rework VertexSlice for better performance

graphics.go

@@ -25,13 +25,14 @@ func (td *TrianglesData) Draw() {
 
 func (td *TrianglesData) resize(len int) {
 	if len > td.Len() {
-		newData := make(TrianglesData, len-td.Len())
+		needAppend := len - td.Len()
-		// default values
+		for i := 0; i < needAppend; i++ {
-		for i := range newData {
+			*td = append(*td, struct {
-			newData[i].Color = NRGBA{1, 1, 1, 1}
+				Position Vec
-			newData[i].Texture = V(-1, -1)
+				Color    NRGBA
+				Texture  Vec
+			}{V(0, 0), NRGBA{1, 1, 1, 1}, V(-1, -1)})
 		}
-		*td = append(*td, newData...)
 	}
 	if len < td.Len() {
 		*td = (*td)[:len]

pixelgl/attr.go

@@ -3,29 +3,14 @@ package pixelgl
 // AttrFormat defines names and types of OpenGL attributes (vertex format, uniform format, etc.).
 //
 // Example:
-//   AttrFormat{"position": Vec2, "color": Vec4, "texCoord": Vec2}
+//   AttrFormat{{"position", Vec2}, {"color", Vec4}, {"texCoord": Vec2}}
-type AttrFormat map[string]AttrType
+type AttrFormat []Attr
-
-// Contains checks whether a format contains a specific attribute.
-//
-// It does a little more than a hard check: e.g. if you query a Vec2 attribute, but the format
-// contains Vec3, Contains returns true, because Vec2 is assignable to Vec3. Specifically,
-// Float -> Vec2 -> Vec3 -> Vec4 (transitively).  This however does not work for matrices or ints.
-func (af AttrFormat) Contains(attr Attr) bool {
-	if typ, ok := af[attr.Name]; ok {
-		if (Float <= typ && typ <= Vec4) && (Float <= attr.Type && attr.Type <= typ) {
-			return true
-		}
-		return attr.Type == typ
-	}
-	return false
-}
 
 // Size returns the total size of all attributes of an attribute format.
 func (af AttrFormat) Size() int {
 	total := 0
-	for _, typ := range af {
+	for _, attr := range af {
-		total += typ.Size()
+		total += attr.Type.Size()
 	}
 	return total
 }

pixelgl/shader.go

@@ -13,7 +13,7 @@ type Shader struct {
 	program    binder
 	vertexFmt  AttrFormat
 	uniformFmt AttrFormat
-	uniforms   map[string]int32
+	uniformLoc []int32
 }
 
 // NewShader creates a new shader program from the specified vertex shader and fragment shader
@@ -31,7 +31,7 @@ func NewShader(vertexFmt, uniformFmt AttrFormat, vertexShader, fragmentShader st
 		},
 		vertexFmt:  vertexFmt,
 		uniformFmt: uniformFmt,
-		uniforms:   make(map[string]int32),
+		uniformLoc: make([]int32, len(uniformFmt)),
 	}
 
 	var vshader, fshader uint32
@@ -99,9 +99,9 @@ func NewShader(vertexFmt, uniformFmt AttrFormat, vertexShader, fragmentShader st
 	}
 
 	// uniforms
-	for name := range uniformFmt {
+	for i, uniform := range uniformFmt {
-		loc := gl.GetUniformLocation(shader.program.obj, gl.Str(name+"\x00"))
+		loc := gl.GetUniformLocation(shader.program.obj, gl.Str(uniform.Name+"\x00"))
-		shader.uniforms[name] = loc
+		shader.uniformLoc[i] = loc
 	}
 
 	runtime.SetFinalizer(shader, (*Shader).delete)
@@ -125,9 +125,10 @@ func (s *Shader) UniformFormat() AttrFormat {
 	return s.uniformFmt
 }
 
