paper lights

diff --git a/sdr/sky.f.glsl b/sdr/sky.f.glsl
index 4b830fe..e1787ac 100644 (file)
--- a/sdr/sky.f.glsl
+++ b/sdr/sky.f.glsl
@@ -1,5 +1,7 @@
 varying vec3 local_pos;
 
+uniform float alpha;
+
 #define PI     3.141592653589793
 #define TWO_PI (2.0 * PI)
 
@@ -21,7 +23,7 @@ void main()
        vec3 skycol = mix(col_hor, col_zen, alt);
 
        gl_FragColor.rgb = mix(skycol, vec3(0.0, 0.0, 0.0), cval);
-       gl_FragColor.a = 1.0;
+       gl_FragColor.a = alpha;
 }
 
 const float cloud_dens = 0.25;

diff --git a/src/geom.cc b/src/geom.cc
index 770b438..dae21f5 100644 (file)
--- a/src/geom.cc
+++ b/src/geom.cc
@@ -144,7 +144,7 @@ void ground()
        glPopMatrix();
 }
 
-void xlogo(float sz, float alpha, float xcircle)
+void xlogo(float sz, const float *col_ink, const float *col_paper, float alpha, float xcircle)
 {
        static const float xlogo_varr[] = {
                -0.500, 0.407, -0.113, -0.109, 0.059, -0.006, -0.251, 0.407,
@@ -168,7 +168,7 @@ void xlogo(float sz, float alpha, float xcircle)
        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
        glBegin(GL_QUADS);
-       glColor4f(0, 0, 0, alpha);
+       glColor4f(col_ink[0], col_ink[1], col_ink[2], alpha);
        const float *vptr = xlogo_varr;
        for(int i=0; i<(int)(sizeof xlogo_varr / sizeof *xlogo_varr) / 2; i++) {
                glVertex2fv(vptr);
@@ -200,7 +200,7 @@ void xlogo(float sz, float alpha, float xcircle)
                float width = 0.05f * tcol;
                float z = -cos(theta) * 0.1;
 
-               glColor4f(0.9, 0.9, 0.9, tcol);
+               glColor4f(col_paper[0], col_paper[1], col_paper[2], tcol);
                glTexCoord2f(0, 1.0f - tcol);
                glVertex3f(sin(theta) * (rad + width), cos(theta) * (rad + width), z);
                glTexCoord2f(1, 1.0f - tcol);

diff --git a/src/geom.h b/src/geom.h
index fb8e60a..a55063c 100644 (file)
--- a/src/geom.h
+++ b/src/geom.h
@@ -6,6 +6,6 @@ void destroy_geom();
 
 void faros();
 void ground();
-void xlogo(float sz, float alpha, float xcircle);
+void xlogo(float sz, const float *col_ink, const float *col_paper, float alpha, float xcircle);
 
 #endif /* GEOM_H_ */

diff --git a/src/main.cc b/src/main.cc
index 02f631e..cc6024f 100644 (file)
--- a/src/main.cc
+++ b/src/main.cc
@@ -17,6 +17,11 @@
 #define BEAM_ENERGY 0.01
 #define BEAM_LEN 16.0
 #define BEAM_DEF_SPEED 0.1
+#define BEAM_HEIGHT            4.65
+
+#define XLOGO_RAD      0.5
+
+#define LERP(a, b, t)  ((a) + ((b) - (a)) * (t))
 
 struct Camera {
        float x, y, z;
@@ -29,7 +34,8 @@ static void cleanup();
 
 static void display();
 static void light();
-static void backdrop();
+static void paper_light();
+static void backdrop(float alpha);
 static void help();
 
 static void idle();
@@ -50,11 +56,14 @@ long tmsec, prev_tmsec, anim_time;
 bool anim_stopped;
 
 static const float sil_color[] = {0.05, 0.02, 0.1, 1.0};
+static const float ink_color[] = {0.05, 0.15, 0.3, 1.0};
 static const float beam_color[] = {0.5, 0.4, 0.2, 1.0};
+static const float paper_color[] = {0.9, 0.8, 0.8, 1.0};
 
 static float beam_angle, beam_speed;
 static float beam_len;
-static float xlogo_alpha;
+static float xlogo_alpha, xcircle;
+static float paper;
 
 static bool show_help, show_ui = true;
 
