/*
 * Tuxánci 2 - A first person shooter
 * Copyright (C) 2025-2026  Connor Thomson
 *
 * 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/>.
 */

struct TextUniforms {
    float4 clip_rect;
};

[[vk::binding(0, 1)]]
ConstantBuffer<TextUniforms> uniforms : register(b0, space1);

struct VSOutput {
    float4 position : SV_Position;
    float2 uv       : TEXCOORD0;
};

VSOutput main(uint vertexID : SV_VertexID) {
    static const float2 positions[6] = {
        float2(0.0, 0.0),
        float2(1.0, 0.0),
        float2(0.0, 1.0),
        float2(0.0, 1.0),
        float2(1.0, 0.0),
        float2(1.0, 1.0)
    };

    float2 position = positions[vertexID];
    float2 clip = lerp(uniforms.clip_rect.xy, uniforms.clip_rect.zw, position);

    VSOutput output;
    output.position = float4(clip, 0.0, 1.0);
    output.uv = position;
    return output;
}