-// SetUniformAttr sets the value of a uniform attribute of a shader.
+// SetUniformAttr sets the value of a uniform attribute of a shader. The attribute is
+// specified by the index in the Shader's uniform format.
 //
-// If the attribute does not exist, this method returns false.
+// If the uniform attribute does not exist in the Shader, this method returns false.
 //
 // Supplied value must correspond to the type of the attribute. Correct types are these
 // (right-hand is the type of the value):
@@ -148,54 +149,54 @@ func (s *Shader) UniformFormat() AttrFormat {
 // No other types are supported.
 //
 // The shader must be bound before calling this method.
-func (s *Shader) SetUniformAttr(attr Attr, value interface{}) (ok bool) {
+func (s *Shader) SetUniformAttr(uniform int, value interface{}) (ok bool) {
-	if !s.uniformFmt.Contains(attr) {
+	if s.uniformLoc[uniform] < 0 {
 		return false
 	}
 
-	switch attr.Type {
+	switch s.uniformFmt[uniform].Type {
 	case Int:
 		value := value.(int32)
-		gl.Uniform1iv(s.uniforms[attr.Name], 1, &value)
+		gl.Uniform1iv(s.uniformLoc[uniform], 1, &value)
 	case Float:
 		value := value.(float32)
-		gl.Uniform1fv(s.uniforms[attr.Name], 1, &value)
+		gl.Uniform1fv(s.uniformLoc[uniform], 1, &value)
 	case Vec2:
 		value := value.(mgl32.Vec2)
-		gl.Uniform2fv(s.uniforms[attr.Name], 1, &value[0])
+		gl.Uniform2fv(s.uniformLoc[uniform], 1, &value[0])
 	case Vec3:
 		value := value.(mgl32.Vec3)
-		gl.Uniform3fv(s.uniforms[attr.Name], 1, &value[0])
+		gl.Uniform3fv(s.uniformLoc[uniform], 1, &value[0])
 	case Vec4:
 		value := value.(mgl32.Vec4)
-		gl.Uniform4fv(s.uniforms[attr.Name], 1, &value[0])
+		gl.Uniform4fv(s.uniformLoc[uniform], 1, &value[0])
 	case Mat2:
 		value := value.(mgl32.Mat2)
-		gl.UniformMatrix2fv(s.uniforms[attr.Name], 1, false, &value[0])
+		gl.UniformMatrix2fv(s.uniformLoc[uniform], 1, false, &value[0])
 	case Mat23:
 		value := value.(mgl32.Mat2x3)
-		gl.UniformMatrix2x3fv(s.uniforms[attr.Name], 1, false, &value[0])
+		gl.UniformMatrix2x3fv(s.uniformLoc[uniform], 1, false, &value[0])
 	case Mat24:
 		value := value.(mgl32.Mat2x4)
-		gl.UniformMatrix2x4fv(s.uniforms[attr.Name], 1, false, &value[0])
+		gl.UniformMatrix2x4fv(s.uniformLoc[uniform], 1, false, &value[0])
 	case Mat3:
 		value := value.(mgl32.Mat3)
-		gl.UniformMatrix3fv(s.uniforms[attr.Name], 1, false, &value[0])
+		gl.UniformMatrix3fv(s.uniformLoc[uniform], 1, false, &value[0])
 	case Mat32:
 		value := value.(mgl32.Mat3x2)
-		gl.UniformMatrix3x2fv(s.uniforms[attr.Name], 1, false, &value[0])
+		gl.UniformMatrix3x2fv(s.uniformLoc[uniform], 1, false, &value[0])
 	case Mat34:
 		value := value.(mgl32.Mat3x4)
-		gl.UniformMatrix3x4fv(s.uniforms[attr.Name], 1, false, &value[0])
+		gl.UniformMatrix3x4fv(s.uniformLoc[uniform], 1, false, &value[0])
 	case Mat4:
 		value := value.(mgl32.Mat4)
-		gl.UniformMatrix4fv(s.uniforms[attr.Name], 1, false, &value[0])
+		gl.UniformMatrix4fv(s.uniformLoc[uniform], 1, false, &value[0])
 	case Mat42:
 		value := value.(mgl32.Mat4x2)
-		gl.UniformMatrix4x2fv(s.uniforms[attr.Name], 1, false, &value[0])
+		gl.UniformMatrix4x2fv(s.uniformLoc[uniform], 1, false, &value[0])
 	case Mat43:
 		value := value.(mgl32.Mat4x3)
-		gl.UniformMatrix4x3fv(s.uniforms[attr.Name], 1, false, &value[0])
+		gl.UniformMatrix4x3fv(s.uniformLoc[uniform], 1, false, &value[0])
 	default:
 		panic("set uniform attr: invalid attribute type")
 	}

pixelgl/vertex.go

@@ -1,22 +1,13 @@
 package pixelgl
 
 import (
+	"fmt"
 	"runtime"
 
