# vk_resources.ludic — render3d's Vulkan resources on their own: textures uploaded the way the
# renderer uploads them and read back, a mip chain, the samplers the renderer asks for, and a
# buffer filled and grown. Run it under the validation layer on each machine.
#
# gpu_vk_res.ludic speaks OpenGL's names for formats and filters, as gpu.ludic does, and those
# names only exist where Gl.* is named - hence the one Gl.pixel_scale() below. Nothing here
# opens an OpenGL context or draws with one.
#   bin/ludicc examples/rendering/vk_resources.ludic --headless -o build/vk_resources
import "../../packages/ludic.render3d/gpu_vk.ludic"
import "../../packages/ludic.render3d/gpu_vk_res.ludic"

program VkResources {
  property Marker { on: int = 1 }
  model Anchor { Marker }

  var failures: int = 0
  function check(what: string, ok: bool) -> void {
    if ok { print(`vulkan: {what} ok`) } else { print(`vulkan: {what} FAILED`);  failures += 1 }
  }

  handler Boot phase Start {
    spawn Anchor {}
    print(`vulkan: OpenGL names spliced (pixel scale {Gl.pixel_scale()})`)
    if not gvk_init() { print(`VKRES NONE: {gvk_why}`);  quit() }

    # RGBA8 up and back, byte for byte
    let w = 64
    let h = 32
    let px = bytes(w * h * 4)
    for i in 0 .. w * h { px[i * 4] = i & 255;  px[i * 4 + 1] = (i >> 8) & 255;  px[i * 4 + 2] = (i * 7) & 255;  px[i * 4 + 3] = 200 }
    let t1 = gvk_tex_new()
    check("RGBA8 storage with mips", gvk_tex_storage(t1, false, GL_RGBA8, w, h, 1, true))
    check("RGBA8 upload", gvk_tex_upload(t1, GL_RGBA8, w, h, 1, GL_RGBA, GL_UNSIGNED_BYTE, px))
    check("RGBA8 mip chain (7 levels)", gvk_tex_levels[t1] == 7 and gvk_tex_mips(t1, w, h))
    let back = bytes(w * h * 4)
    check("RGBA8 read-back call", gvk_tex_read(t1, GL_RGBA8, w, h, GL_RGBA, GL_UNSIGNED_BYTE, back))
    var same = true
    for i in 0 .. w * h * 4 { if back[i] != px[i] { same = false } }
    check("RGBA8 read-back matches", same)

    # R32F, the terrain's height field path
    let hf = bytes(w * h * 4)
    for i in 0 .. w * h { Vk.put_i32(hf, i * 4, 0x40000000 + i) }
    let t2 = gvk_tex_new()
    check("R32F target", gvk_tex_storage(t2, false, GL_R32F, w, h, 1, false))
    check("R32F upload", gvk_tex_upload(t2, GL_R32F, w, h, 1, GL_RED, GL_FLOAT, hf))
    let hb = bytes(w * h * 4)
    check("R32F read-back call", gvk_tex_read(t2, GL_R32F, w, h, GL_RED, GL_FLOAT, hb))
    var hsame = true
    for i in 0 .. w * h * 4 { if hb[i] != hf[i] { hsame = false } }
    check("R32F read-back matches", hsame)

    # RGB8 stored as RGBA, and an HDR image's float RGB into half floats
    let rgb = bytes(w * h * 3)
    for i in 0 .. w * h * 3 { rgb[i] = (i * 3) & 255 }
    let t3 = gvk_tex_new()
    check("SRGB8 expanded to RGBA", gvk_tex_storage(t3, false, GL_SRGB8, w, h, 1, true) and gvk_tex_upload(t3, GL_SRGB8, w, h, 1, GL_RGB, GL_UNSIGNED_BYTE, rgb))
    let fl = bytes(w * h * 12)
    for i in 0 .. w * h * 3 { Vk.put_i32(fl, i * 4, 0x3FC00000) }
    let t4 = gvk_tex_new()
    check("RGB16F from floats (halved)", gvk_tex_storage(t4, false, GL_RGB16F, w, h, 1, true) and gvk_tex_upload(t4, GL_RGB16F, w, h, 1, GL_RGB, GL_FLOAT, fl))
    check("half of 1.5 is 0x3E00", gvk_half(0x3FC00000) == 0x3E00)

