为什么片段着色器不会编译？

Question

我在许多Windows 7和8 PC上使用了下面的片段着色器而没有任何问题。

#ifndef STRINGIFY
#define STRINGIFY(a) #a
#endif

char *fsFont  = STRINGIFY(

precision mediump float;
varying vec2 v_texCoord;
vec2 v_texCoord;
uniform sampler2D s_texture;
uniform vec4      vColor4;

varying lowp vec4 DestinationColor;

void main()
{
  gl_FragColor = vec4( 1, 1, 1, texture2D( s_texture, v_texCoord).a ) * vColor4;
}

);

最近我尝试在Windows 10机器上运行我的应用程序，当我尝试编译着色器时出现以下错误：

0x0059f3dc "0(1) : warning C7022: unrecognized profile specifier "mediump"
0(1) : warning C7022: unrecognized profile specifier "precision"
0(1) : error C1038: declaration of "v_texCoord" conflicts with previous declaration at 0(1)
0(1) : error C0000: syntax error, u"

如果我评论出precision mediump float线..

0x0137f2c8 "0(1) : error C0000: syntax error, unexpected identifier, expecting "::" at token "lowp"
"

有什么问题？是因为我正在使用的PC支持不同版本的OpenGL而不是我期待的吗？

更新：This post建议精确媒体浮动线仅适用于OpenGL ES。这仍然无法解释为什么它适用于我的大多数PC。继续，lowp宣言有什么问题？

这是我的SDL初始化代码，它选择OpenGL配置文件/版本：

#ifndef _WIN32
  SDL_GL_SetAttribute( SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES );
  SDL_GL_SetAttribute( SDL_GL_CONTEXT_MAJOR_VERSION, 2 );
  SDL_GL_SetAttribute( SDL_GL_CONTEXT_MINOR_VERSION, 0 );
#else
  // Use OpenGL 3.1 core 
  SDL_GL_SetAttribute( SDL_GL_CONTEXT_MAJOR_VERSION, 3 );
  SDL_GL_SetAttribute( SDL_GL_CONTEXT_MINOR_VERSION, 1 ); 
  SDL_GL_SetAttribute( SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE );
#endif

更新：这是更新的着色器，现在正在运行，感谢大家的评论：

char *fsFont  = 

"#version 330
"
"precision mediump float;
"
"varying vec2 v_texCoord;
"

"uniform sampler2D s_texture;"
"uniform vec4      vColor4;"

"varying lowp vec4 DestinationColor;"

"void main()"
"{"
  "gl_FragColor = vec4( 1, 1, 1, texture2D( s_texture, v_texCoord).a ) * vColor4;"
"}"

;

更新：我已从所有着色器中删除了STRINGIFY，转移到OpenGL 3.3。我的所有着色器都编译为一个例外：

    char *vs3DShader  = 

    "#version 330
"
    "layout (location = 0) in vec3 Position;"
    "layout (location = 1) in vec4 color;"
    "layout (location = 2) in vec3 normal;"

    "out vec4 frag_color;"

    "uniform mat4 transform;"

    "void main()"
    "{"
    "  gl_Position = transform * vec4( Position.x, Position.y, Position.z, 1.0 );"

    "  // Pass vertex color to fragment shader.."
    "  frag_color = color;"
    "}"
;

错误：

0x0055f370 "(0) : error C0000: syntax error, unexpected $end at token "<EOF>"
"