 	"github.com/go-gl/gl/v3.3-core/gl"
-	"github.com/go-gl/mathgl/mgl32"
 	"github.com/pkg/errors"
 )
 
-// VertexData holds data of one vertex stored in vertex attributes. The values must match attribute
-// types precisely. Here's the table of correct types (no other types are valid):
-//
-//   Attr{Type: Float}: float32
-//   Attr{Type: Vec2}:  mgl32.Vec2
-//   Attr{Type: Vec3}:  mgl32.Vec3
-//   Attr{Type: Vec4}:  mgl32.Vec4
-type VertexData map[Attr]interface{}
-
 // VertexSlice points to a portion of (or possibly whole) vertex array. It is used as a pointer,
 // contrary to Go's builtin slices. This is, so that append can be 'in-place'. That's for the good,
 // because Begin/End-ing a VertexSlice would become super confusing, if append returned a new
@@ -53,6 +44,11 @@ func (vs *VertexSlice) VertexFormat() AttrFormat {
 	return vs.va.format
 }
 
+// Stride returns the number of float32 elements occupied by one vertex.
+func (vs *VertexSlice) Stride() int {
+	return vs.va.stride / 4
+}
+
 // Len returns the length of the VertexSlice.
 func (vs *VertexSlice) Len() int {
 	return vs.j - vs.i
@@ -117,26 +113,36 @@ func (vs VertexSlice) grow(len int) VertexSlice {
 // is not sufficient, a new, larger underlying vertex array will be allocated. The content of the
 // original VertexSlice will be copied to the new underlying vertex array.
 //
+// The data is in the same format as with SetVertexData.
+//
 // The VertexSlice is appended 'in-place', contrary Go's builtin slices.
-func (vs *VertexSlice) Append(vertices ...VertexData) {
+func (vs *VertexSlice) Append(data []float32) {
 	vs.End() // vs must have been Begin-ed before calling this method
-	*vs = vs.grow(vs.Len() + len(vertices))
+	*vs = vs.grow(vs.Len() + len(data)/vs.Stride())
 	vs.Begin()
-	vs.Slice(vs.Len()-len(vertices), vs.Len()).SetVertexData(vertices)
+	vs.Slice(vs.Len()-len(data)/vs.Stride(), vs.Len()).SetVertexData(data)
 }
 
 // SetVertexData sets the contents of the VertexSlice.
 //
+// The data is a slice of float32's, where each vertex attribute occupies a certain number of
+// elements. Namely, Float occupies 1, Vec2 occupies 2, Vec3 occupies 3 and Vec4 occupies 4. The
+// attribues in the data slice must be in the same order as in the vertex format of this Vertex
+// Slice.
+//
 // If the length of vertices does not match the length of the VertexSlice, this methdo panics.
-func (vs *VertexSlice) SetVertexData(vertices []VertexData) {
+func (vs *VertexSlice) SetVertexData(data []float32) {
-	if len(vertices) != vs.Len() {
+	if len(data)/vs.Stride() != vs.Len() {
+		fmt.Println(len(data)/vs.Stride(), vs.Len())
 		panic("set vertex data: wrong length of vertices")
 	}
-	vs.va.setVertexData(vs.i, vs.j, vertices)
+	vs.va.setVertexData(vs.i, vs.j, data)
 }
 
 // VertexData returns the contents of the VertexSlice.
-func (vs *VertexSlice) VertexData() []VertexData {
+//
+// The data is in the same format as with SetVertexData.
+func (vs *VertexSlice) VertexData() []float32 {
 	return vs.va.vertexData(vs.i, vs.j)
 }
 
@@ -160,7 +166,7 @@ type vertexArray struct {
 	cap      int
 	format   AttrFormat
 	stride   int
-	offset   map[string]int
+	offset   []int
 	shader   *Shader
 }
 
