func (c *glContext) stroke(call *glCall) {
paths := c.paths[call.pathOffset : call.pathOffset+call.pathCount]
if c.flags&StencilStrokes != 0 {
gl.Enable(gl.STENCIL_TEST)
c.setStencilMask(0xff)
// Fill the stroke base without overlap
c.setStencilFunc(gl.EQUAL, 0x00, 0xff)
gl.StencilOp(gl.KEEP, gl.KEEP, gl.INCR)
c.setUniforms(call.uniformOffset+1, call.image)
checkError(c, "stroke fill 0")
for i := range paths {
path := &paths[i]
gl.DrawArrays(gl.TRIANGLE_STRIP, path.strokeOffset, path.strokeCount)
}
// Draw anti-aliased pixels.
c.setUniforms(call.uniformOffset, call.image)
c.setStencilFunc(gl.EQUAL, 0x00, 0xff)
gl.StencilOp(gl.KEEP, gl.KEEP, gl.KEEP)
for i := range paths {
path := &paths[i]
gl.DrawArrays(gl.TRIANGLE_STRIP, path.strokeOffset, path.strokeCount)
}
// Clear stencil buffer.
gl.ColorMask(false, false, false, false)
c.setStencilFunc(gl.ALWAYS, 0x00, 0xff)
gl.StencilOp(gl.ZERO, gl.ZERO, gl.ZERO)
checkError(c, "stroke fill 1")
for i := range paths {
path := &paths[i]
gl.DrawArrays(gl.TRIANGLE_STRIP, path.strokeOffset, path.strokeCount)
}
gl.ColorMask(true, true, true, true)
gl.Disable(gl.STENCIL_TEST)
} else {
c.setUniforms(call.uniformOffset, call.image)
checkError(c, "stroke fill")
for i := range paths {
path := &paths[i]
gl.DrawArrays(gl.TRIANGLE_STRIP, path.strokeOffset, path.strokeCount)
}
}
}
func (c *glContext) fill(call *glCall) {
pathSentinel := call.pathOffset + call.pathCount
// Draw shapes
gl.Enable(gl.STENCIL_TEST)
c.setStencilMask(0xff)
c.setStencilFunc(gl.ALWAYS, 0x00, 0xff)
gl.ColorMask(false, false, false, false)
// set bindpoint for solid loc
c.setUniforms(call.uniformOffset, 0)
checkError(c, "fill simple")
gl.StencilOpSeparate(gl.FRONT, gl.KEEP, gl.KEEP, gl.INCR_WRAP)
gl.StencilOpSeparate(gl.BACK, gl.KEEP, gl.KEEP, gl.DECR_WRAP)
gl.Disable(gl.CULL_FACE)
for i := call.pathOffset; i < pathSentinel; i++ {
path := &c.paths[i]
gl.DrawArrays(gl.TRIANGLE_FAN, path.fillOffset, path.fillCount)
}
gl.Enable(gl.CULL_FACE)
// Draw anti-aliased pixels
gl.ColorMask(true, true, true, true)
c.setUniforms(call.uniformOffset+1, call.image)
if c.flags&AntiAlias != 0 {
c.setStencilFunc(gl.EQUAL, 0x00, 0xff)
gl.StencilOp(gl.KEEP, gl.KEEP, gl.KEEP)
// Draw fringes
for i := call.pathOffset; i < pathSentinel; i++ {
path := &c.paths[i]
gl.DrawArrays(gl.TRIANGLE_STRIP, path.strokeOffset, path.strokeCount)
}
}
// Draw fill
c.setStencilFunc(gl.NOTEQUAL, 0x00, 0xff)
gl.StencilOp(gl.ZERO, gl.ZERO, gl.ZERO)
gl.DrawArrays(gl.TRIANGLES, call.triangleOffset, call.triangleCount)
gl.Disable(gl.STENCIL_TEST)
}
func (p *glParams) renderFlush() {
c := p.context
if len(c.calls) > 0 {
gl.UseProgram(c.shader.program)
gl.BlendFunc(gl.ONE, gl.ONE_MINUS_SRC_ALPHA)
gl.Enable(gl.CULL_FACE)
gl.CullFace(gl.BACK)
gl.FrontFace(gl.CCW)
gl.Enable(gl.BLEND)
gl.Disable(gl.DEPTH_TEST)
gl.Disable(gl.SCISSOR_TEST)
gl.ColorMask(true, true, true, true)
gl.StencilMask(0xffffffff)
gl.StencilOp(gl.KEEP, gl.KEEP, gl.KEEP)
gl.StencilFunc(gl.ALWAYS, 0, 0xffffffff)
gl.ActiveTexture(gl.TEXTURE0)
gl.BindTexture(gl.TEXTURE_2D, gl.Texture{})
c.stencilMask = 0xffffffff
c.stencilFunc = gl.ALWAYS
c.stencilFuncRef = 0
c.stencilFuncMask = 0xffffffff
b := castFloat32ToByte(c.vertexes)
//dumpLog("vertex:", c.vertexes)
// Upload vertex data
gl.BindBuffer(gl.ARRAY_BUFFER, c.vertexBuffer)
gl.BufferData(gl.ARRAY_BUFFER, b, gl.STREAM_DRAW)
gl.EnableVertexAttribArray(c.shader.vertexAttrib)
gl.EnableVertexAttribArray(c.shader.tcoordAttrib)
gl.VertexAttribPointer(c.shader.vertexAttrib, 2, gl.FLOAT, false, 4*4, 0)
gl.VertexAttribPointer(c.shader.tcoordAttrib, 2, gl.FLOAT, false, 4*4, 8)
// Set view and texture just once per frame.
gl.Uniform1i(c.shader.locations[glnvgLocTEX], 0)
gl.Uniform2fv(c.shader.locations[glnvgLocVIEWSIZE], c.view[:])
for i := range c.calls {
call := &c.calls[i]
switch call.callType {
case glnvgFILL:
c.fill(call)
case glnvgCONVEXFILL:
c.convexFill(call)
case glnvgSTROKE:
c.stroke(call)
case glnvgTRIANGLES:
c.triangles(call)
}
}
gl.DisableVertexAttribArray(c.shader.vertexAttrib)
gl.DisableVertexAttribArray(c.shader.tcoordAttrib)
gl.Disable(gl.CULL_FACE)
gl.BindBuffer(gl.ARRAY_BUFFER, gl.Buffer{})
gl.UseProgram(gl.Program{})
c.bindTexture(nil)
}
c.vertexes = c.vertexes[:0]
c.paths = c.paths[:0]
c.calls = c.calls[:0]
c.uniforms = c.uniforms[:0]
}