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) }