@@ -120,10 +129,13 @@ static bool init()
        add_seq_track("cam-z", INTERP_SIGMOID, EXTRAP_CLAMP, 0);
        add_seq_track("xlogo", INTERP_SIGMOID, EXTRAP_CLAMP, 0);
        add_seq_track("xcircle", INTERP_SIGMOID, EXTRAP_CLAMP, 1);
+       add_seq_track("paper", INTERP_SIGMOID, EXTRAP_CLAMP, 0);
        load_seq("seq");
 
        freecam = seq_track_empty("cam-theta");
 
+       glClearColor(paper_color[0], paper_color[1], paper_color[2], 1);
+
        start_time = glutGet(GLUT_ELAPSED_TIME);
        prev_tmsec = start_time;
        return true;
@@ -149,8 +161,10 @@ static void display()
                anim_time = anim_stop_time - start_time;
        }
 
+       paper = get_seq_value("paper", anim_time);
+
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-       backdrop();
+       backdrop(1.0f - paper);
 
        glMatrixMode(GL_MODELVIEW);
        glLoadIdentity();
@@ -169,7 +183,12 @@ static void display()
        glRotatef(cam.theta, 0, 1, 0);
        glTranslatef(-cam.x, -cam.y, -cam.z);
 
-       glColor3fv(sil_color);
+       float color[3];
+       color[0] = LERP(sil_color[0], ink_color[0], paper);
+       color[1] = LERP(sil_color[1], ink_color[1], paper);
+       color[2] = LERP(sil_color[2], ink_color[2], paper);
+
+       glColor3fv(color);
        ground();
        faros();
 
@@ -178,15 +197,15 @@ static void display()
        beam_angle += beam_speed * 360.0f * dt;
 
        xlogo_alpha = get_seq_value("xlogo", anim_time);
-       float xcircle = get_seq_value("xcircle", anim_time);
+       xcircle = get_seq_value("xcircle", anim_time);
 
        if(xlogo_alpha > 0.0) {
                glPushMatrix();
                float beam_angle_rad = beam_angle / 180.0 * M_PI;
                float xlogo_dist = beam_len;
                float xlogo_pos[3] = {sin(beam_angle_rad), 0, cos(beam_angle_rad)};
-               glTranslatef(xlogo_pos[0] * xlogo_dist, xlogo_pos[1] * xlogo_dist + 4.7, xlogo_pos[2] * xlogo_dist);
-               xlogo(0.5, xlogo_alpha, xcircle);
+               glTranslatef(xlogo_pos[0] * xlogo_dist, xlogo_pos[1] * xlogo_dist + BEAM_HEIGHT, xlogo_pos[2] * xlogo_dist);
+               xlogo(XLOGO_RAD, color, paper_color, xlogo_alpha, xcircle);
                glPopMatrix();
        }
 
@@ -195,6 +214,8 @@ static void display()
        light();
        glPopMatrix();
 
+       paper_light();
+
        if(show_ui) {
                ui();
        }
@@ -208,12 +229,15 @@ static void display()
 
 static void light()
 {
+       float beam_alpha = 1.0 - paper;
+       if(beam_alpha <= 0.0f) return;
+
        glPushAttrib(GL_ENABLE_BIT);
        glDisable(GL_CULL_FACE);
 
        glPushMatrix();
 
-       glTranslatef(0, 4.65, 0.2);
+       glTranslatef(0, BEAM_HEIGHT, 0.2);
        bind_program(sdr_beam);
        set_uniform_float(sdr_beam, "beam_len", beam_len);
 
@@ -228,7 +252,7 @@ static void light()
                float alpha = BEAM_ENERGY / (t * t);
 
                if(i == 0) continue;
-               glColor4f(beam_color[0], beam_color[1], beam_color[2], alpha);
+               glColor4f(beam_color[0], beam_color[1], beam_color[2], alpha * beam_alpha);
 
                glutSolidCylinder(rad, beam_len, 12, 1);
        }
@@ -242,13 +266,50 @@ static void light()
        glPopAttrib();
 }
 
