2018-06-08 2. bgfx iOS 上 使用 Metal

苹果强推 Metal，cocos2d-x 论坛里也有讨论：

https://discuss.cocos2d-x.org/t/opengl-is-deprecated-in-10-14-mojave/42732/11?u=yinjimmy
https://discuss.cocos2d-x.org/t/what-if-cocos2d-x-switched-to-bgfx/42742

但是帖子被锁住了，不能回帖了。

默认的 iOS 工程是不使用 Metal 的，得自己修改。

diff --git a/examples/common/entry/entry_ios.mm b/examples/common/entry/entry_ios.mm
index 569e99f5..2c35b381 100644
--- a/examples/common/entry/entry_ios.mm
+++ b/examples/common/entry/entry_ios.mm
@@ -14,7 +14,7 @@
 #if __IPHONE_8_0 && !TARGET_IPHONE_SIMULATOR  // check if sdk/target supports metal
 #   import 
 #   import 
-//#   define HAS_METAL_SDK
+#   define HAS_METAL_SDK
 #endif

或者添加预编译宏 HAS_METAL_SDK，这里直接修改源代码，避免生成工程需要再修改项目工程。

观察 log 输出：

2018-06-08 16:41:43.662469+0800 examplesDebug[8227:4058019] [DYMTLInitPlatform] platform initialization successful
2018-06-08 16:41:43.969076+0800 examplesDebug[8227:4057914] +[CATransaction synchronize] called within transaction
2018-06-08 16:41:44.002333+0800 examplesDebug[8227:4057914] Metal GPU Frame Capture Enabled
2018-06-08 16:41:44.003685+0800 examplesDebug[8227:4057914] Metal API Validation Enabled
2018-06-08 16:41:44.032471+0800 examplesDebug[8227:4058036] /Users/admin/repos/game-engine/bgfx/src/bgfx.cpp (2898): BGFX Init...

2018-06-08 16:41:44.033308+0800 examplesDebug[8227:4058036] /Users/admin/repos/game-engine/bgfx/src/bgfx.cpp (1433): BGFX Application called bgfx::renderFrame directly, not creating render thread.

2018-06-08 16:41:44.033337+0800 examplesDebug[8227:4058036] /Users/admin/repos/game-engine/bgfx/src/bgfx.cpp (1449): BGFX Running in multi-threaded mode

2018-06-08 16:41:44.196267+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (390): BGFX Init.

2018-06-08 16:41:44.274888+0800 examplesDebug[8227:4058036] /Users/admin/repos/game-engine/bgfx/src/bgfx.cpp (1184): BGFX 

2018-06-08 16:41:44.274979+0800 examplesDebug[8227:4058036] /Users/admin/repos/game-engine/bgfx/src/bgfx.cpp (1210): BGFX Supported renderer backends (3):

2018-06-08 16:41:44.275027+0800 examplesDebug[8227:4058036] /Users/admin/repos/game-engine/bgfx/src/bgfx.cpp (1213): BGFX    - Noop

2018-06-08 16:41:44.275044+0800 examplesDebug[8227:4058036] /Users/admin/repos/game-engine/bgfx/src/bgfx.cpp (1213): BGFX    - Metal

2018-06-08 16:41:44.275060+0800 examplesDebug[8227:4058036] /Users/admin/repos/game-engine/bgfx/src/bgfx.cpp (1213): BGFX    - OpenGL ES 2.0

2018-06-08 16:41:44.275075+0800 examplesDebug[8227:4058036] /Users/admin/repos/game-engine/bgfx/src/bgfx.cpp (1216): BGFX 

... 省略

2018-06-08 16:41:44.360802+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2610): BGFX Texture   0: R8 (requested: R8), layers 1, 2048x24 RT[.], WO[.], CW[.], sRGB[.]

2018-06-08 16:41:44.361480+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2340): BGFX Vertex Shader consts 1

2018-06-08 16:41:44.361672+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2340): BGFX Fragment Shader consts 0

2018-06-08 16:41:44.361843+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2411): BGFX attr a_color0: 0

2018-06-08 16:41:44.361872+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2411): BGFX attr a_color1: 1

2018-06-08 16:41:44.361893+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2411): BGFX attr a_position: 2

2018-06-08 16:41:44.361922+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2411): BGFX attr a_texcoord0: 3

2018-06-08 16:41:44.361978+0800 examplesDebug[8227:4057914] vertexdecl 74c34f26 (d443ed7f), stride 28

2018-06-08 16:41:44.362019+0800 examplesDebug[8227:4057914]     attr 0 - Attrib::Position, num 3, type 4, norm 0, asint 0, offset 0

2018-06-08 16:41:44.362084+0800 examplesDebug[8227:4057914]     attr 4 - Attrib::Color0, num 4, type 0, norm 1, asint 0, offset 12

2018-06-08 16:41:44.362124+0800 examplesDebug[8227:4057914]     attr 5 - Attrib::Color1, num 4, type 0, norm 1, asint 0, offset 16

2018-06-08 16:41:44.362163+0800 examplesDebug[8227:4057914]     attr 10 - Attrib::TexCoord0, num 2, type 4, norm 0, asint 0, offset 20

2018-06-08 16:41:44.362431+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2340): BGFX Vertex Shader consts 0

2018-06-08 16:41:44.363276+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2340): BGFX Fragment Shader consts 1

2018-06-08 16:41:44.363600+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2411): BGFX attr a_position: 0

2018-06-08 16:41:44.363650+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2340): BGFX Fragment Shader consts 1

2018-06-08 16:41:44.363771+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2411): BGFX attr a_position: 0

2018-06-08 16:41:44.364013+0800 examplesDebug[8227:4057914] /Users/admin/repos/game-engine/bgfx/src/renderer_mtl.mm (2340): BGFX Fragment Shader consts 1

iPhone 4s 测试

clang: fatal error: optimization flag '-fomit-frame-pointer' is not supported for target 'armv7' [-Wignored-optimization-argument]