#include "debug.hpp"
-#include "simulation.h"
#include "program.hpp"
+#include "simulation.h"
#include <GL/glew.h>
#include <GLUT/glut.h>
+#include <array>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <glm/ext.hpp>
#include <glm/glm.hpp>
+#include <sys/stat.h>
#include <vector>
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+bool debugContDist = false;
+
using namespace std;
using namespace glm;
-// calculate continuous distribution
-void calcContDist(Clouds *clds);
-
-float w(int i, int j, int k) { return 1; }
-
-const float metaballR = 1;
-float metaballField(float r) {
+const float metaballR = 1.5f;
+inline float metaballField(float r) {
if (r > metaballR)
return 0;
const float a = r / metaballR;
(22.f / 9.f * powf(a, 2)) + 1;
}
-/* const float normalizationFactor = 748.f / 405.f * M_PI * metaballR; */
-
-void calcContDist(Clouds *clds, float t) {
- const int i0 = 2, j0 = 2, k0 = 2, t0 = 2;
- const float divisor =
- 1.f / ((2 * t0 + 1) * (2 * k0 + 1) * (2 * j0 + 1) * (2 * i0 + 1));
- float sum = 0;
- for (int i = 0; i < CLOUD_DIM; i++) {
- for (int j = 0; j < CLOUD_DIM; j++) {
- for (int k = 0; k < CLOUD_DIM; k++) {
-
- // inner sums
- /* for (int tp = -t0, tp < t0; tp++) { */
- for (int ip = -i0; ip < i0; ip++) {
- for (int jp = -j0; jp < j0; jp++) {
- for (int kp = -k0; kp < k0; kp++) {
-
- sum += w(ip, jp, kp) * (float)clds->cld[i + ip][j + jp][k + kp];
- }
- }
- }
- /* } */
-
- clds->contDist[i][j][k] = sum / divisor;
- }
- }
- }
-}
+const float normalizationFactor = 748.f / 405.f * M_PI * metaballR;
void checkError() {
if (GLenum e = glGetError()) {
}
}
-vector<vec4> bbColors;
-
GLuint bbProg;
GLuint bbVao;
// These textures then go on the billboards
// The texture stores attenuation ratio?
-#define NQ 1
+#define NQ 64
GLuint bbTexIds[NQ];
// Stores attenuation ratio inside r channel
// Should be highest value at center
void precalculateBillboardTextures() {
+ fprintf(stderr, "Calculating billboard textures...\n");
+ glGenTextures(NQ, bbTexIds);
+
+ for (int d = 0; d < NQ; d++) {
float data[32 * 32];
+ for (int j = 0; j < 32; j++) {
+ for (int i = 0; i < 32; i++) {
// TODO: properly calculate this instead of whatever this is
- for (int j = 0; j < 32; j++)
- for (int i = 0; i < 32; i++)
- data[i + j * 32] = fmin(1.f, 0.5f + 2.f * (distance(vec2(i, j), vec2(16, 16)) / 16));
+ float r = distance(vec2(i, j), vec2(16, 16)) / 16;
+ float density = (float)d / NQ;
+ data[i + j * 32] =
+ 1 - (density * metaballField(r) / normalizationFactor);
+ }
+ }
- glGenTextures(NQ, bbTexIds);
+ mkdir("bbtex", 0777);
+ char path[32];
+ snprintf(path, 32, "bbtex/%i.tga", d);
+ saveGrayscale(data, 32, 32, path);
- for (int i = 0; i < NQ; i++) {
- glBindTexture(GL_TEXTURE_2D, bbTexIds[i]);
+ glBindTexture(GL_TEXTURE_2D, bbTexIds[d]);
checkError();
glTexImage2D(GL_TEXTURE_2D, 0, GL_RED, 32, 32, 0, GL_RED, GL_FLOAT, data);
glGenerateMipmap(GL_TEXTURE_2D); // required, otherwise texture is blank
checkError();
+
+ fprintf(stderr, "\r%i out of %i densities calculated%s", d + 1, NQ,
+ d == NQ - 1 ? "\n" : "");
}
}
struct Metaball {
vec3 pos;
- float r;
+ /** Radius, density */
+ float r, d;
+ vec4 col;
};
-// TODO: why is the x axis flipped??
