Gracefully exit on a shader compile error

SinisterSoft

If you use a shader then on some systems that shader may not compile correctly (at run-time), this will result in an error that doesn't normally return properly to your program. Here is a way of doing it 'gracefully'...

local result,reply=pcall(Shader.new,"vShader","fShader",0,{         {name="vMatrix",type=Shader.CMATRIX,sys=Shader.SYS_WVP,vertex=true},         {name="fColor",type=Shader.CFLOAT4,sys=Shader.SYS_COLOR,vertex=false},         {name="fTexture",type=Shader.CTEXTURE,vertex=false},  },         {{name="vVertex",type=Shader.DFLOAT,mult=3,slot=0,offset=0},         {name="vColor",type=Shader.DUBYTE,mult=4,slot=1,offset=0},         {name="vTexCoord",type=Shader.DFLOAT,mult=2,slot=2,offset=0}, })              if result then         shader=reply     else         print("shader error:",reply)     end

Just replace the Shader.new paramaters with your parameters.

Because 'shader' will be nil if it fails then no harm done if you set a sprite to use that nil shader, as nil will just set the shader to the Gideros default.

Hope you all find this useful.