#version 450

layout(location = 0) in vec2 inPosition;
layout(location = 1) in vec4 inColor;
layout(location = 2) in vec2 inTexCoord;

layout(location = 0) out vec4 fragColor;
layout(location = 1) out vec2 fragTexCoord;

layout(binding = 0) uniform UniformBufferObject {
    float time;
    vec2 resolution;
    float rotation;
    float wavePhase;
} ubo;

void main() {
    // Transform position from pixel coordinates to normalized device coordinates
    vec2 pos = inPosition;

    // Convert to NDC: (0, 0) to (width, height) -> (-1, -1) to (1, 1)
    vec2 ndc = (pos / ubo.resolution) * 2.0 - 1.0;

    // Flip Y axis (Vulkan has Y down, we want Y up for easier math)
    ndc.y = -ndc.y;

    gl_Position = vec4(ndc, 0.0, 1.0);
    fragColor = inColor;
    fragTexCoord = inTexCoord;
}