3 This file is part of libmspgl
4 Copyright © 2009 Mikko Rasa, Mikkosoft Productions
5 Distributed under the LGPL
13 #include "projection.h"
15 #include "shadowmap.h"
23 ShadowMap::ShadowMap(unsigned s, const Scene &c, const Light &l):
30 depth_buf.set_min_filter(LINEAR);
31 depth_buf.set_compare_enabled(true);
32 depth_buf.set_compare_func(LEQUAL);
33 depth_buf.set_wrap(CLAMP_TO_EDGE);
34 depth_buf.storage(DEPTH_COMPONENT, size, size, 0);
35 depth_buf.image(0, DEPTH_COMPONENT, UNSIGNED_BYTE, 0);
36 fbo.attach(DEPTH_ATTACHMENT, depth_buf, 0);
37 draw_buffer(NO_BUFFER);
38 Framebuffer::unbind();
41 void ShadowMap::set_target(const Vector3 &t, float r)
47 void ShadowMap::set_texture_unit(unsigned u)
52 void ShadowMap::prepare()
54 Vector4 lpos = light.get_position();
57 /* XXX Not really proper way to support positional lights, but good
58 enough when the light source is far away */
62 float d = sqrt(lpos.x*lpos.x+lpos.y*lpos.y+lpos.z*lpos.z);
69 if(abs(lpos.z)>=abs(lpos.x) && abs(lpos.z)>=abs(lpos.y))
71 float d = sqrt(lpos.x*lpos.x+lpos.z*lpos.z);
74 matrix[8] = -lpos.x/d;
75 matrix[1] = -lpos.x*lpos.y/d;
77 matrix[9] = -lpos.z*lpos.y/d;
81 float d = sqrt(lpos.x*lpos.x+lpos.y*lpos.y);
82 matrix[0] = -lpos.y/d;
85 matrix[1] = -lpos.x*lpos.z/d;
86 matrix[5] = -lpos.y*lpos.z/d;
94 matrix[12] = -(target.x*matrix[0]+target.y*matrix[4]+target.z*matrix[8]);
95 matrix[13] = -(target.x*matrix[1]+target.y*matrix[5]+target.z*matrix[9]);
96 matrix[14] = -(target.x*matrix[2]+target.y*matrix[6]+target.z*matrix[10]);
103 matrix_mode(PROJECTION);
106 ortho(-radius, radius, -radius, radius, -radius, radius);
107 matrix_mode(MODELVIEW);
111 const Framebuffer *old_fbo = Framebuffer::current();
113 clear(DEPTH_BUFFER_BIT);
114 scene.render("shadow");
116 matrix_mode(PROJECTION);
118 matrix_mode(MODELVIEW);
123 Framebuffer::unbind();
126 depth_buf.bind_to(unit);
127 float diam = radius*2;
128 float s_eq[4] = { matrix[0]/diam, matrix[4]/diam, matrix[8]/diam, matrix[12]/diam+0.5 };
129 float t_eq[4] = { matrix[1]/diam, matrix[5]/diam, matrix[9]/diam, matrix[13]/diam+0.5 };
130 float r_eq[4] = { -matrix[2]/diam, -matrix[6]/diam, -matrix[10]/diam, 0.5-matrix[14]/diam-4.0/size };
131 glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
132 glTexGenfv(GL_S, GL_EYE_PLANE, s_eq);
133 enable(GL_TEXTURE_GEN_S);
134 glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
135 glTexGenfv(GL_T, GL_EYE_PLANE, t_eq);
136 enable(GL_TEXTURE_GEN_T);
137 glTexGeni(GL_R, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
138 glTexGenfv(GL_R, GL_EYE_PLANE, r_eq);
139 enable(GL_TEXTURE_GEN_R);
141 TexUnit::activate(0);
144 void ShadowMap::cleanup()
146 Texture::unbind_from(unit);
147 disable(GL_TEXTURE_GEN_S);
148 disable(GL_TEXTURE_GEN_T);
149 disable(GL_TEXTURE_GEN_R);
150 TexUnit::activate(0);