Setting a background color for the window when opening it, before starting the rendering

[mat007]

Operating System

• Windows
• macOS
• Linux
• FreeBSD
• OpenBSD
• Android
• iOS
• Nintendo Switch
• Xbox
• Web Browsers

What feature would you like to be added?

A way to control the initialization of the window when the game opens up, e.g. at least be able to set a color.

Why is this needed?

My game intro screen has a black background, and when launching it, there is a not very pleasing white background that flashes in the window, before the first draw.

This can be reproduced by running the paint example with the following changes:

diff --git a/examples/paint/main.go b/examples/paint/main.go
index de3b5df1..362977b0 100644
--- a/examples/paint/main.go
+++ b/examples/paint/main.go
@@ -27,8 +27,8 @@ import (
 )

 const (
-       screenWidth  = 640
-       screenHeight = 480
+       screenWidth  = 1024
+       screenHeight = 768
 )

 var (
@@ -76,7 +76,7 @@ func NewGame() *Game {
        g := &Game{
                canvasImage: ebiten.NewImage(screenWidth, screenHeight),
        }
-       g.canvasImage.Fill(color.White)
+       g.canvasImage.Fill(color.Black)
        return g
 }

The bigger the window, the more visible it seems to be.

[hajimehoshi]

I am not sure this is controllable. Let me investigate this

[mat007]

Thanks @hajimehoshi !

On Windows I believe it could just be doing

wc.hbrBackground = …

in

ebiten/internal/goglfw/win32window_windows.go

Line 1351 in 3b67b91

func registerWindowClassWin32() error {

passing it a brush.

But I have no clue for other platforms.

I’m also thinking I could perhaps delay the showing of the window after it’s been created somehow, to make sure there is at least one rendering that’s been done?