-/* vector<Metaball> metaballs = {{{-0.5, 0.5, 0.5}, 0.25}, */
-/* {{-0.3, 0.5, 0.3}, 0.25}}; */
-vector<Metaball> metaballs = {{{0, 0, 0.5}, 1.f},
- {{0, 0.3, 0.3}, 0.7f}};
+
+array<Metaball, CLOUD_DIM * CLOUD_DIM * CLOUD_DIM> metaballs;
Clouds cs;
void calculateMetaballs() {
- /* stepClouds(&cs); */
- metaballs.clear();
- for (int i = 0; i < 256; i++) {
- float x = ((float)rand()/(float)(RAND_MAX) - 0.5) * 2;
- float y = ((float)rand()/(float)(RAND_MAX) - 0.5) * 2;
- float z = ((float)rand()/(float)(RAND_MAX) - 0.5) * 2;
- float r = (float)rand()/(float)(RAND_MAX) * 1;
- Metaball m = {{x,y,z}, r};
- metaballs.push_back(m);
- }
- /* for (int i = 0; i < CLOUD_DIM; i++) { */
- /* for (int j = 0; j < CLOUD_DIM; j++) { */
- /* for (int k = 0; k < CLOUD_DIM; k++) { */
- /* if (cs.cld[i][j][k]) { */
- /* Metaball m = {{i / (float)CLOUD_DIM, j / (float)CLOUD_DIM, k / (float)CLOUD_DIM}, */
- /* 1.f / (float)CLOUD_DIM }; */
- /* m.pos = (m.pos * vec3(2)) - vec3(1); */
+ stepClouds(&cs);
+ /* for (int i = 0; i < 256; i++) { */
+ /* float x = ((float)rand()/(float)(RAND_MAX) - 0.5) * 2; */
+ /* float y = ((float)rand()/(float)(RAND_MAX) - 0.5) * 2; */
+ /* float z = ((float)rand()/(float)(RAND_MAX) - 0.5) * 2; */
+ /* float r = (float)rand()/(float)(RAND_MAX) * 1; */
+ /* Metaball m = {{x,y,z}, r}; */
/* metaballs.push_back(m); */
/* } */
- /* } */
- /* } */
- /* } */
- fprintf(stderr, "num metaballs: %lu\n", metaballs.size());
+ for (int i = 0; i < CLOUD_DIM; i++) {
+ for (int j = 0; j < CLOUD_DIM; j++) {
+ for (int k = 0; k < CLOUD_DIM; k++) {
+ Metaball m = {
+ {i / (float)CLOUD_DIM, j / (float)CLOUD_DIM, k / (float)CLOUD_DIM},
+ 1.f / (float)CLOUD_DIM};
+ m.pos = (m.pos * vec3(2)) - vec3(1);
+ m.d = cs.q[i][j][k];
+ metaballs[i * CLOUD_DIM * CLOUD_DIM + j * CLOUD_DIM + k] = m;
+ }
+ }
+ }
}
vec3 sunPos = {0, 2, 2}, sunDir = {0, -1, -1};
GLuint attenuationTex;
void shadeClouds() {
-
- bbColors.clear();
-
glDisable(GL_DEPTH_TEST);
// shaderOutput * 0 + buffer * shader alpha
glBlendFunc(GL_ZERO, GL_SRC_ALPHA);
});
glActiveTexture(GL_TEXTURE0);
- glBindTexture(GL_TEXTURE_2D, bbTexIds[0]);
glUniform1i(glGetUniformLocation(bbProg, "tex"), 0);
GLuint modelLoc = glGetUniformLocation(bbProg, "model");
- for (auto k : metaballs) {
+ for (auto &k : metaballs) {
// place the billboard at the center of k
mat4 model = scale(translate(mat4(1), k.pos), vec3(k.r) * 2.f);
// i.e. multiply rather than add
// but glTexEnv is for the old fixed function pipeline --
// need to just tell our fragment shader then to modulate
+ int dIdx = k.d * NQ;
+ glBindTexture(GL_TEXTURE_2D, bbTexIds[dIdx]);
glUniform1i(glGetUniformLocation(bbProg, "modulate"), 1);
// Render the billboard.
