OGL Shader Working

shader.h

static const char* vertex_shader_src =
        R"(
    #version 440

    layout(location = 0) uniform mat4 proj;
    layout(location = 0) in vec2 position;
    layout(location = 1) in vec2 uv;
    layout(location = 2) in vec4 color;

    layout(location = 0) out VertexData {
        vec2 uv;
        vec4 color;
    } out_data;

    void main() {
        out_data.uv = uv;
        out_data.color = color;
        gl_Position = proj * vec4(position, 0.0, 1.0);
    }
)";

static const char* fragment_shader_src =
        R"(
    #version 440

    layout(binding = 0) uniform sampler2D tex;
    layout(location = 0) in VertexData {
        vec2 uv;
        vec4 color;
    } vertex_data;

    out vec4 color;

    void main() {
        color = vertex_data.color * texture(tex, vertex_data.uv);
    }
)";