-static void backdrop()
+static void paper_light()
+{
+       glPushAttrib(GL_ENABLE_BIT);
+       glDisable(GL_CULL_FACE);
+
+       glEnable(GL_BLEND);
+       glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
+       glPushMatrix();
+       glRotatef(beam_angle, 0, 1, 0);
+       glTranslatef(0, BEAM_HEIGHT, 0.3);
+
+       float rad = BEAM_RMIN + (BEAM_RMAX - BEAM_RMIN) * 0.6f;
+       float maxdist = beam_len - 0.6f;
+       float end_rad = XLOGO_RAD * 0.4;
+
+       glLineWidth(3);
+       glBegin(GL_LINES);
+       glColor4f(ink_color[0], ink_color[1], ink_color[2], paper);
+
+       glVertex3f(0, rad, 0);
+       glVertex3f(0, end_rad, maxdist);
+       glVertex3f(0, -rad, 0);
+       glVertex3f(0, -end_rad, maxdist);
+       glEnd();
+
+       glPopMatrix();
+       glPopAttrib();
+}
+
+static void backdrop(float alpha)
 {
+       glPushAttrib(GL_ENABLE_BIT);
+       glEnable(GL_BLEND);
+       glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
        glFrontFace(GL_CW);
        bind_program(sdr_sky);
+       set_uniform_float(sdr_sky, "alpha", alpha);
        glutSolidSphere(200, 16, 32);
        bind_program(0);
        glFrontFace(GL_CCW);
+
+       glPopAttrib();
 }
 
 static void help()
@@ -268,11 +329,13 @@ static void help()
                "   0 .............. clear beam rotation keyframes",
                "   [/] ............ change beam length and set keyframe",
                "   \\ .............. clear beam length keyframes",
-               "   <enter> ........ record automatic beam start/stop transition",
+               "   <enter> ........ record automatic beam stop transition",
                "   K .............. set camera keyframe",
                "   <shift>-L ...... clear all camera keyframes",
-               "   X .............. toggle X logo and set keyframe",
-               "   <shift>-X ...... clear logo keyframes",
+               "   X/Z ............ toggle X logo/circle and set keyframe",
+               "   <shift>-X/Z .... clear logo/circle keyframes",
+               "   P .............. toggle paper",
+               "   <shift>-P ...... clear paper keyframes",
                "   ~ .............. dump all animation keyframes to seq_dump",
                0
        };
@@ -345,7 +408,6 @@ static void reshape(int x, int y)
 static void keyboard(unsigned char c, int x, int y)
 {
        int idx;
-       static float orig_beam_speed;
        static Camera orig_cam;
        long anim_time = anim_stopped ? anim_stop_time - start_time : tmsec;
 
@@ -407,16 +469,8 @@ static void keyboard(unsigned char c, int x, int y)
        case '\n':
                idx = find_seq_track("beam-speed");
                assert(idx >= 0);
-               if(get_seq_value(idx, anim_time) > 0.0) {
-                       clear_seq_track(idx);
-                       set_seq_value(idx, anim_time, beam_speed);
-                       set_seq_value(idx, anim_time + 3000, 0);
-                       orig_beam_speed = beam_speed;
-               } else {
-                       clear_seq_track(idx);
-                       set_seq_value(idx, anim_time, 0);
-                       set_seq_value(idx, anim_time + 3000, orig_beam_speed);
-               }
+               set_seq_value(idx, anim_time, beam_speed);
+               set_seq_value(idx, anim_time + 2000, 0);
                break;
 
        case 'c':
@@ -465,6 +519,25 @@ static void keyboard(unsigned char c, int x, int y)
                clear_seq_track("xlogo");
                break;
 
+       case 'z':
+               set_seq_value("xcircle", anim_time, xcircle < 0.5 ? 1.0 : 0.0);
+               break;
+
+       case 'Z':
+               printf("clearing circle keyframes\n");
+               clear_seq_track("xcircle");
+               break;
+
+
+       case 'p':
+               set_seq_value("paper", anim_time, paper < 0.5 ? 1.0 : 0.0);
+               break;
+
+       case 'P':
+               printf("clearing paper keyframes\n");
+               clear_seq_track("paper");
+               break;
+
        case '`':
                printf("dumping animation data to: seq_dump\n");
                if(!dump_seq("seq_dump")) {