public static void Paint(this TextureImage image, IGUIContext ctx, Rectangle dest)
{
if (image.IsDisposed || image.TextureID < 0)
{
image.LogWarning("Image is not loaded (has no TextureID).");
return;
}
if (dest.Width < 0 || dest.Height < 0 || !ctx.ClipBoundStack.IsOnScreen(dest))
{
return;
}
using (new PaintWrapper(RenderingFlags.HighQuality)) {
GL.Enable(EnableCap.Blend);
BlendingFactor srcBlend = BlendingFactor.SrcAlpha;
BlendingFactor destBlend = BlendingFactor.OneMinusSrcAlpha;
BlendEquationMode mode = BlendEquationMode.FuncAdd;
if (image.Opacity < 1)
{
// Multiply
srcBlend = BlendingFactor.DstColor;
destBlend = BlendingFactor.OneMinusSrcAlpha;
GL.Color4(image.Opacity, image.Opacity, image.Opacity, image.Opacity);
}
else
{
// mandatory here,
// but take care not to forget the f for float
// otherwise there is a dangreous overloading with uint
// which would set a very different value
if (image.BlendColor != Color.Empty)
{
GL.Color4(image.BlendColor);
}
else
{
GL.Color4(1f, 1f, 1f, 1f);
}
}
GL.BlendEquation(mode);
GL.BlendFunc(srcBlend, destBlend);
GL.Enable(EnableCap.Texture2D);
GL.BindTexture(TextureTarget.Texture2D, image.TextureID);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.Linear);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int)TextureWrapMode.ClampToEdge);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int)TextureWrapMode.ClampToEdge);
GL.Begin(PrimitiveType.Quads);
GL.TexCoord2(0, 0);
GL.Vertex3(dest.X, dest.Y, 0);
GL.TexCoord2(1, 0);
GL.Vertex3(dest.X + dest.Width, dest.Y, 0);
GL.TexCoord2(1, 1);
GL.Vertex3(dest.X + dest.Width, dest.Y + dest.Height, 0);
GL.TexCoord2(0, 1);
GL.Vertex3(dest.X, dest.Y + dest.Height, 0);
GL.End();
};
}