@@ -187,19 +193,19 @@ func newVertexArray(shader *Shader, cap int) *vertexArray {
 		cap:    cap,
 		format: shader.VertexFormat(),
 		stride: shader.VertexFormat().Size(),
-		offset: make(map[string]int),
+		offset: make([]int, len(shader.VertexFormat())),
 		shader: shader,
 	}
 
 	offset := 0
-	for name, typ := range va.format {
+	for i, attr := range va.format {
-		switch typ {
+		switch attr.Type {
 		case Float, Vec2, Vec3, Vec4:
 		default:
 			panic(errors.New("failed to create vertex array: invalid attribute type"))
 		}
-		va.offset[name] = offset
+		va.offset[i] = offset
-		offset += typ.Size()
+		offset += attr.Type.Size()
 	}
 
 	gl.GenVertexArrays(1, &va.vao.obj)
@@ -212,11 +218,11 @@ func newVertexArray(shader *Shader, cap int) *vertexArray {
 	emptyData := make([]byte, cap*va.stride)
 	gl.BufferData(gl.ARRAY_BUFFER, len(emptyData), gl.Ptr(emptyData), gl.DYNAMIC_DRAW)
 
-	for name, typ := range va.format {
+	for i, attr := range va.format {
-		loc := gl.GetAttribLocation(shader.program.obj, gl.Str(name+"\x00"))
+		loc := gl.GetAttribLocation(shader.program.obj, gl.Str(attr.Name+"\x00"))
 
 		var size int32
-		switch typ {
+		switch attr.Type {
 		case Float:
 			size = 1
 		case Vec2:
@@ -233,7 +239,7 @@ func newVertexArray(shader *Shader, cap int) *vertexArray {
 			gl.FLOAT,
 			false,
 			int32(va.stride),
-			gl.PtrOffset(va.offset[name]),
+			gl.PtrOffset(va.offset[i]),
 		)
 		gl.EnableVertexAttribArray(uint32(loc))
 	}
@@ -266,82 +272,20 @@ func (va *vertexArray) draw(i, j int) {
 	gl.DrawArrays(gl.TRIANGLES, int32(i), int32(i+j))
 }
 
-func (va *vertexArray) setVertexData(i, j int, vertices []VertexData) {
+func (va *vertexArray) setVertexData(i, j int, data []float32) {
 	if j-i == 0 {
 		// avoid setting 0 bytes of buffer data
 		return
 	}
-
-	data := make([]float32, (j-i)*va.stride/4)
-
-	for vertex := i; vertex < j; vertex++ {
-		for attr, value := range vertices[vertex] {
-			if !va.format.Contains(attr) {
-				continue
-			}
-
-			offset := va.stride*vertex + va.offset[attr.Name]
-
-			switch attr.Type {
-			case Float:
-				data[offset/4] = value.(float32)
-			case Vec2:
-				value := value.(mgl32.Vec2)
-				copy(data[offset/4:offset/4+attr.Type.Size()/4], value[:])
-			case Vec3:
-				value := value.(mgl32.Vec3)
-				copy(data[offset/4:offset/4+attr.Type.Size()/4], value[:])
-			case Vec4:
-				value := value.(mgl32.Vec4)
-				copy(data[offset/4:offset/4+attr.Type.Size()/4], value[:])
-			default:
-				panic("set vertex: invalid attribute type")
-			}
-		}
-	}
-
 	gl.BufferSubData(gl.ARRAY_BUFFER, i*va.stride, len(data)*4, gl.Ptr(data))
 }
 
