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go-opengl-pixel
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remove support for indices in vertex array

This commit is contained in:
faiface 2016-12-31 02:48:43 +01:00
parent db0d646ca8
commit 69032cdcf3
1 changed files with 8 additions and 57 deletions
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59
pixelgl/vertex.go
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@ -12,8 +12,8 @@ import (
// VertexArray is an OpenGL vertex array object that also holds it's own vertex buffer object.
// From the user's points of view, VertexArray is an array of vertices that can be drawn.
type VertexArray struct {
vao, vbo, ebo binder
numVertices, numIndices int
vao, vbo binder
numVertices int
format AttrFormat
stride int
offset map[string]int
@ -22,9 +22,8 @@ type VertexArray struct {
// NewVertexArray creates a new empty vertex array.
//
// You cannot specify vertex attributes in this constructor, only their count. Use
// SetVertexAttribute* methods to set the vertex attributes. Use indices to specify how you
// want to combine vertices into triangles.
func NewVertexArray(shader *Shader, numVertices int, indices []int) (*VertexArray, error) {
// SetVertexAttribute* methods to set the vertex attributes.
func NewVertexArray(shader *Shader, numVertices int) (*VertexArray, error) {
va := &VertexArray{
vao: binder{
restoreLoc: gl.VERTEX_ARRAY_BINDING,
@ -38,12 +37,6 @@ func NewVertexArray(shader *Shader, numVertices int, indices []int) (*VertexArra
gl.BindBuffer(gl.ARRAY_BUFFER, obj)
},
},
ebo: binder{
restoreLoc: gl.ELEMENT_ARRAY_BUFFER_BINDING,
bindFunc: func(obj uint32) {
gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, obj)
},
},
numVertices: numVertices,
format: shader.VertexFormat(),
stride: shader.VertexFormat().Size(),
@ -71,9 +64,6 @@ func NewVertexArray(shader *Shader, numVertices int, indices []int) (*VertexArra
emptyData := make([]byte, numVertices*va.stride)
gl.BufferData(gl.ARRAY_BUFFER, len(emptyData), gl.Ptr(emptyData), gl.DYNAMIC_DRAW)
gl.GenBuffers(1, &va.ebo.obj)
defer va.ebo.bind().restore()
for name, typ := range va.format {
loc := gl.GetAttribLocation(shader.ID(), gl.Str(name+"\x00"))
@ -102,8 +92,6 @@ func NewVertexArray(shader *Shader, numVertices int, indices []int) (*VertexArra
va.vao.restore()
va.SetIndices(indices)
runtime.SetFinalizer(va, (*VertexArray).delete)
return va, nil
@ -113,7 +101,6 @@ func (va *VertexArray) delete() {
DoNoBlock(func() {
gl.DeleteVertexArrays(1, &va.vao.obj)
gl.DeleteBuffers(1, &va.vbo.obj)
gl.DeleteBuffers(1, &va.ebo.obj)
})
}
@ -138,41 +125,7 @@ func (va *VertexArray) VertexFormat() AttrFormat {
//
// The vertex array must be bound before calling this method.
func (va *VertexArray) Draw() {
gl.DrawElements(gl.TRIANGLES, int32(va.numIndices), gl.UNSIGNED_INT, gl.PtrOffset(0))
}
// SetIndices sets the indices of triangles to be drawn. Triangles will be formed from the
// vertices of the array as defined by these indices. The first drawn triangle is specified by
// the first three indices, the second by the fourth through sixth and so on.
//
// The vertex array must be bound before calling this method.
func (va *VertexArray) SetIndices(indices []int) {
if len(indices)%3 != 0 {
panic("vertex array set indices: number of indices not divisible by 3")
}
indices32 := make([]uint32, len(indices))
for i := range indices32 {
indices32[i] = uint32(indices[i])
}
va.numIndices = len(indices32)
gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, 4*len(indices32), gl.Ptr(indices32), gl.DYNAMIC_DRAW)
}
// Indices returns the current indices of triangles to be drawn.
//
// The vertex array must be bound before calling this method.
func (va *VertexArray) Indices() []int {
indices32 := make([]uint32, va.numIndices)
gl.GetBufferSubData(gl.ELEMENT_ARRAY_BUFFER, 0, 4*len(indices32), gl.Ptr(indices32))
indices := make([]int, len(indices32))
for i := range indices {
indices[i] = int(indices32[i])
}
return indices
gl.DrawArrays(gl.TRIANGLES, 0, int32(va.numVertices))
}
// SetVertexAttr sets the value of the specified vertex attribute of the specified vertex.
@ -433,12 +386,10 @@ func (va *VertexArray) Vertices() (vertices []map[Attr]interface{}) {
func (va *VertexArray) Begin() {
va.vao.bind()
va.vbo.bind()
va.ebo.bind()
}
// End unbinds a vertex array and restores the previous one.
func (va *VertexArray) End() {
va.ebo.restore()
va.vbo.restore()
va.vao.restore()
}