volmetrics
changeset 25:4b6c952a83bd
works
todo:
1- ta quads na nai to res tou volume * 2
2- conservative quad
3- to aspect ratio tou preview
| author | Eleni Maria Stea <elene.mst@gmail.com> |
|---|---|
| date | Sun, 27 Apr 2014 18:13:44 +0300 |
| parents | c4662d60cd93 |
| children | 5ee081af59b8 |
| files | data/shaders/vol.f.glsl data/shaders/vol.v.glsl notes src/main.cc |
| diffstat | 4 files changed, 154 insertions(+), 46 deletions(-) [+] |
line diff
1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000 1.2 +++ b/data/shaders/vol.f.glsl Sun Apr 27 18:13:44 2014 +0300 1.3 @@ -0,0 +1,40 @@ 1.4 +varying vec3 pt; 1.5 + 1.6 +uniform sampler3D tex; 1.7 +uniform float tmin; 1.8 +uniform float tmax; 1.9 +uniform vec3 res; 1.10 + 1.11 +float transfer(float x, float tmin, float tmax) 1.12 +{ 1.13 + float dt = 0.25 * (tmax - tmin); 1.14 + return smoothstep(tmin - dt, tmin + dt, x) * 1.15 + (1.0 - smoothstep(tmax - dt, tmax + dt, x)); 1.16 +} 1.17 + 1.18 +vec3 calc_normal(vec3 p, float texel) 1.19 +{ 1.20 + vec3 offs = 1.0 / res; 1.21 + 1.22 + float dfdx = texture3D(tex, p + vec3(offs.x, 0.0, 0.0)).x - texel; 1.23 + float dfdy = texture3D(tex, p + vec3(0.0, offs.y, 0.0)).x - texel; 1.24 + float dfdz = texture3D(tex, p + vec3(0.0, 0.0, offs.z)).x - texel; 1.25 + 1.26 + return normalize(vec3(dfdx, dfdy, dfdz)); 1.27 +} 1.28 + 1.29 +void main() 1.30 +{ 1.31 + const vec3 ldir = vec3(-1.0, 1.0, 2.0); 1.32 + 1.33 + if(max(pt.x, max(pt.y, pt.z)) > 1.0 || min(pt.x, min(pt.y, pt.z)) < 0.0) 1.34 + discard; 1.35 + 1.36 + float texel = texture3D(tex, pt).x; 1.37 + float val = transfer(texel, tmin, tmax); 1.38 + 1.39 + vec3 normal = calc_normal(pt, texel); 1.40 + float ndotl = max(dot(normalize(ldir), normal), 0.0); 1.41 + 1.42 + gl_FragColor = vec4(ndotl, ndotl, ndotl, val); 1.43 +}
2.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000 2.2 +++ b/data/shaders/vol.v.glsl Sun Apr 27 18:13:44 2014 +0300 2.3 @@ -0,0 +1,16 @@ 2.4 +#version 120 2.5 + 2.6 +varying vec3 pt; 2.7 + 2.8 +void main() 2.9 +{ 2.10 + mat4 mvbb = gl_ModelViewMatrix; 2.11 + 2.12 + mvbb[0][0] = mvbb[1][1] = mvbb[2][2] = 1.0; 2.13 + mvbb[0][1] = mvbb[0][2] = mvbb[1][2] = 0.0; 2.14 + mvbb[1][0] = mvbb[2][0] = mvbb[2][1] = 0.0; 2.15 + 2.16 + gl_Position = gl_ProjectionMatrix * mvbb * gl_Vertex; 2.17 + 2.18 + pt = (transpose(gl_NormalMatrix) * gl_Vertex.xyz) * 0.5 + 0.5; 2.19 +}
3.1 --- a/notes Thu Apr 24 21:33:26 2014 +0300 3.2 +++ b/notes Sun Apr 27 18:13:44 2014 +0300 3.3 @@ -1,12 +1,3 @@ 3.4 -na balw to t tou gui -1000 ws 1000 k na ginetai map sto 0 ws 1 3.5 - 3.6 -interpolation stin eval 3.7 - 3.8 -optimisations 3.9 - 3.10 -VBO 3.11 - 3.12 -******************* 3.13 -MOTION sto main.cc pros to kontinotero akro: 3.14 -map to x apo pixel se [0,1] k.a. 3.15 -************ 3.16 +a = density 3.17 +normals 3.18 +me to gradient: prev k epomeno
