|
||||
pos += offset;
|
||||
gl_Position = vec4(pos, 1, 1);
|
||||
}
|
||||
`
|
||||
|
||||
const stencilFSrc = `
|
||||
#version 100
|
||||
|
||||
precision mediump float;
|
||||
|
||||
varying vec2 vFrom;
|
||||
varying vec2 vCtrl;
|
||||
varying vec2 vTo;
|
||||
|
||||
uniform sampler2D areaLUT;
|
||||
|
||||
void main() {
|
||||
float dx = vTo.x - vFrom.x;
|
||||
// Sort from and to in increasing order so the root below
|
||||
// is always the positive square root, if any.
|
||||
// We need the direction of the curve below, so this can't be
|
||||
// done from the vertex shader.
|
||||
bool increasing = vTo.x >= vFrom.x;
|
||||
vec2 left = increasing ? vFrom : vTo;
|
||||
vec2 right = increasing ? vTo : vFrom;
|
||||
|
||||
// The signed horizontal extent of the fragment.
|
||||
vec2 extent = clamp(vec2(vFrom.x, vTo.x), -0.5, 0.5);
|
||||
// Find the t where the curve crosses the middle of the
|
||||
// extent, x₀.
|
||||
// Given the bezier curve with x coordinates P₀, P₁, P₂
|
||||
// where P₀ is at the origin, its x coordinate in t
|
||||
// is given by:
|
||||
//
|
||||
// x(t) = 2(1-t)tP₁ + t²P₂
|
||||
//
|
||||
// Rearranging:
|
||||
//
|
||||
// x(t) = (P₂ - 2P₁)t² + 2P₁t
|
||||
//
|
||||
// Setting x(t) = x₀ and using Muller's quadratic formula ("Citardauq")
|
||||
// for robustnesss,
|
||||
//
|
||||
// t = 2x₀/(2P₁±√(4P₁²+4(P₂-2P₁)x₀))
|
||||
//
|
||||
// which simplifies to
|
||||
//
|
||||
// t = x₀/(P₁±√(P₁²+(P₂-2P₁)x₀))
|
||||
//
|
||||
// Setting v = P₂-P₁,
|
||||
//
|
||||
// t = x₀/(P₁±√(P₁²+(v-P₁)x₀))
|
||||
//
|
||||
// t lie in [0; 1]; P₂ ≥ P₁ and P₁ ≥ 0 since we split curves where
|
||||
// the control point lies before the start point or after the end point.
|
||||
// It can then be shown that only the positive square root is valid.
|
||||
float midx = mix(extent.x, extent.y, 0.5);
|
||||
float x0 = midx - left.x;
|
||||
vec2 p1 = vCtrl - left;
|
||||
vec2 v = right - vCtrl;
|
||||
float t = x0/(p1.x+sqrt(p1.x*p1.x+(v.x-p1.x)*x0));
|
||||
// Find y(t) on the curve.
|
||||
float y = mix(mix(left.y, vCtrl.y, t), mix(vCtrl.y, right.y, t), t);
|
||||
// And the slope.
|
||||
vec2 d_half = mix(p1, v, t);
|
||||
float dy = d_half.y/d_half.x;
|
||||
// Together, y and dy form a line approximation. The areaLUT table
|
||||
// maps the line to a pixel coverage.
|
||||
float width = extent.y - extent.x;
|
||||
// The first axis maps y in [-8;+8] to [0;1].
|
||||
float areau = y/16.0 + 0.5;
|
||||
// The second axis maps slopes in [0;16] to [0;1]. The area is symmetric
|
||||
// around dy = 0. Scale slope with extent width.
|
||||
float areav = abs(dy*width)/16.0;
|
||||
// Look up coverage from y and slope and scale to extent.
|
||||
gl_FragColor.r = texture2D(areaLUT, vec2(areau, areav)).r*width;
|
||||
}
|
||||
`
|
||||
|
||||
const coverVSrc = `
|
||||
#version 100
|
||||
|
||||
precision highp float;
|
||||
|
||||
uniform float z;
|
||||
uniform vec2 scale;
|
||||
uniform vec2 offset;
|
||||
uniform vec2 uvScale;
|
||||
uniform vec2 uvOffset;
|
||||
uniform vec2 uvCoverScale;
|
||||
uniform vec2 uvCoverOffset;
|
||||
|
||||
attribute vec2 pos;
|
||||
|
||||
varying vec2 vCoverUV;
|
||||
|
||||
attribute vec2 uv;
|
||||
varying vec2 vUV;
|
||||
|
||||
void main() {
|
||||
gl_Position = vec4(pos*scale + offset, z, 1);
|
||||
vUV = uv*uvScale + uvOffset;
|
||||
vCoverUV = uv*uvCoverScale+uvCoverOffset;
|
||||
}
|
||||
`
|
||||
|
||||
const coverFSrc = `
|
||||
#version 100
|
||||
|
||||
precision mediump float;
|
||||
|
||||
// Use high precision to be pixel accurate for
|
||||
// large cover atlases.
