From c02ad6d7fb3769498fabc9479293b6faea07385f Mon Sep 17 00:00:00 2001
From: Sander Schobers <sander@schobers.eu>
Date: Sat, 28 Dec 2019 01:41:32 +0100
Subject: [PATCH] Added DisplayMode and PixelFormat.

---
 display.go     | 33 +++++++++++++++++++++++++++++++--
 pixelformat.go | 41 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+), 2 deletions(-)
 create mode 100644 pixelformat.go

diff --git a/display.go b/display.go
index 230e424..61925db 100644
--- a/display.go
+++ b/display.go
@@ -5,14 +5,43 @@ import "C"
 
 import (
 	"errors"
+	"sort"
 	"unsafe"
 )
 
-// Display represents a display
+// Display represents a display.
 type Display struct {
 	display *C.ALLEGRO_DISPLAY
 }
 
+// DisplayMode contains information about a fullscreen display mode.
+type DisplayMode struct {
+	Width       int
+	Height      int
+	Format      PixelFormat
+	RefreshRate int
+}
+
+// DisplayMode returns all available fullscreen display modes.
+func DisplayModes() []DisplayMode {
+	n := int(C.al_get_num_display_modes())
+	var modes []DisplayMode
+	var mode C.ALLEGRO_DISPLAY_MODE
+	for i := 0; i < n; i++ {
+		C.al_get_display_mode(C.int(i), &mode)
+		modes = append(modes, DisplayMode{
+			Width:       int(mode.width),
+			Height:      int(mode.height),
+			Format:      PixelFormat(mode.format),
+			RefreshRate: int(mode.refresh_rate),
+		})
+	}
+	weight := func(m DisplayMode) int { return (m.Width*m.Height)*10000 + (m.RefreshRate * 100) + int(m.Format) }
+	sort.Slice(modes, func(i, j int) bool { return weight(modes[i]) < weight(modes[j]) })
+	return modes
+}
+
+// NewDisplayOptions sets options for creating a new display.
 type NewDisplayOptions struct {
 	Fullscreen bool
 	Resizable  bool
@@ -24,7 +53,7 @@ type NewDisplayOptions struct {
 	OpenGL     bool
 }
 
-// NewDisplay creates a display
+// NewDisplay creates a display.
 func NewDisplay(width, height int, options NewDisplayOptions) (*Display, error) {
 	var flags C.int = C.ALLEGRO_WINDOWED
 	if options.Fullscreen {
diff --git a/pixelformat.go b/pixelformat.go
new file mode 100644
index 0000000..70988d8
--- /dev/null
+++ b/pixelformat.go
@@ -0,0 +1,41 @@
+package allg5
+
+// #include <allegro5/allegro.h>
+import "C"
+
+// PixelFormat describes the components a pixel.
+type PixelFormat int
+
+const (
+	PixelFormatAny                PixelFormat = C.ALLEGRO_PIXEL_FORMAT_ANY
+	PixelFormatAnyNoAlpha                     = C.ALLEGRO_PIXEL_FORMAT_ANY_NO_ALPHA
+	PixelFormatAnyAlpha                       = C.ALLEGRO_PIXEL_FORMAT_ANY_WITH_ALPHA
+	PixelFormatAny15NoAlpha                   = C.ALLEGRO_PIXEL_FORMAT_ANY_15_NO_ALPHA
+	PixelFormatAny16NoAlpha                   = C.ALLEGRO_PIXEL_FORMAT_ANY_16_NO_ALPHA
+	PixelFormatAny16Alpha                     = C.ALLEGRO_PIXEL_FORMAT_ANY_16_WITH_ALPHA
+	PixelFormatAny24NoAlpha                   = C.ALLEGRO_PIXEL_FORMAT_ANY_24_NO_ALPHA
+	PixelFormatAny32NoAlpha                   = C.ALLEGRO_PIXEL_FORMAT_ANY_32_NO_ALPHA
+	PixelFormatAny32Alpha                     = C.ALLEGRO_PIXEL_FORMAT_ANY_32_WITH_ALPHA
+	PixelFormatARGB8888                       = C.ALLEGRO_PIXEL_FORMAT_ARGB_8888
+	PixelFormatRGBA8888                       = C.ALLEGRO_PIXEL_FORMAT_RGBA_8888
+	PixelFormatARGB4444                       = C.ALLEGRO_PIXEL_FORMAT_ARGB_4444
+	PixelFormatRGB888                         = C.ALLEGRO_PIXEL_FORMAT_RGB_888
+	PixelFormatRGB565                         = C.ALLEGRO_PIXEL_FORMAT_RGB_565
+	PixelFormatRGB555                         = C.ALLEGRO_PIXEL_FORMAT_RGB_555
+	PixelFormatRGBA5551                       = C.ALLEGRO_PIXEL_FORMAT_RGBA_5551
+	PixelFormatARGB1555                       = C.ALLEGRO_PIXEL_FORMAT_ARGB_1555
+	PixelFormatABGR8888                       = C.ALLEGRO_PIXEL_FORMAT_ABGR_8888
+	PixelFormatXBGR8888                       = C.ALLEGRO_PIXEL_FORMAT_XBGR_8888
+	PixelFormatBGR888                         = C.ALLEGRO_PIXEL_FORMAT_BGR_888
+	PixelFormatBGR565                         = C.ALLEGRO_PIXEL_FORMAT_BGR_565
+	PixelFormatBGR555                         = C.ALLEGRO_PIXEL_FORMAT_BGR_555
+	PixelFormatRGBX8888                       = C.ALLEGRO_PIXEL_FORMAT_RGBX_8888
+	PixelFormatXRGB8888                       = C.ALLEGRO_PIXEL_FORMAT_XRGB_8888
+	PixelFormatABGRF32                        = C.ALLEGRO_PIXEL_FORMAT_ABGR_F32
+	PixelFormatABGR8888LE                     = C.ALLEGRO_PIXEL_FORMAT_ABGR_8888_LE
+	PixelFormatRGBA4444                       = C.ALLEGRO_PIXEL_FORMAT_RGBA_4444
+	PixelFormatSingleChannel8                 = C.ALLEGRO_PIXEL_FORMAT_SINGLE_CHANNEL_8
+	PixelFormatCompressedRGBADXT1             = C.ALLEGRO_PIXEL_FORMAT_COMPRESSED_RGBA_DXT1
+	PixelFormatCompressedRGBADXT3             = C.ALLEGRO_PIXEL_FORMAT_COMPRESSED_RGBA_DXT3
+	PixelFormatCompressedRGBADXT5             = C.ALLEGRO_PIXEL_FORMAT_COMPRESSED_RGBA_DXT5
+)