func SetUniformF(shader, variable string, f float32) error {
prog, ok := shader_progs[shader]
if !ok {
return fmt.Errorf("Tried to set a uniform in an unknown shader '%s'", shader)
}
bvariable := []byte(fmt.Sprintf("%s\x00", variable))
loc := gl.GetUniformLocation(prog, (*int8)(unsafe.Pointer(&bvariable[0])))
gl.Uniform1f(loc, f)
return nil
}
// RenderString must be called on the render thread. x and y are the initial position of the pen,
// in screen coordinates, and height is the height of a full line of text, in screen coordinates.
func (d *Dictionary) RenderString(str string, x, y, height float64) {
if str == "" {
return
}
// No synchronization necessary because everything is run serially on the render thread anyway.
if d.strs == nil {
d.strs = make(map[string]strData)
}
data, ok := d.strs[str]
if !ok {
data = d.bindString(str)
d.strs[str] = data
}
render.EnableShader("glop.font")
defer render.EnableShader("")
gl.ActiveTexture(gl.TEXTURE0)
gl.BindTexture(gl.TEXTURE_2D, d.atlas.texture)
location, _ := render.GetUniformLocation("glop.font", "tex")
gl.Uniform1i(location, 0)
gl.BindSampler(0, d.atlas.sampler)
location, _ = render.GetUniformLocation("glop.font", "height")
gl.Uniform1f(location, float32(height))
var viewport [4]int32
gl.GetIntegerv(gl.VIEWPORT, &viewport[0])
location, _ = render.GetUniformLocation("glop.font", "screen")
gl.Uniform2f(location, float32(viewport[2]), float32(viewport[3]))
location, _ = render.GetUniformLocation("glop.font", "pen")
gl.Uniform2f(location, float32(x)+float32(viewport[0]), float32(y)+float32(viewport[1]))
location, _ = render.GetUniformLocation("glop.font", "textColor")
gl.Uniform3f(location, d.color[0], d.color[1], d.color[2])
gl.Enable(gl.BLEND)
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
gl.BindVertexArray(data.varrays[0])
gl.DrawArrays(gl.TRIANGLES, 0, data.count)
}