Why isn't this texture repeating in iOS OpenGL ES 2.0?

Question

I have a class which renders a textured 2D shape onto the screen in iOS. If I use texture coordinates less than 1.0, the texture scales appropriately to match the coordinates. However, if I use texture coordinates of more than 1.0, the texture scales correctly, but doesn't repeat itself as I expected. Instead, it just draws the texture once and repeats the edge pixels across the rest of the shape (I do hope that makes sense :/ )

Is there a way to turn on Repeating Textures in OpenGL ES 2.0 with GLKit?

The rendering function is:

-(void)render
{
    // If we have a texture set, setup the Texture Environment Mode
    if (texture != nil) {
        self.effect.texture2d0.envMode = GLKTextureEnvModeReplace;
        self.effect.texture2d0.target = GLKTextureTarget2D;
        self.effect.texture2d0.name = texture.name;
    }

    // Perform any Transformations on the Sprite
    GLKMatrix4 modelViewMatrix = GLKMatrix4Multiply(
        GLKMatrix4MakeTranslation(self.position.x, self.position.y, 0.0f),
        GLKMatrix4MakeRotation(GLKMathDegreesToRadians(self.rotation), 0, 0, 1)
    );

    self.effect.transform.modelviewMatrix = modelViewMatrix;

    // Prepare to Draw
    [self.effect prepareToDraw];

    // Setup the Vertices
    glEnableVertexAttribArray(GLKVertexAttribPosition);
    glVertexAttribPointer(GLKVertexAttribPosition, 2, GL_FLOAT, GL_FALSE, 0, self.vertices);

    // Setup the Texture Coordinates
    if (texture != nil) {
        glEnableVertexAttribArray(GLKVertexAttribTexCoord0);
        glVertexAttribPointer(GLKVertexAttribTexCoord0, 2, GL_FLOAT, GL_FALSE, 0, self.texCoords);
    }

    // Enable Alpha Blending for Transparent PNGs
    glEnable(GL_BLEND);
    glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);

    // Draw the Triangle Strip from the Vertex Array
    glDrawArrays(GL_TRIANGLE_STRIP, 0, self.numVertices);

    // Disable Alpha Blending
    glDisable(GL_BLEND);

    // Disable Texture Environment
    if (texture != nil) {
        glDisableVertexAttribArray(GLKVertexAttribTexCoord0);
    }

    glDisableVertexAttribArray(GLKVertexAttribPosition);
}

Answer 1

When you're creating your texture you can set the mode used for handling the edges. Set the mode to REPEAT instead of CLAMP_TO_EDGE (which is apparently the default), like this:

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);