4.1 --- a/src/main.cc Thu Apr 24 21:33:26 2014 +0300 4.2 +++ b/src/main.cc Sun Apr 27 18:13:44 2014 +0300 4.3 @@ -25,7 +25,10 @@ 4.4 static void reshape_xfer(int x, int y); 4.5 static void mouse_xfer(int button, int state, int x, int y); 4.6 static void motion_xfer(int x, int y); 4.7 -static void volume_preview (); 4.8 +static void volume_preview(); 4.9 +static void draw_slices(); 4.10 +static void draw_iso(); 4.11 +static void draw_volume(); 4.12 4.13 static int mainwin_id, xferwin_id; 4.14 //todo keyb esc 4.15 @@ -37,18 +40,23 @@ 4.16 static const char *vol_fname = "data/test1.vol"; 4.17 static const char *vsdr_path = "data/shaders/transfer.v.glsl"; 4.18 static const char *fsdr_path = "data/shaders/transfer.f.glsl"; 4.19 +static const char *vsdr_vol_path = "data/shaders/vol.v.glsl"; 4.20 +static const char *fsdr_vol_path = "data/shaders/vol.f.glsl"; 4.21 + 4.22 +static unsigned int sprog; 4.23 +static unsigned int sprog_vol; 4.24 4.25 static Volume *vol; 4.26 static Mesh *mesh; 4.27 static float cur_z, thres = 0.5, thres2 = 1.0; 4.28 -static float slice_z; 4.29 +static float slice_z = 0.5; 4.30 4.31 static int use_orig_vol_res = 1; 4.32 static int vol_res[3]; // volume sampling resolution x/y/z 4.33 4.34 static GLUI *ui; 4.35 4.36 -static unsigned int sprog; 4.37 +static int num_poly = 128; 4.38 4.39 int main(int argc, char **argv) 4.40 { 4.41 @@ -89,6 +97,8 @@ 4.42 glEnable(GL_LIGHT0); 4.43 glLightModeli(GL_LIGHT_MODEL_TWO_SIDE, 1); 4.44 4.45 + glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); 4.46 + 4.47 //FIXME shaders setup 4.48 if(!(sprog = sdr_getprog(vsdr_path, fsdr_path))) 4.49 { 4.50 @@ -96,6 +106,12 @@ 4.51 return false; 4.52 } 4.53 4.54 + if(!(sprog_vol = sdr_getprog(vsdr_vol_path, fsdr_vol_path))) 4.55 + { 4.56 + fprintf(stderr, "Failed to create shader program!\n"); 4.57 + return false; 4.58 + } 4.59 + 4.60 vol = new Volume; 4.61 if(!vol->load(vol_fname)) { 4.62 fprintf(stderr, "Failed to load %s", vol_fname); 4.63 @@ -195,7 +211,6 @@ 4.64 { 4.65 float aspect = win_xsz / win_ysz; 4.66 4.67 - glDisable(GL_LIGHTING); 4.68 glDisable(GL_DEPTH_TEST); 4.69 4.70 glUseProgram(sprog); 4.71 @@ -213,16 +228,16 @@ 4.72 glMatrixMode(GL_PROJECTION); 4.73 glPushMatrix(); 4.74 glLoadIdentity(); 4.75 - glOrtho(-aspect, aspect, -1.0, 1.0, -1.0, 1.0); 4.76 + glOrtho(0, aspect, 0, 1, -1, 1); 4.77 4.78 glBindTexture(GL_TEXTURE_3D, vol->get_texture()); 4.79 glEnable(GL_TEXTURE_3D); 4.80 glBegin(GL_QUADS); 4.81 glColor3f(1.0, 1.0, 1.0); 4.82 - glTexCoord3f(0, 0, slice_z); glVertex3f(-1.0, 1.0, 0.0); 4.83 - glTexCoord3f(0, 1, slice_z); glVertex3f(-1.0, 0.5, 0.0); 4.84 - glTexCoord3f(1, 1, slice_z); glVertex3f(-0.5, 0.5, 0.0); 4.85 - glTexCoord3f(1, 0, slice_z); glVertex3f(-0.5, 1.0, 0.0); 4.86 + glTexCoord3f(0, 0, slice_z); glVertex3f(0, 1, 0); 4.87 + glTexCoord3f(0, 1, slice_z); glVertex3f(0, 0.75, 0); 4.88 + glTexCoord3f(1, 1, slice_z); glVertex3f(0.25, 0.75, 0); 4.89 + glTexCoord3f(1, 0, slice_z); glVertex3f(0.25, 1, 0); 4.90 glEnd(); 4.91 glDisable(GL_TEXTURE_3D); 4.92 4.93 @@ -244,7 +259,72 @@ 4.94 glUseProgram(0); 4.95 4.96 glEnable(GL_DEPTH_TEST); 4.97 - glEnable(GL_LIGHTING); 4.98 +} 4.99 + 4.100 +static void draw_slices() 4.101 +{ 4.102 + glBindTexture(GL_TEXTURE_3D, vol->get_texture()); 4.103 + glEnable(GL_TEXTURE_3D); 4.104 + glBegin(GL_QUADS); 4.105 + glTexCoord3f(0, 0, cur_z); glVertex3f(-1, -1, 0); 4.106 + glTexCoord3f(0, 1, cur_z); glVertex3f(-1, 1, 0); 4.107 + glTexCoord3f(1, 1, cur_z); glVertex3f(1, 1, 0); 4.108 + glTexCoord3f(1, 0, cur_z); glVertex3f(1, -1, 0); 4.109 + glEnd(); 4.110 + glDisable(GL_TEXTURE_3D); 4.111 +} 4.112 + 4.113 +static void draw_iso() 4.114 +{ 4.115 + if(mesh->is_empty()) { 4.116 + printf("recalculating isosurface ... "); 4.117 + fflush(stdout); 4.118 + vol->create_mesh(mesh, thres, thres2, vol_res[0], vol_res[1], vol_res[2]); 4.119 + printf("done.