Why doesn't Xcode recognize these shaders?

I'm trying to teach myself Xcode, Objective-C, iOS app development, and GLSL all at once. (Probably not advisable, I know. ;-) I've been modifying the GLCameraRipple example, and had a lot of success so far! But I got stumped today when I tried to create some new vertex and fragment shaders.

The example comes with shaders called "Shader.vsh" and "Shader.fsh". I used File->Duplicate to make copies of them, which I called "Reflection.vsh" and "Reflection.fsh" respectively. The problem is that I can't get Xcode to recognize the new shaders. This code, which loads up the original vertex shader, works just fine:

vertShaderPathname = [[NSBundle mainBundle] pathForResource:@"Shader" ofType:@"vsh"];
NSLog(@"Original vertex shader should be here: %@", vertShaderPathname);
if (![self compileShader:&vertShader type:GL_VERTEX_SHADER file:vertShaderPathname]) {
    NSLog(@"Failed to compile original vertex shader");
    return NO;
}

But this code, which tries to load my new "Reflection.vsh" shader, fails. Specifically, the reflectVertShaderPathname string comes back with a value of (null).

reflectVertShaderPathname = [[NSBundle mainBundle] pathForResource:@"Reflection" ofType:@"vsh"];
NSLog(@"Reflection vertex shader should be here: %@", reflectVertShaderPathname);
if (![self compileShader:&reflectVertShader type:GL_VERTEX_SHADER file:reflectVertShaderPathname]) {
    NSLog(@"Failed to compile reflection vertex shader");
    return NO;
}

What do I have to do to make this work? I can't even tell where to start: is Xcode failing to include my new shaders in the NSBundle it makes when compiling this for the iPad? What magic voodoo do I have to invoke to convince Xcode to load up my new shaders? (Or am I looking for answers in the wrong place entirely?) Has anyone else run into a similar problem before?

Inspecting the "project.pbxproj" file in a text editor, I noticed a section where the shaders are being treated differently:

/* Begin PBXResourcesBuildPhase section */
            B66E3E2C13E9E79C00D2ACF0 /* Resources */ = {
                    isa = PBXResourcesBuildPhase;
                    buildActionMask = 2147483647;
                    files = (
                            B66E3E4713E9E79C00D2ACF0 /* Shader.fsh in Resources */,
                            B66E3E4913E9E79C00D2ACF0 /* Shader.vsh in Resources */,
                            B66E3E4F13E9E79C00D2ACF0 /* RippleViewController_iPhone.xib in Resources */,
                            B66E3E5213E9E79C00D2ACF0 /* RippleViewController_iPad.xib in Resources */,
                            B6388B2C141AB58300DA02FB /* Icon-72.png in Resources */,
                            B6388B2D141AB58300DA02FB /* Icon-Small-50.png in Resources */,
                            B6388B2E141AB58300DA02FB /* Icon-Small.png in Resources */,
                            B6388B2F141AB58300DA02FB /* Icon-Small@2x.png in Resources */,
                            B6388B30141AB58300DA02FB /* Icon.png in Resources */,
                            B6388B31141AB58300DA02FB /* Icon@2x.png in Resources */,
                            C3E55C21175C49F9007C299D /* Default-568h@2x.png in Resources */,
                    );
                    runOnlyForDeploymentPostprocessing = 0;
            };
/* End PBXResourcesBuildPhase section */

/* Begin PBXSourcesBuildPhase section */
            B66E3E2A13E9E79C00D2ACF0 /* Sources */ = {
                    isa = PBXSourcesBuildPhase;
                    buildActionMask = 2147483647;
                    files = (
                            B66E3E4113E9E79C00D2ACF0 /* main.m in Sources */,
                            B66E3E4513E9E79C00D2ACF0 /* AppDelegate.m in Sources */,
                            B66E3E4C13E9E79C00D2ACF0 /* RippleViewController.m in Sources */,
                            B6670DB413E9FD9F00AEF9EC /* RippleModel.m in Sources */,
                            C359BF4D175EA71C00D801B9 /* Reflection.fsh in Sources */,
                            C359BF4F175EA72A00D801B9 /* Reflection.vsh in Sources */,
                    );
                    runOnlyForDeploymentPostprocessing = 0;
            };
/* End PBXSourcesBuildPhase section */

So it looks like "Shader.vsh" is in something called "Resources", and "Reflection.vsh" is in something called "Sources". I assume that's part of the problem. But (a) what does that even mean, and (b) how should I fix it? Is it safe to just edit project.pbxproj in a text editor???

Solution

You've almost got it - xcode needs to know these are resources that need to be copied over, not source. No need to edit project files by hand, it's easy to fix in xcode:

Select your project (from the column on the left)
Select your target
Select the build phases tab
If the shaders appear in "compile sources", remove them
Add your shaders to "copy bundle resources"

That's it! Keep in mind, you'll have to do this for every new shader you add.