ios - 为 Retina 和非 Retina 显示器开发 OpenGL ES

Question

在深入研究我的下一个项目之前，我正在寻求建议。我想支持 iOS 现在支持的所有各种分辨率(视网膜、非视网膜 iPhone 和所有 3 款 iPad)。

开发人员完成这项工作最常用的方法是什么？我看到过类似的问题，但具有特定的性质。我正在寻找完整的包裹。 IE。我想支持不同分辨率的位图字体、图像等。

是设备特定的开关，还是标准的 if 语句？

感谢所有先进的帮助。

E

编辑:我从 Apple 找到了这个:

Blockquote If your application uses OpenGL ES for rendering, your existing drawing code should continue to work without any changes. When drawn on a high-resolution screen, though, your content is scaled accordingly and will appear more blocky. The reason for the blocky appearance is that the default behavior of the CAEAGLLayer class, which you use to back your OpenGL ES renderbuffers , is the same as other Core Animation layer objects. In other words, its scale factor is set to 1.0 initially, which causes the Core Animation compositor to scale the contents of the layer on high-resolution screens. To avoid this blocky appearance, you need to increase the size of your OpenGL ES renderbuffers to match the size of the screen. (With more pixels, you can then increase the amount of detail you provide for your content.) Because adding more pixels to your renderbuffers has performance implications, though, you must explicitly opt in to support high-resolution screens.

Blockquote To enable high-resolution drawing, you must change the scale factor of the view you use to present your OpenGL ES content. Changing the contentScaleFactor property of your view from 1.0 to 2.0 triggers a matching change to the scale factor of the underlying CAEAGLLayer object. The renderbufferStorage:fromDrawable: method, which you use to bind the layer object to your renderbuffers, calculates the size of the renderbuffer by multiplying the layer’s bounds by its scale factor. Thus, doubling the scale factor doubles the width and height of the resulting renderbuffer, giving you more pixels for your content. After that, it is up to you to provide the content for those additional pixels.

所以我想我更新后的问题是如何将上述比例因子加倍？

编辑 2:

我快到了......

我正在使用它在我的 EAGLView 中进行缩放:

        // Adjust for retina displays
    if ([self respondsToSelector:@selector(setContentScaleFactor:)])
    {
            self.contentScaleFactor = [[UIScreen mainScreen] scale];
    }

现在剩下的唯一问题是起源不知何故搞砸了。显示图像现在根据分辨率缩放，但在较大的分辨率下，图像从屏幕中间开始。

请帮忙!

编辑 3:已解决!!!!我在方向上遇到了问题。

您需要确保您的翻译已更新。我用过这个:

    glTranslatef( width / 2, height /2, 0);
glRotatef(-90, 0, 0, 1);
glTranslatef(-1 * (height / 2),-1 * (width / 2),0);

感谢您的关注。我希望这对某人有所帮助。

Answer 1

查看 View 编程指南:View Geometry and Coordinate Systems

http://developer.apple.com/library/ios/#DOCUMENTATION/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html

Coordinate values are represented using floating-point numbers, which allow for precise layout and positioning of content regardless of the underlying screen resolution

这意味着您指定的点(GCRect 等...)不是像素 - 它是针对视网膜/非视网膜调整的点

最后，正如 Cocoa Priest 所说，您可以维护 png 图像和图像的 *@2x.png 版本:

Retina Display Images on iPhone

What is the point of the @2x for Retina display apps?

另外，这里有一篇关于 Retina 设计的文章: http://globalmoxie.com/blog/designing-for-iphone4-retina-display.shtml