\n"); 4.120 + } 4.121 + mesh->draw(); 4.122 +} 4.123 + 4.124 +static void draw_volume() 4.125 +{ 4.126 + glUseProgram(sprog_vol); 4.127 + 4.128 + int tmin_loc = glGetUniformLocation(sprog_vol, "tmin"); 4.129 + if(tmin_loc != -1) 4.130 + glUniform1f(tmin_loc, std::min(thres, thres2)); 4.131 + int tmax_loc = glGetUniformLocation(sprog_vol, "tmax"); 4.132 + if(tmax_loc != -1) 4.133 + glUniform1f(tmax_loc, std::max(thres, thres2)); 4.134 + 4.135 + const Image *img = vol->get_slice(0); 4.136 + int res_x = img->get_width(); 4.137 + int res_y = img->get_height(); 4.138 + int res_z = vol->get_slice_count(); 4.139 + int res_loc = glGetUniformLocation(sprog_vol, "res"); 4.140 + if(res_loc != -1) 4.141 + glUniform3f(res_loc, (float)res_x, (float)res_y, (float)res_z); 4.142 + 4.143 + glDisable(GL_DEPTH_TEST); 4.144 + glBindTexture(GL_TEXTURE_3D, vol->get_texture()); 4.145 + glEnable(GL_TEXTURE_3D); 4.146 + glEnable(GL_BLEND); 4.147 + glBegin(GL_QUADS); 4.148 + for(int i=0; i<num_poly; i++) 4.149 + { 4.150 + float tex_z = (float)i / (float)num_poly; 4.151 + float z = 2 * tex_z - 1; 4.152 + 4.153 + glTexCoord3f(0, 0, tex_z); glVertex3f(-2, -2, z * 2); 4.154 + glTexCoord3f(0, 1, tex_z); glVertex3f(-2, 2, z * 2); 4.155 + glTexCoord3f(1, 1, tex_z); glVertex3f(2, 2, z * 2); 4.156 + glTexCoord3f(1, 0, tex_z); glVertex3f(2, -2, z * 2); 4.157 + } 4.158 + glEnd(); 4.159 + glDisable(GL_BLEND); 4.160 + glDisable(GL_TEXTURE_3D); 4.161 + glEnable(GL_DEPTH_TEST); 4.162 + 4.163 + glUseProgram(0); 4.164 } 4.165 4.166 static void display(void) 4.167 @@ -257,26 +337,9 @@ 4.168 glRotatef(cam_phi, 1, 0, 0); 4.169 glRotatef(cam_theta, 0, 1, 0); 4.170 4.171 -/* 4.172 - glBindTexture(GL_TEXTURE_3D, vol->get_texture()); 4.173 - glEnable(GL_TEXTURE_3D); 4.174 - glBegin(GL_QUADS); 4.175 - glTexCoord3f(0, 0, cur_z); glVertex3f(-1, -1, 0); 4.176 - glTexCoord3f(0, 1, cur_z); glVertex3f(-1, 1, 0); 4.177 - glTexCoord3f(1, 1, cur_z); glVertex3f(1, 1, 0); 4.178 - glTexCoord3f(1, 0, cur_z); glVertex3f(1, -1, 0); 4.179 - glEnd(); 4.180 - glDisable(GL_TEXTURE_3D); 4.181 -*/ 4.182 - 4.183 -/* if(mesh->is_empty()) { 4.184 - printf("recalculating isosurface ... "); 4.185 - fflush(stdout); 4.186 - vol->create_mesh(mesh, thres, thres2, vol_res[0], vol_res[1], vol_res[2]); 4.187 - printf("done.\n"); 4.188 - } 4.189 - mesh->draw(); 4.190 -*/ 4.191 + //draw_slices(); 4.192 + //draw_iso(); 4.193 + draw_volume(); 4.194 4.195 volume_preview(); 4.196 glutSwapBuffers(); 4.197 @@ -290,10 +353,8 @@ 4.198 glLoadIdentity(); 4.199 gluPerspective(45, (float)x / (float)y, 0.5, 500); 4.200 4.201 - if(x != win_xsz || y != win_ysz) { 4.202 - win_xsz = x; 4.203 - win_ysz = y; 4.204 - } 4.205 + win_xsz = x; 4.206 + win_ysz = y; 4.207 } 4.208 4.209 static void keyboard(unsigned char key, int x, int y)