// 1. First get position in opengl screen space: from [-1,1]
// 2. Normalize to [0,1]
// 3. Multiply by (width * height)
- vec2 screenPos = ((vec2(proj * view * model * vec4(0,0,0,1)) + vec2(1)) / vec2(2))
- * vec2(width, height);
+ vec2 screenPos =
+ ((vec2(proj * view * model * vec4(0, 0, 0, 1)) + vec2(1)) / vec2(2)) *
+ vec2(width, height);
vec4 pixel;
- glReadPixels(screenPos.x, screenPos.y, 1, 1, GL_RGBA, GL_FLOAT, value_ptr(pixel));
- /* if (pixel.g == 0 && pixel.b == 0) abort(); */
- /* fprintf(stderr, "pixel:"); */
- /* dump(pixel); */
+ // TODO: This is a huge bottleneck
+ glReadPixels(screenPos.x, screenPos.y, 1, 1, GL_RGBA, GL_FLOAT,
+ value_ptr(pixel));
// Multiply the pixel value by the sunlight color.
vec4 sunColor = {1, 1, 0.9, 1};
pixel *= sunColor;
// Store the color into an array C[k] as the color of the billboard.
- bbColors.push_back(pixel);
+ k.col = pixel;
}
saveFBO();
return distance(camPos, a.pos) > distance(camPos, b.pos);
});
+ glUniform1i(glGetUniformLocation(bbProg, "debugContDist"), debugContDist);
+
glDisable(GL_DEPTH_TEST);
glEnable(GL_BLEND);
// shaderOutput * 1 + buffer * shader alpha
glBlendFunc(GL_ONE, GL_SRC_ALPHA);
+
+ glActiveTexture(GL_TEXTURE0);
+ glUniform1i(glGetUniformLocation(bbProg, "tex"), 0);
+
for (int i = 0; i < metaballs.size(); i++) {
Metaball k = metaballs[i];
glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));
// Set the billboard color as C[n].
- fprintf(stderr, "bbColors[i]: ");
- dump(bbColors[i]);
- /* bbColors[i].x = 1 - bbColors[i].x; */
- /* bbColors[i].y = 1 - bbColors[i].y; */
- /* bbColors[i].z = 1 - bbColors[i].z; */
- bbColors[i].w = 1;
+ k.col.w = 1;
glUniform4fv(glGetUniformLocation(bbProg, "color"), 1,
- glm::value_ptr(bbColors[i]));
+ glm::value_ptr(k.col));
// Map the billboard texture.
- glActiveTexture(GL_TEXTURE0);
- glBindTexture(GL_TEXTURE_2D, bbTexIds[0]);
- glUniform1i(glGetUniformLocation(bbProg, "tex"), 0);
+ int dIdx = k.d * NQ;
+ glBindTexture(GL_TEXTURE_2D, bbTexIds[dIdx]);
// Don't modulate it -- blend it
glUniform1i(glGetUniformLocation(bbProg, "modulate"), 0);
+ if (debugContDist) {
+ glUniform1f(glGetUniformLocation(bbProg, "density"), k.d);
+ glDisable(GL_BLEND);
+ model = scale(model, vec3(0.02));
+ glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));
+ }
+
// Render the billboard with the blending function.
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
}
}
+bool needsReshading = true;
void display() {
+ if (needsReshading) {
// TODO: find a way to make sure there's no clipping
view = glm::lookAt(sunPos + sunDir * vec3(20), sunPos, {0, 1, 0});
proj = glm::ortho(1.f * aspect, -1.f * aspect, -1.f, 1.f, znear, zfar);
glClearColor(1, 1, 1, 1);
glClear(GL_COLOR_BUFFER_BIT);
shadeClouds();
+ needsReshading = false;
+ }
view = glm::lookAt(camPos, viewPos, {0, 1, 0});
proj = glm::perspective(45.f, aspect, znear, zfar);
void keyboard(unsigned char key, int x, int y) {
if (key == ' ') {
calculateMetaballs();
- glutPostRedisplay();
+ needsRedisplay = true;
+ needsReshading = true;
+ }
+ if (key == 'd') {
+ debugContDist = !debugContDist;
+ needsRedisplay = true;
}
}
firstMouse = false;
}
float dx = x - prevMouseX, dy = y - prevMouseY;
- prevMouseX = x; prevMouseY = y;
+ prevMouseX = x;
+ prevMouseY = y;
const vec3 origin(0, 18, 0);
const float sensitivity = 0.003f;
auto camMat = translate(mat4(1), origin + camPos);
needsRedisplay = true;
}
+void passiveMotion(int x, int y) {
+ prevMouseX = x;
+ prevMouseY = y;
+}
+
int main(int argc, char **argv) {
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGB |
glutKeyboardFunc(keyboard);
glutMotionFunc(motion);
+ glutPassiveMotionFunc(passiveMotion);
glutTimerFunc(16, timer, 0);
// set up billboard prog