foreign_system_library "opengl32.lib" when ODIN_OS == "windows";
import . "windows.odin";


CONTEXT_MAJOR_VERSION_ARB             :: 0x2091;
CONTEXT_MINOR_VERSION_ARB             :: 0x2092;
CONTEXT_FLAGS_ARB                     :: 0x2094;
CONTEXT_PROFILE_MASK_ARB              :: 0x9126;
CONTEXT_FORWARD_COMPATIBLE_BIT_ARB    :: 0x0002;
CONTEXT_CORE_PROFILE_BIT_ARB          :: 0x00000001;
CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB :: 0x00000002;

Hglrc    :: Handle;
ColorRef :: u32;

LayerPlaneDescriptor :: struct {
	size:             u16;
	version:          u16;
	flags:            u32;
	pixel_type:       u8;
	color_bits:       u8;
	red_bits:         u8;
	red_shift:        u8;
	green_bits:       u8;
	green_shift:      u8;
	blue_bits:        u8;
	blue_shift:       u8;
	alpha_bits:       u8;
	alpha_shift:      u8;
	accum_bits:       u8;
	accum_red_bits:   u8;
	accum_green_bits: u8;
	accum_blue_bits:  u8;
	accum_alpha_bits: u8;
	depth_bits:       u8;
	stencil_bits:     u8;
	aux_buffers:      u8;
	layer_type:       u8;
	reserved:         u8;
	transparent:      ColorRef;
}

PointFloat :: struct {x, y: f32};

Glyph_MetricsFloat :: struct {
	black_box_x:  f32;
	black_box_y:  f32;
	glyph_origin: PointFloat;
	cell_inc_x:   f32;
	cell_inc_y:   f32;
}

CreateContextAttribsARBType :: proc(hdc: Hdc, h_share_context: rawptr, attribList: ^i32) -> Hglrc;
ChoosePixelFormatARBType    :: proc(hdc: Hdc, attrib_i_list: ^i32, attrib_f_list: ^f32, max_formats: u32, formats: ^i32, num_formats : ^u32) -> Bool #cc_c;
SwapIntervalEXTType         :: proc(interval: i32) -> bool #cc_c;
GetExtensionsStringARBType  :: proc(Hdc) -> ^u8 #cc_c;

// Procedures
	create_context_attribs_arb: CreateContextAttribsARBType;
	choose_pixel_format_arb:    ChoosePixelFormatARBType;
	swap_interval_ext:          SwapIntervalEXTType;
	get_extensions_string_arb:  GetExtensionsStringARBType;



foreign opengl32 {
	create_context            :: proc(hdc: Hdc) -> Hglrc                                                                                                 #link_name "wglCreateContext"          ---;
	make_current              :: proc(hdc: Hdc, hglrc: Hglrc) -> Bool                                                                                    #link_name "wglMakeCurrent"            ---;
	get_proc_address          :: proc(c_str: ^u8) -> rawptr                                                                                              #link_name "wglGetProcAddress"         ---;
	delete_context            :: proc(hglrc: Hglrc) -> Bool                                                                                              #link_name "wglDeleteContext"          ---;
	copy_context              :: proc(src, dst: Hglrc, mask: u32) -> Bool                                                                                #link_name "wglCopyContext"            ---;
	create_layer_context      :: proc(hdc: Hdc, layer_plane: i32) -> Hglrc                                                                               #link_name "wglCreateLayerContext"     ---;
	describe_layer_plane      :: proc(hdc: Hdc, pixel_format, layer_plane: i32, bytes: u32, pd: ^LayerPlaneDescriptor) -> Bool                           #link_name "wglDescribeLayerPlane"     ---;
	get_current_context       :: proc() -> Hglrc                                                                                                         #link_name "wglGetCurrentContext"      ---;
	get_current_dc            :: proc() -> Hdc                                                                                                           #link_name "wglGetCurrentDC"           ---;
	get_layer_palette_entries :: proc(hdc: Hdc, layer_plane, start, entries: i32, cr: ^ColorRef) -> i32                                                  #link_name "wglGetLayerPaletteEntries" ---;
	realize_layer_palette     :: proc(hdc: Hdc, layer_plane: i32, realize: Bool) -> Bool                                                                 #link_name "wglRealizeLayerPalette"    ---;
	set_layer_palette_entries :: proc(hdc: Hdc, layer_plane, start, entries: i32, cr: ^ColorRef) -> i32                                                  #link_name "wglSetLayerPaletteEntries" ---;
	share_lists               :: proc(hglrc1, hglrc2: Hglrc) -> Bool                                                                                     #link_name "wglShareLists"             ---;
	swap_layer_buffers        :: proc(hdc: Hdc, planes: u32) -> Bool                                                                                     #link_name "wglSwapLayerBuffers"       ---;
	use_font_bitmaps          :: proc(hdc: Hdc, first, count, list_base: u32) -> Bool                                                                    #link_name "wglUseFontBitmaps"         ---;
	use_font_outlines         :: proc(hdc: Hdc, first, count, list_base: u32, deviation, extrusion: f32, format: i32, gmf: ^Glyph_MetricsFloat) -> Bool  #link_name "wglUseFontOutlines"        ---;
}