; ftpd is a server implementation based on the following:
; - RFC  959 (https://tools.ietf.org/html/rfc959)
; - RFC 3659 (https://tools.ietf.org/html/rfc3659)
; - suggested implementation details from https://cr.yp.to/ftp/filesystem.html
; 
; Copyright (C) 2020 Michael Theall
; 
; This program is free software: you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation, either version 3 of the License, or
; (at your option) any later version.
; 
; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
; GNU General Public License for more details.
; 
; You should have received a copy of the GNU General Public License
; along with this program.  If not, see <https://www.gnu.org/licenses/>.

; ImGui PICA200 vertex shader

; uniforms
; Projection matrix
.fvec proj[4]

; constants
; [1.0, 0.0, 1.0/255.0, 0.0]
.constf constants(1.0, 0.0, 0.00392156862745, 0.0)

; outputs
.out outPos   position
.out outUv    texcoord0
.out outColor color

; inputs (defined as aliases for convenience)
.alias inPos   v0
.alias inUv    v1
.alias inColor v2

.proc main
	; force inPos.z = 0.0, inPos.w = 1.0
	mov r0.xy, inPos.xy
	mov r0.zw, constants.yx

	; outPos = proj * inPos
	dp4 outPos.x, proj[0], r0
	dp4 outPos.y, proj[1], r0
	dp4 outPos.z, proj[2], r0
	dp4 outPos.w, proj[3], r0

	; outUv = inUv
	mov outUv, inUv

	; normalize inColor
	mul r1, constants.zzzz, inColor

	; outColor = inColor
	mov outColor, r1

	; we're finished
	end
.end