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POOpenGL perspective and lighting not working?
 

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  1. POOpenGL perspective and lighting not working?
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    <p><strong>EDIT: A few people have said to use glNormal3f() to solve my lighting problem, but I researched and implemented that just now and it didn't change anything at all.</strong></p> <p>I'm kind of new to OpenGL so I guess I'm doing something wrong, but I followed the examples in the Red Book as closely as I could and I just can't figure out what's wrong, so I figured I'd try and ask you guys.</p> <p>I have two problems. One is that, even though I'm sure I'm using glFrustum correctly, it still renders an orthographic scene, and it renders objects that are both in front of and behind the camera for some reason. The other is that, even though I'm pretty sure I'm doing this lighting right (because I followed the example in the book), it's lighting the scene with a uniform color, no shading or anything. Here's my code:</p> <pre><code>#include "GraphicsManager.h" #include &lt;GL/gl.h&gt; void GraphicsManager::initialize () { fx = 0; fy = 0; glEnable (GL_LIGHTING); glEnable (GL_LIGHT0); glDepthFunc (GL_LEQUAL); glEnable (GL_DEPTH_TEST); glViewport (0, 0, 800, 600); glMatrixMode (GL_PROJECTION); glLoadIdentity (); glFrustum (-1.0, 1.0, -1.0, 1.0, 1.5, 20.0); glMatrixMode (GL_MODELVIEW); glLoadIdentity (); } int GraphicsManager::draw (std::vector&lt;float&gt; buttoninfo) { // changing light_position makes no difference GLfloat light_position[] = { 1.0, 1.0, 1.0, 1.0 }; int i, j, k; fx += buttoninfo[0]; fy += buttoninfo[1]; glClearColor (0.0, 0.0, 0.0, 1.0); glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glColor3f (0.5, 0.5, 0.8); glLoadIdentity (); glLightfv (GL_LIGHT0, GL_POSITION, light_position);� glRotatef (buttoninfo[3], 1.0, 0.0, 0.0); glRotatef (buttoninfo[2], 0.0, 1.0, 0.0); glTranslatef (-fx, 0, -fy); for (i = 0; i &lt; 5; i ++) { for (j = 0; j &lt; 5; j ++) { for (k = 0; k &lt; 5; k ++) { glPushMatrix (); glTranslatef (i, j, k); glBegin (GL_TRIANGLE_FAN); glVertex3f (0.0, 0.5, 0.0); glVertex3f (-0.5, -0.5, -0.5); glVertex3f (-0.5, -0.5, 0.5); glVertex3f (0.5, -0.5, 0.5); glVertex3f (0.5, -0.5, -0.5); glVertex3f (-0.5, -0.5, -0.5); glEnd (); glPopMatrix (); } } } glFlush (); return (int)buttoninfo[5]; } </code></pre> <p>Can you help me figure out what's wrong? Thanks in advance.</p>
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    1. USDarthFennec
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      1. VTDownMod
    1. COI don't why your projection is wrong, but you won't get proper lighting without normals (call `glNormal3f` before every call to `glVertex3f`).
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      1. USuser786653
    2. COTo deal with lighting you need to supply Normals along with Vertexes. See glNormal3f usage.
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      1. USKromster
 

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