func (m Mesh) draw() {
gl.EnableVertexAttribArray(0)
gl.EnableVertexAttribArray(1)
gl.EnableVertexAttribArray(2)
if m.vbo == 0 {
panic("attempt to set array buffer with VBO=0")
}
gl.BindBuffer(gl.ARRAY_BUFFER, m.vbo)
gl.VertexAttribPointer(0, 3, gl.FLOAT, false, VertexSize*4, gl.PtrOffset(0))
gl.VertexAttribPointer(1, 2, gl.FLOAT, false, VertexSize*4, gl.PtrOffset(12))
gl.VertexAttribPointer(2, 3, gl.FLOAT, false, VertexSize*4, gl.PtrOffset(20))
if m.vbo == 0 {
panic("attempt to set element array buffer with VBO=0")
}
gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, m.ibo)
if m.size == 0 {
panic("attempt to draw elements with mesh size = 0")
}
gl.DrawElements(gl.TRIANGLES, m.size, gl.UNSIGNED_INT, gl.PtrOffset(0))
gl.DisableVertexAttribArray(0)
gl.DisableVertexAttribArray(1)
gl.DisableVertexAttribArray(2)
}
func (c *Context) EnableVertexAttribArray(p Program, location string) {
_ = c.runOnContextThread(func() error {
l := c.locationCache.GetAttribLocation(c, p, location)
gl.EnableVertexAttribArray(uint32(l))
return nil
})
}
func (v *Video) initGL() {
if err := gl.Init(); err != nil {
panic(err)
}
gl.Enable(gl.CULL_FACE)
gl.Enable(gl.DEPTH_TEST)
gl.ClearColor(0.0, 0.0, 0.0, 1.0)
v.prog = createProgram(vertShaderSrcDef, fragShaderSrcDef)
posAttrib := uint32(gl.GetAttribLocation(v.prog, gl.Str("vPosition"+"\x00")))
texCoordAttr := uint32(gl.GetAttribLocation(v.prog, gl.Str("vTexCoord"+"\x00")))
v.textureUni = gl.GetAttribLocation(v.prog, gl.Str("texture"+"\x00"))
var texture uint32
gl.GenTextures(1, &texture)
gl.ActiveTexture(gl.TEXTURE0)
gl.BindTexture(gl.TEXTURE_2D, texture)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST)
gl.UseProgram(v.prog)
gl.EnableVertexAttribArray(posAttrib)
gl.EnableVertexAttribArray(texCoordAttr)
//posAttrib.EnableArray()
//texCoordAttr.EnableArray()
var vbo uint32
gl.GenBuffers(1, &vbo)
gl.BindBuffer(gl.ARRAY_BUFFER, vbo)
verts := []float32{-1.0, 1.0, -1.0, -1.0, 1.0, -1.0, 1.0, -1.0, 1.0, 1.0, -1.0, 1.0}
gl.BufferData(gl.ARRAY_BUFFER, len(verts)*int(unsafe.Sizeof(verts[0])), gl.Ptr(verts), gl.STATIC_DRAW)
var textCoorBuf uint32
gl.GenBuffers(1, &textCoorBuf)
gl.BindBuffer(gl.ARRAY_BUFFER, textCoorBuf)
texVerts := []float32{0.0, 1.0, 0.0, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0, 1.0, 0.0, 1.0}
gl.BufferData(gl.ARRAY_BUFFER, len(texVerts)*int(unsafe.Sizeof(texVerts[0])), gl.Ptr(texVerts), gl.STATIC_DRAW)
gl.VertexAttribPointer(posAttrib, 2, gl.FLOAT, false, 0, gl.PtrOffset(0))
gl.VertexAttribPointer(texCoordAttr, 2, gl.FLOAT, false, 0, gl.PtrOffset(0))
//posAttrib.AttribPointer(2, gl.FLOAT, false, 0, uintptr(0))
//texCoordAttr.AttribPointer(2, gl.FLOAT, false, 0, uintptr(0))
}
func onDisplay(program uint32) {
coords := uint32(attributeCoord2d)
vcolor := uint32(attributeVColor)
gl.ClearColor(1.0, 1.0, 1.0, 1.0)
gl.Clear(gl.COLOR_BUFFER_BIT)
gl.UseProgram(program)
gl.Enable(gl.BLEND)
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
gl.Uniform1f(uniformFade, curFade)
gl.EnableVertexAttribArray(coords)
gl.EnableVertexAttribArray(vcolor)
gl.BindBuffer(gl.ARRAY_BUFFER, vboTriangle)
gl.VertexAttribPointer(coords, 2, gl.FLOAT, false, 5*floatSize, nil)
gl.VertexAttribPointer(vcolor, 3, gl.FLOAT, false, 5*floatSize, gl.PtrOffset(2*floatSize))
gl.DrawArrays(gl.TRIANGLES, 0, 3)
gl.DisableVertexAttribArray(vcolor)
gl.DisableVertexAttribArray(coords)
}
func onDisplay(program uint32, coords uint32) {
gl.ClearColor(1.0, 1.0, 1.0, 1.0)
gl.Clear(gl.COLOR_BUFFER_BIT)
gl.UseProgram(program)
gl.EnableVertexAttribArray(coords)
triangleVertices := []float32{
0.0, 0.8,
-0.8, -0.8,
0.8, -0.8}
gl.VertexAttribPointer(coords, 2, gl.FLOAT, false, 0, gl.Ptr(triangleVertices))
gl.DrawArrays(gl.TRIANGLES, 0, 3)
gl.DisableVertexAttribArray(coords)
}
func onDisplay(program uint32, coords uint32) {
gl.ClearColor(1.0, 1.0, 1.0, 1.0)
gl.Clear(gl.COLOR_BUFFER_BIT)
gl.Enable(gl.BLEND)
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
gl.UseProgram(program)
gl.EnableVertexAttribArray(coords)
gl.VertexAttribPointer(coords, 2, gl.FLOAT, false, 0, nil)
gl.DrawArrays(gl.TRIANGLES, 0, 3)
gl.DisableVertexAttribArray(coords)
}
func (vao *VAO) Enable(elements int, buffer *Buffer, attrib Attrib, opts ...VAOOption) {
opt := vaoOption{
stride: 0,
offset: 0,
normalize: false,
}
for _, o := range opts {
o(&opt)
}
gl.BindVertexArray(vao.id)
defer gl.BindVertexArray(0)
gl.BindBuffer(gl.ARRAY_BUFFER, buffer.id)
defer gl.BindBuffer(gl.ARRAY_BUFFER, 0)
gl.EnableVertexAttribArray(attrib.Location())
gl.VertexAttribPointer(
attrib.Location(),
int32(elements),
buffer.data.typ,
opt.normalize,
int32(opt.stride*buffer.data.siz),
gl.PtrOffset(opt.offset*buffer.data.siz))
}
// EnableVertexAttribArray enables a vertex attribute array.
//
// http://www.khronos.org/opengles/sdk/docs/man3/html/glEnableVertexAttribArray.xhtml
func EnableVertexAttribArray(a Attrib) {
gl.EnableVertexAttribArray(uint32(a.Value))
}
func (c *Context) EnableVertexAttribArray(p Program, location string) {
l := GetAttribLocation(c, p, location)
gl.EnableVertexAttribArray(uint32(l))
}
func (c *Context) EnableVertexAttribArray(index int) {
gl.EnableVertexAttribArray(uint32(index))
}
func (*backend) EnableVertexAttribArray(a *gg.Attribute) {
gl.EnableVertexAttribArray(a.Value.(uint32))
}