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):
29 depth_buf.set_min_filter(LINEAR);
30 depth_buf.storage(DEPTH_COMPONENT, size, size, 0);
31 depth_buf.image(0, DEPTH_COMPONENT, UNSIGNED_BYTE, 0);
32 depth_buf.parameter(GL_DEPTH_TEXTURE_MODE, GL_LUMINANCE);
33 depth_buf.parameter(GL_TEXTURE_COMPARE_MODE, GL_COMPARE_R_TO_TEXTURE);
34 depth_buf.parameter(GL_TEXTURE_COMPARE_FUNC, GL_LEQUAL);
35 depth_buf.parameter(GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
36 depth_buf.parameter(GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
37 fbo.attach(DEPTH_ATTACHMENT, depth_buf, 0);
38 glDrawBuffer(GL_NONE);
39 Framebuffer::unbind();
43 void ShadowMap::set_target(const Vector3 &t, float r)
49 void ShadowMap::prepare()
51 const Vector4 &lpos=light.get_position();
53 throw Exception("Non-directional lights not supported at the moment");
56 if(abs(lpos.z)>=abs(lpos.x) && abs(lpos.z)>=abs(lpos.y))
58 float d=sqrt(lpos.x*lpos.x+lpos.z*lpos.z);
62 matrix[1]=-lpos.x*lpos.y/d;
64 matrix[9]=-lpos.z*lpos.y/d;
68 float d=sqrt(lpos.x*lpos.x+lpos.y*lpos.y);
72 matrix[1]=-lpos.x*lpos.z/d;
73 matrix[5]=-lpos.y*lpos.z/d;
81 matrix[12]=-(target.x*matrix[0]+target.y*matrix[4]+target.z*matrix[8]);
82 matrix[13]=-(target.x*matrix[1]+target.y*matrix[5]+target.z*matrix[9]);
83 matrix[14]=-(target.x*matrix[2]+target.y*matrix[6]+target.z*matrix[10]);
90 matrix_mode(PROJECTION);
93 ortho(-radius, radius, -radius, radius, -radius, radius);
94 matrix_mode(MODELVIEW);
99 glViewport(0, 0, size, size);
100 glClear(GL_DEPTH_BUFFER_BIT);
103 matrix_mode(PROJECTION);
105 matrix_mode(MODELVIEW);
109 depth_buf.bind_to(3);
111 float s_eq[4]={ matrix[0]/diam, matrix[4]/diam, matrix[8]/diam, matrix[12]/diam+0.5 };
112 float t_eq[4]={ matrix[1]/diam, matrix[5]/diam, matrix[9]/diam, matrix[13]/diam+0.5 };
113 float r_eq[4]={ -matrix[2]/diam, -matrix[6]/diam, -matrix[10]/diam, 0.5-matrix[14]/diam-4.0/size };
114 glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
115 glTexGenfv(GL_S, GL_EYE_PLANE, s_eq);
116 enable(GL_TEXTURE_GEN_S);
117 glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
118 glTexGenfv(GL_T, GL_EYE_PLANE, t_eq);
119 enable(GL_TEXTURE_GEN_T);
120 glTexGeni(GL_R, GL_TEXTURE_GEN_MODE, GL_EYE_LINEAR);
121 glTexGenfv(GL_R, GL_EYE_PLANE, r_eq);
122 enable(GL_TEXTURE_GEN_R);
124 TexUnit::activate(0);
127 void ShadowMap::cleanup()
129 TexUnit::activate(3);
131 disable(GL_TEXTURE_GEN_S);
132 disable(GL_TEXTURE_GEN_T);
133 disable(GL_TEXTURE_GEN_R);
134 TexUnit::activate(0);