I'm trying to draw a simple polygon in iOS, but I always end up with a blank glClearColor'ed screen. When I compile the cross-platform code for the desktop, it works.

I've implemented my own matrix functions, set up the shaders properly with "lowp, mediump" appearing only in the mobile version. I don't even get errors with the shaders or OpenGL on desktop or mobile.

From this I've guessed that the problem must be in my rendering code, but I copied the code from a tutorial project that does work and I still can't get anything to render.

Here is my sprite rendering code

//Mobile Renderer
		static const float POSITION[ 8 ] = {
			0.0f, 0.0f, // Down left (pivot point)
			1.0f, 0.0f, // Up left
			0.0f, 1.0f, // Down right
			1.0f, 1.0f  // Up right
		};
		
		glUseProgram(Graphics->currentShader->getProgram());
		
		//Graphics->setMatrixMode(SINNCA_MODELVIEW_MATRIX);
		//Graphics->loadIdentity();
		//Graphics->scale(100.0f, 100.0f, 0.0f);
		
		GLint att = glGetAttribLocation(Graphics->currentShader->getProgram(), "position");
		// returns 0, so that was successful

		glEnableVertexAttribArray(att);
		glVertexAttribPointer(att, 2, GL_FLOAT, GL_FALSE, 0, POSITION);
		glUniformMatrix4fv(Graphics->currentShader->uniformMVMatrix, 1, GL_FALSE, (float*)Graphics->getModelMatrix()); // also works

		glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
		
		/*//Desktop Renderer. With the matrices and shader this works perfectly
		glBindBuffer(GL_ARRAY_BUFFER, vBuffer);
		
		glBufferSubData(GL_ARRAY_BUFFER, 0, 4 * sizeof(vertex), vertices);
		glTexCoordPointer(2, GL_FLOAT, sizeof(vertex), (GLvoid*)offsetof(vertex, texco));
		glVertexPointer(2, GL_FLOAT, sizeof(vertex), (GLvoid*)offsetof(vertex, position));
		
		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, iBuffer);
		
		glUniformMatrix4fv(Graphics->currentShader->uniformMVMatrix, 1, GL_FALSE, (float*)Graphics->getModelMatrix());
		glEnableVertexAttribArray(Graphics->currentShader->attributePosition);
		glVertexAttribPointer(Graphics->currentShader->attributePosition, 2, GL_FLOAT, GL_FALSE, 0, 0);
		
		glDrawElements(GL_TRIANGLE_STRIP, 4, GL_UNSIGNED_INT, NULL);
		//glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
		 */

Is there something wrong with the code or am I forgetting another step?

I disabled all of the graphics states and got it to work, thank you!

Now I can figure out which one was causing the problem (right after I get some sleep first).