-func (va *vertexArray) vertexData(i, j int) []VertexData {
+func (va *vertexArray) vertexData(i, j int) []float32 {
 	if j-i == 0 {
 		// avoid getting 0 bytes of buffer data
 		return nil
 	}
-
 	data := make([]float32, (j-i)*va.stride/4)
-
 	gl.GetBufferSubData(gl.ARRAY_BUFFER, i*va.stride, len(data)*4, gl.Ptr(data))
-
+	return data
-	vertices := make([]VertexData, 0, (j - i))
-
-	for vertex := i; vertex < j; vertex++ {
-		values := make(map[Attr]interface{})
-
-		for name, typ := range va.format {
-			attr := Attr{name, typ}
-			offset := va.stride*vertex + va.offset[attr.Name]
-
-			switch attr.Type {
-			case Float:
-				values[attr] = data[offset/4]
-			case Vec2:
-				var value mgl32.Vec2
-				copy(value[:], data[offset/4:offset/4+attr.Type.Size()/4])
-				values[attr] = value
-			case Vec3:
-				var value mgl32.Vec3
-				copy(value[:], data[offset/4:offset/4+attr.Type.Size()/4])
-				values[attr] = value
-			case Vec4:
-				var value mgl32.Vec4
-				copy(value[:], data[offset/4:offset/4+attr.Type.Size()/4])
-				values[attr] = value
-			}
-		}
-
-		vertices = append(vertices, values)
-	}
-
-	return vertices
 }

window.go

@@ -363,11 +363,11 @@ func (w *Window) end() {
 type windowTriangles struct {
 	w    *Window
 	vs   *pixelgl.VertexSlice
-	data []pixelgl.VertexData
+	data []float32
 }
 
 func (wt *windowTriangles) Len() int {
-	return len(wt.data)
+	return len(wt.data) / wt.vs.Stride()
 }
 
 func (wt *windowTriangles) Draw() {
@@ -397,15 +397,14 @@ func (wt *windowTriangles) Draw() {
 
 func (wt *windowTriangles) resize(len int) {
 	if len > wt.Len() {
-		newData := make([]pixelgl.VertexData, len-wt.Len())
+		needAppend := len - wt.Len()
-		// default values
+		for i := 0; i < needAppend; i++ {
-		for i := range newData {
+			wt.data = append(wt.data,
-			newData[i] = pixelgl.VertexData{
+				0, 0,
-				colorVec4:   mgl32.Vec4{1, 1, 1, 1},
+				1, 1, 1, 1,
-				textureVec2: mgl32.Vec2{-1, -1},
+				-1, -1,
-			}
+			)
 		}
-		wt.data = append(wt.data, newData...)
 	}
 	if len < wt.Len() {
 		wt.data = wt.data[:len]
@@ -416,30 +415,24 @@ func (wt *windowTriangles) updateData(offset int, t Triangles) {
 	if t, ok := t.(TrianglesPosition); ok {
 		for i := offset; i < offset+t.Len(); i++ {
 			px, py := t.Position(i).XY()
-			wt.data[i][positionVec2] = mgl32.Vec2{
+			wt.data[i*wt.vs.Stride()+0] = float32(px)
-				float32(px),
+			wt.data[i*wt.vs.Stride()+1] = float32(py)
-				float32(py),
-			}
 		}
 	}
 	if t, ok := t.(TrianglesColor); ok {
 		for i := offset; i < offset+t.Len(); i++ {
 			col := t.Color(i)
-			wt.data[i][colorVec4] = mgl32.Vec4{
+			wt.data[i*wt.vs.Stride()+2] = float32(col.R)
-				float32(col.R),
+			wt.data[i*wt.vs.Stride()+3] = float32(col.G)
-				float32(col.G),
+			wt.data[i*wt.vs.Stride()+4] = float32(col.B)
-				float32(col.B),
+			wt.data[i*wt.vs.Stride()+5] = float32(col.A)
-				float32(col.A),
-			}
 		}
 	}
 	if t, ok := t.(TrianglesTexture); ok {
 		for i := offset; i < offset+t.Len(); i++ {
 			tx, ty := t.Texture(i).XY()
-			wt.data[i][textureVec2] = mgl32.Vec2{
+			wt.data[i*wt.vs.Stride()+6] = float32(tx)
-				float32(tx),
+			wt.data[i*wt.vs.Stride()+7] = float32(ty)
-				float32(ty),
-			}
 		}
 	}
 }
@@ -448,11 +441,12 @@ func (wt *windowTriangles) submitData() {
 	data := wt.data // avoid race condition
 	pixelgl.DoNoBlock(func() {
 		wt.vs.Begin()
-		if len(wt.data) > wt.vs.Len() {
+		dataLen := len(data) / wt.vs.Stride()
-			wt.vs.Append(make([]pixelgl.VertexData, len(data)-wt.vs.Len())...)
+		if dataLen > wt.vs.Len() {
+			wt.vs.Append(make([]float32, (dataLen-wt.vs.Len())*wt.vs.Stride()))
 		}
-		if len(wt.data) < wt.vs.Len() {
+		if dataLen < wt.vs.Len() {
-			wt.vs = wt.vs.Slice(0, len(wt.data))
+			wt.vs = wt.vs.Slice(0, dataLen)
 		}
 		wt.vs.SetVertexData(wt.data)
 		wt.vs.End()
@@ -481,23 +475,28 @@ func (wt *windowTriangles) Copy() Triangles {
 }
 