|
||||
varying highp vec2 vCoverUV;
|
||||
uniform sampler2D cover;
|
||||
varying vec2 vUV;
|
||||
|
||||
HEADER
|
||||
|
||||
void main() {
|
||||
gl_FragColor = GET_COLOR;
|
||||
float cover = abs(texture2D(cover, vCoverUV).r);
|
||||
gl_FragColor *= cover;
|
||||
}
|
||||
`
|
||||
|
||||
const intersectVSrc = `
|
||||
#version 100
|
||||
|
||||
precision highp float;
|
||||
|
||||
attribute vec2 pos;
|
||||
attribute vec2 uv;
|
||||
|
||||
uniform vec2 uvScale;
|
||||
uniform vec2 uvOffset;
|
||||
|
||||
varying vec2 vUV;
|
||||
|
||||
void main() {
|
||||
vec2 p = pos;
|
||||
p.y = -p.y;
|
||||
gl_Position = vec4(p, 0, 1);
|
||||
vUV = uv*uvScale + uvOffset;
|
||||
}
|
||||
`
|
||||
|
||||
const intersectFSrc = `
|
||||
#version 100
|
||||
|
||||
precision mediump float;
|
||||
|
||||
// Use high precision to be pixel accurate for
|
||||
// large cover atlases.
|
||||
varying highp vec2 vUV;
|
||||
uniform sampler2D cover;
|
||||
|
||||
void main() {
|
||||
float cover = abs(texture2D(cover, vUV).r);
|
||||
gl_FragColor.r = cover;
|
||||
}
|
||||
`
|
||||
@@ -0,0 +1,93 @@
|
||||
// SPDX-License-Identifier: Unlicense OR MIT
|
||||
|
||||
package gpu
|
||||
|
||||
import (
|
||||
"time"
|
||||
|
||||
"gioui.org/ui/app/internal/gl"
|
||||
)
|
||||
|
||||
type timers struct {
|
||||
ctx *gl.Functions
|
||||
timers []*timer
|
||||
}
|
||||
|
||||
type timer struct {
|
||||
Elapsed time.Duration
|
||||
ctx *gl.Functions
|
||||
obj gl.Query
|
||||
state timerState
|
||||
}
|
||||
|
||||
type timerState uint8
|
||||
|
||||
const (
|
||||
timerIdle timerState = iota
|
||||
timerRunning
|
||||
timerWaiting
|
||||
)
|
||||
|
||||
func newTimers(ctx *gl.Functions, exts string) *timers {
|
||||
return &timers{
|
||||
ctx: ctx,
|
||||
}
|
||||
}
|
||||
|
||||
func (t *timers) newTimer() *timer {
|
||||
if t == nil {
|
||||
return nil
|
||||
}
|
||||
tt := &timer{
|
||||
ctx: t.ctx,
|
||||
obj: t.ctx.CreateQuery(),
|
||||
}
|
||||
t.timers = append(t.timers, tt)
|
||||
return tt
|
||||
}
|
||||
|
||||
func (t *timer) begin() {
|
||||
if t == nil || t.state != timerIdle {
|
||||
return
|
||||
}
|
||||
t.ctx.BeginQuery(gl.TIME_ELAPSED_EXT, t.obj)
|
||||
t.state = timerRunning
|
||||
}
|
||||
|
||||
func (t *timer) end() {
|
||||
if t == nil || t.state != timerRunning {
|
||||
return
|
||||
}
|
||||
t.ctx.EndQuery(gl.TIME_ELAPSED_EXT)
|
||||
t.state = timerWaiting
|
||||
}
|
||||
|
||||
func (t *timers) ready() bool {
|
||||
if t == nil {
|
||||
return false
|
||||
}
|
||||
for _, tt := range t.timers {
|
||||
if tt.state != timerWaiting {
|
||||
return false
|
||||
}
|
||||
if t.ctx.GetQueryObjectuiv(tt.obj, gl.QUERY_RESULT_AVAILABLE) == 0 {
|
||||
return false
|
||||
}
|
||||
}
|
||||
for _, tt := range t.timers {
|
||||
tt.state = timerIdle
|
||||
nanos := t.ctx.GetQueryObjectuiv(tt.obj, gl.QUERY_RESULT)
|
||||
tt.Elapsed = time.Duration(nanos)
|
||||
}
|
||||
return t.ctx.GetInteger(gl.GPU_DISJOINT_EXT) == 0
|
||||
}
|
||||
|
||||
func (t *timers) release() {
|
||||
if t == nil {
|
||||
return
|
||||
}
|
||||
for _, tt := range t.timers {
|
||||
t.ctx.DeleteQuery(tt.obj)
|
||||
}
|
||||
t.timers = nil
|
||||
}
|
||||
Reference in New Issue
Block a user