func (lr *LinesRenderer) Draw(line *LineGeometry, mv mgl32.Mat4, style *LineStyle) (err error) {
var (
dataBytes int = len(line.Vertices) * int(lr.stride)
indexBytes int = len(line.Indices) * int(lr.stride)
elementCount int32 = int32(len(line.Indices))
r, g, b, a = style.Color.RGBA()
)
gl.Uniform1f(lr.thicknessLoc, style.Thickness)
gl.Uniform1f(lr.innerLoc, style.Inner)
gl.Uniform4f(lr.colorLoc, float32(r)/255.0, float32(g)/255.0, float32(b)/255.0, float32(a)/255.0)
gl.UniformMatrix4fv(lr.modelviewLoc, 1, false, &mv[0])
if dataBytes > lr.bufferBytes {
lr.bufferBytes = dataBytes
gl.BufferData(gl.ARRAY_BUFFER, dataBytes, gl.Ptr(line.Vertices), gl.STREAM_DRAW)
gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, indexBytes, gl.Ptr(line.Indices), gl.STREAM_DRAW)
} else {
gl.BufferSubData(gl.ARRAY_BUFFER, 0, dataBytes, gl.Ptr(line.Vertices))
gl.BufferSubData(gl.ELEMENT_ARRAY_BUFFER, 0, indexBytes, gl.Ptr(line.Indices))
}
gl.DrawElements(gl.TRIANGLES, elementCount, gl.UNSIGNED_INT, gl.PtrOffset(0))
if e := gl.GetError(); e != 0 {
err = fmt.Errorf("ERROR: OpenGL error %X", e)
}
return
}
func (b *GLBuffer) Upload(data interface{}, size int) {
b.Bind()
if size > b.bufferBytes {
b.bufferBytes = size
gl.BufferData(b.target, size, gl.Ptr(data), gl.STREAM_DRAW)
} else {
gl.BufferSubData(b.target, 0, size, gl.Ptr(data))
}
}
func (r *Framerate) Render(camera *core.Camera) (err error) {
r.data.Sample()
var (
modelView = mgl32.Ident4()
dataBytes int = int(r.data.Count) * int(r.stride)
)
gl.Uniform4f(r.locColor, 255.0/255.0, 0, 0, 255.0/255.0)
gl.UniformMatrix4fv(r.locModelView, 1, false, &modelView[0])
gl.UniformMatrix4fv(r.locProjection, 1, false, &camera.Projection[0])
if dataBytes > r.vboBytes {
r.vboBytes = dataBytes
gl.BufferData(gl.ARRAY_BUFFER, dataBytes, gl.Ptr(r.data.Points), gl.STREAM_DRAW)
} else {
gl.BufferSubData(gl.ARRAY_BUFFER, 0, dataBytes, gl.Ptr(r.data.Points))
}
gl.DrawArrays(gl.POINTS, 0, r.data.Count)
if e := gl.GetError(); e != 0 {
err = fmt.Errorf("ERROR: OpenGL error %X", e)
}
return
}
func (tr *SpriteRenderer) Draw(instances []SpriteConfig) error {
var (
bytesNeeded int
byteoffset int
count int32
data unsafe.Pointer
float float32 = 0
floatSize uint32
i uint32
offset unsafe.Pointer
sprite SpriteConfig
stride int32
)
floatSize = uint32(unsafe.Sizeof(float))
stride = int32(unsafe.Sizeof(sprite))
gl.UseProgram(tr.program)
gl.Uniform1i(tr.textureUnitLoc, 0)
// Instance data binding
gl.BindBuffer(gl.ARRAY_BUFFER, tr.instanceVBO)
count = int32(len(instances))
bytesNeeded = int(stride * count)
data = gl.Ptr(instances)
if bytesNeeded > tr.instanceBytes {
gl.BufferData(gl.ARRAY_BUFFER, bytesNeeded, data, gl.STREAM_DRAW)
tr.instanceBytes = bytesNeeded
} else {
gl.BufferSubData(gl.ARRAY_BUFFER, 0, bytesNeeded, data)
}
gl.EnableVertexAttribArray(tr.translationLoc)
gl.VertexAttribPointer(tr.translationLoc, 3, gl.FLOAT, false, stride, tr.offAttrX)
gl.VertexAttribDivisor(tr.translationLoc, 1)
gl.EnableVertexAttribArray(tr.rotationLoc)
gl.VertexAttribPointer(tr.rotationLoc, 3, gl.FLOAT, false, stride, tr.offAttrRotationX)
gl.VertexAttribDivisor(tr.rotationLoc, 1)
gl.EnableVertexAttribArray(tr.scaleLoc)
gl.VertexAttribPointer(tr.scaleLoc, 3, gl.FLOAT, false, stride, tr.offAttrScaleX)
gl.VertexAttribDivisor(tr.scaleLoc, 1)
gl.EnableVertexAttribArray(tr.colorLoc)
gl.VertexAttribPointer(tr.colorLoc, 4, gl.FLOAT, false, stride, tr.offAttrColor)
gl.VertexAttribDivisor(tr.colorLoc, 1)
for i = 0; i < 4; i++ {
byteoffset = int(i * 4 * floatSize)
offset = gl.PtrOffset(tr.offAttrPointAdj + byteoffset)
gl.EnableVertexAttribArray(tr.pointAdjLoc + i)
gl.VertexAttribPointer(tr.pointAdjLoc+i, 4, gl.FLOAT, false, stride, offset)
gl.VertexAttribDivisor(tr.pointAdjLoc+i, 1)
offset = gl.PtrOffset(tr.offAttrTextureAdj + byteoffset)
gl.EnableVertexAttribArray(tr.textureAdjLoc + i)
gl.VertexAttribPointer(tr.textureAdjLoc+i, 4, gl.FLOAT, false, stride, offset)
gl.VertexAttribDivisor(tr.textureAdjLoc+i, 1)
}
// Projection
gl.UniformMatrix4fv(tr.projectionLoc, 1, false, &tr.Renderer.Camera.Projection[0])
// Actually draw.
gl.DrawArraysInstanced(gl.TRIANGLES, 0, 6, int32(len(instances)))
// Undo instance attr repetition.
gl.VertexAttribDivisor(tr.translationLoc, 0)
gl.VertexAttribDivisor(tr.rotationLoc, 0)
gl.VertexAttribDivisor(tr.scaleLoc, 0)
gl.VertexAttribDivisor(tr.colorLoc, 0)
for i = 0; i < 4; i++ {
gl.VertexAttribDivisor(tr.pointAdjLoc+i, 0)
gl.VertexAttribDivisor(tr.textureAdjLoc+i, 0)
}
gl.BindBuffer(gl.ARRAY_BUFFER, 0)
return nil
}