 func (wt *windowTriangles) Position(i int) Vec {
-	v := wt.data[i][positionVec2].(mgl32.Vec2)
+	px := wt.data[i*wt.vs.Stride()+0]
-	return V(float64(v.X()), float64(v.Y()))
+	py := wt.data[i*wt.vs.Stride()+1]
+	return V(float64(px), float64(py))
 }
 
 func (wt *windowTriangles) Color(i int) NRGBA {
-	c := wt.data[i][colorVec4].(mgl32.Vec4)
+	r := wt.data[i*wt.vs.Stride()+2]
+	g := wt.data[i*wt.vs.Stride()+3]
+	b := wt.data[i*wt.vs.Stride()+4]
+	a := wt.data[i*wt.vs.Stride()+5]
 	return NRGBA{
-		R: float64(c.X()),
+		R: float64(r),
-		G: float64(c.Y()),
+		G: float64(g),
-		B: float64(c.Z()),
+		B: float64(b),
-		A: float64(c.W()),
+		A: float64(a),
 	}
 }
 
 func (wt *windowTriangles) Texture(i int) Vec {
-	t := wt.data[i][textureVec2].(mgl32.Vec2)
+	tx := wt.data[i*wt.vs.Stride()+6]
-	return V(float64(t.X()), float64(t.Y()))
+	ty := wt.data[i*wt.vs.Stride()+7]
+	return V(float64(tx), float64(ty))
 }
 
 // MakeTriangles generates a specialized copy of the supplied triangles that will draw onto this
@@ -538,15 +537,26 @@ func (w *Window) SetMaskColor(c color.Color) {
 	w.col = mgl32.Vec4{r, g, b, a}
 }
 
+const (
+	positionVec2 int = iota
+	colorVec4
+	textureVec2
+)
+
 var defaultVertexFormat = pixelgl.AttrFormat{
-	"position": pixelgl.Vec2,
+	positionVec2: {Name: "position", Type: pixelgl.Vec2},
-	"color":    pixelgl.Vec4,
+	colorVec4:    {Name: "color", Type: pixelgl.Vec4},
-	"texture":  pixelgl.Vec2,
+	textureVec2:  {Name: "texture", Type: pixelgl.Vec2},
 }
 
+const (
+	maskColorVec4 int = iota
+	transformMat3
+)
+
 var defaultUniformFormat = pixelgl.AttrFormat{
-	"maskColor": pixelgl.Vec4,
+	{Name: "maskColor", Type: pixelgl.Vec4},
-	"transform": pixelgl.Mat3,
+	{Name: "transform", Type: pixelgl.Mat3},
 }
 
 var defaultVertexShader = `
@@ -587,26 +597,3 @@ void main() {
 	}
 }
 `
-
-var (
-	positionVec2 = pixelgl.Attr{
-		Name: "position",
-		Type: pixelgl.Vec2,
-	}
-	colorVec4 = pixelgl.Attr{
-		Name: "color",
-		Type: pixelgl.Vec4,
-	}
-	textureVec2 = pixelgl.Attr{
-		Name: "texture",
-		Type: pixelgl.Vec2,
-	}
-	maskColorVec4 = pixelgl.Attr{
-		Name: "maskColor",
-		Type: pixelgl.Vec4,
-	}
-	transformMat3 = pixelgl.Attr{
-		Name: "transform",
-		Type: pixelgl.Mat3,
-	}
-)