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Shadow mapping with Traction engine
-----------------------------------

// TODO: Add info about blurring the depth buffer

Steps to get shadows into your scene:
1. Render scene from lights point of view 
2. Render scene from camera point of view

-----------------------------------

Steps explained:

1. Render scene from lights point of view 

	// -- Render 
	glExt.bindDepthFBO();	
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);		
	// Add offsets to remove z-fight
	glPolygonOffset(2.0f, 2.0f);
	glEnable(GL_POLYGON_OFFSET_FILL);

	gluLookAt( LOOK FROM LIGHT POSITION );

	// Store needed matrices for step 2
	Matrix4 light_mat_proj;
	glGetFloatv(GL_PROJECTION_MATRIX, light_mat_proj);
	Matrix4 light_mat_modelview;
	glGetFloatv(GL_MODELVIEW_MATRIX, light_mat_modelview);

	// Draw your scene here
	drawObjects();

	// -- End rendering to buffer
	glDisable(GL_POLYGON_OFFSET_FILL);
	glExt.unbindFBO();

2. Render scene from camera point of view

	gluLookAt( LOOK FROM CAMERA POSITION );

	glMatrixMode(GL_TEXTURE);
	glLoadIdentity();  
	glTranslatef(0.5, 0.5, 0.5); 	// [0.0, 1.0], not [-1.0, 1.0]
	glScalef(0.5, 0.5, 0.5);
	glMultMatrixf(light_mat_proj); 	// multiply texture matrix
	glMultMatrixf(light_mat_modelview);
	// finally, multiply by the *inverse* of the *current* modelview matrix
	Matrix4 s_mat_m;
	glGetFloatv(GL_MODELVIEW_MATRIX, s_mat_m);

	// Invert matrix
	s_mat_m = s_mat_m.makeInverseTranspose();
	s_mat_m = s_mat_m.makeTranspose();

	glMultMatrixf(s_mat_m);
	glMatrixMode(GL_MODELVIEW);

	// Bind your shadowmapping shader
	shaders.shadowMap->bind();

	// Bind shadow texture & pass it to shader
	glActiveTextureARB(GL_TEXTURE0_ARB);
	 glEnable(GL_TEXTURE_2D);
	 glBindTexture(GL_TEXTURE_2D, glExt.shadowMap);
	 shaders.jytky->setUniform1i("shadowMap", 0);  

	// Draw your scene here with lighting and stuff
	drawObjects();
	
	shaders.unbind();	
	
	// Restore normal texture matrix and stuff
	glMatrixMode(GL_TEXTURE);
	glLoadIdentity();
        glEnable(GL_TEXTURE_2D);
        glMatrixMode(GL_MODELVIEW);

-----------------------------------

If post procession is wanted on the shadowed scene
apply it after the texture matrix is restored. Otherwise
things will get messy :-)

-----------------------------------

Check the facts and maths from:
http://en.wikipedia.org/wiki/Shadow_mapping

-----------------------------------

 - rale 12.3.2007

Lightweight gui system 
----------------------
rale - 2006


Modify GUIinclude.h if you are not using SDL.


// INIT

GUIHolder *holder;	

holder  = new GUIHolder();
holder->init();

holder->addWidget(new GUIButton(125,635,14,14,"PREVIEW", "Preview"));
holder->addWidget(new GUIButton(125,665,14,14,"DOEFFECT", "Do effect"));
holder->addWidget(new GUIToggleButton(125,695,14,14,"UNDOLAST", "Undo last"),false);

// RENDER

holder->render(0); // float = deltatime (not needed currently..)

holder->processEvent(GUIMouseMovedEvent(event.motion.x,event.motion.y));
holder->processEvent(GUIKeyboardEvent(SDL_GetKeyName(event.key.keysym.sym), false, false));
holder->processEvent(GUIKeyboardEvent(SDL_GetKeyName(event.key.keysym.sym), true, false));
std::string returnvalue = holder->processEvent(GUIMousePressedEvent(event.motion.x,event.motion.y, false, true, false));

if(returnvalue == "PREVIEW") doPreview; //etc


// DEINIT

this->holder->deinit();

if(this->holder!=0) delete holder; 
holder = 0;
Traction + Brainstorm
Fairytale
for Breakpoint'07

 .Critikill .Bridgeclaw .Romeo Knight .Preacher .Rale
 .Kofeiini .Napsa .Axel
 
This version may run rather badly on old computers.
Sorry, that's our fault. Also, even though we were
told not to do any glowing lines, we did them anyway. 
Sorry about that too. Shader model 2.0 and
framebuffer objects are required. If it does not run, 
try upgrading your drivers.

Greetings to all our friends and enemies, you know
who you are. 
 
http://traction.untergrund.net
http://brainstorm.untergrund.net