    # a 16-bit RGB PNG (a normal map): big-endian samples, swapped on upload, alpha filled opaque
    let n16 = bytes(w * h * 6)
    for i in 0 .. w * h * 3 { n16[i * 2] = (i >> 8) & 255;  n16[i * 2 + 1] = i & 255 }
    let t7 = gvk_tex_new()
    gvk_unpack_swap = true
    check("RGB16 swapped upload", gvk_tex_storage(t7, false, GL_RGB16, w, h, 1, true) and gvk_tex_upload(t7, GL_RGB16, w, h, 1, GL_RGB, GL_UNSIGNED_SHORT, n16))
    gvk_unpack_swap = false
    let b16 = bytes(w * h * 6)
    check("RGB16 read-back call", gvk_tex_read(t7, GL_RGB16, w, h, GL_RGB, GL_UNSIGNED_SHORT, b16))
    var s16 = true
    for i in 0 .. w * h * 3 { if b16[i * 2] != (i & 255) or b16[i * 2 + 1] != ((i >> 8) & 255) { s16 = false } }
    check("RGB16 samples arrive little-endian", s16)

    # the shadow cascades: a depth array, and a render-sized half-float target with no pixels
    let t5 = gvk_tex_new()
    check("D32 array of 4", gvk_tex_storage(t5, true, GL_DEPTH_COMPONENT32F, 256, 256, 4, false))
    let t6 = gvk_tex_new()
    check("RGBA16F target", gvk_tex_storage(t6, false, GL_RGBA16F, 320, 180, 1, false))

    # the samplers the renderer asks for, and that asking twice returns the same one
    let s1 = gvk_sampler(GL_LINEAR_MIPMAP_LINEAR, GL_LINEAR, GL_REPEAT, GL_REPEAT, 0, 0x41800000)
    let s2 = gvk_sampler(GL_LINEAR, GL_LINEAR, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE, 0, 0)
    let s3 = gvk_sampler(GL_LINEAR, GL_LINEAR, GL_CLAMP_TO_BORDER, GL_CLAMP_TO_BORDER, GL_LEQUAL, 0)
    let s4 = gvk_sampler(GL_NEAREST, GL_NEAREST, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE, 0, 0)
    let again = gvk_sampler(GL_LINEAR_MIPMAP_LINEAR, GL_LINEAR, GL_REPEAT, GL_REPEAT, 0, 0x41800000)
    check("four samplers made", s1 != 0 and s2 != 0 and s3 != 0 and s4 != 0 and len(gvk_smp) == 4)
    check("a sampler asked for twice is one sampler", again == s1)

    # a buffer filled, filled again smaller (kept), then larger (grown)
    let b = gvk_buf_new()
    let data = bytes(4096)
    for i in 0 .. 4096 { data[i] = i & 255 }
    check("buffer upload", gvk_buf_upload(b, 1024, data))
    let first = gvk_buf[b]
    check("a smaller upload keeps the buffer", gvk_buf_upload(b, 512, data) and gvk_buf[b] == first)
    check("a larger upload grows it", gvk_buf_upload(b, 4096, data) and gvk_buf_size[b] >= 4096)

    for t in 1 .. 8 { gvk_tex_release(t) }
    gvk_buf_release(b)
    for i in 0 .. len(gvk_smp) { Vk.destroy_sampler(gvk_dev, gvk_smp[i], null) }
    print(`vulkan: {gvk_n_allocs} allocations left after freeing`)
    check("every allocation freed", gvk_n_allocs == 0)
    gvk_shutdown()
    if failures == 0 { print("VKRES OK") } else { print(`VKRES FAILED ({failures})`) }
    quit()
  }
}