+#include "GL/glew.h"
#include "debug.hpp"
#include "program.hpp"
-#include "simulation.h"
-#include <GL/glew.h>
+#include "simulation.hpp"
#include <GLUT/glut.h>
#include <array>
+#include <chrono>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
-bool debugContDist = false;
+enum Mode { render, debugContDist, debugColor, debugProbExt, debugProbAct };
+Mode curMode = render;
using namespace std;
using namespace glm;
-const float metaballR = 1.5f;
+const float metaballR = 1.f / 16.f;
inline float metaballField(float r) {
- if (r > metaballR)
+ if (r > 1)
return 0;
- const float a = r / metaballR;
+ const float a = r / (1);
return (-4.f / 9.f * powf(a, 6)) + (17.f / 9.f * powf(a, 4)) -
(22.f / 9.f * powf(a, 2)) + 1;
}
-const float normalizationFactor = 748.f / 405.f * M_PI * metaballR;
+const float normalizationFactor = (748.f / 405.f) * M_PI;
void checkError() {
if (GLenum e = glGetError()) {
}
}
-GLuint bbProg;
+GLuint bbProg, sunProg;
GLuint bbVao;
// Here we need to generate n_q textures for different densities of metaballs
float r = distance(vec2(i, j), vec2(16, 16)) / 16;
float density = (float)d / NQ;
data[i + j * 32] =
- 1 - (density * metaballField(r) / normalizationFactor);
+ 1 -
+ fmin(1, (3 * density * (metaballField(r) / normalizationFactor)));
}
}
saveGrayscale(data, 32, 32, path);
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;
- /** Radius, density */
- float r, d;
+ ivec3 coords;
+ /** Density */
+ float d;
vec4 col;
};
-array<Metaball, CLOUD_DIM * CLOUD_DIM * CLOUD_DIM> metaballs;
+array<Metaball, CLOUD_DIM_X * CLOUD_DIM_Y * CLOUD_DIM_Z> metaballs;
+const float cloudScale = metaballR;
+const float metaballScale = metaballR * 1.5f;
Clouds cs;
void calculateMetaballs() {
/* 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++) {
- 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);
+ for (int i = 0; i < CLOUD_DIM_X; i++) {
+ for (int j = 0; j < CLOUD_DIM_Y; j++) {
+ for (int k = 0; k < CLOUD_DIM_Z; k++) {
+ Metaball m = {vec3(i, j, k) * vec3(cloudScale), {i, j, k}};
+ /* m.pos = (m.pos * vec3(2)) - (cloudScale / 2); */
+ m.pos -= vec3(CLOUD_DIM_X, CLOUD_DIM_Y, CLOUD_DIM_Z) * cloudScale / 2.f;
m.d = cs.q[i][j][k];
- metaballs[i * CLOUD_DIM * CLOUD_DIM + j * CLOUD_DIM + k] = m;
+ /* m.d = 0; */
+ metaballs[i * CLOUD_DIM_Y * CLOUD_DIM_Z + j * CLOUD_DIM_Z + k] = m;
}
}
}
+ /* for (int z = 0; z < CLOUD_DIM_Z; z++) */
+ /* metaballs[32 * CLOUD_DIM_Y * CLOUD_DIM_Z + 32 * CLOUD_DIM_Z + z].d = 1;
+ */
}
-vec3 sunPos = {0, 2, 2}, sunDir = {0, -1, -1};
-vec3 camPos = {0, 0, -5}, viewPos = {0, 0, 0};
+vec3 sunPos = {0, 5, 0}, sunDir = {0, -1, 0};
+size_t envColorIdx = 0;
+// First color is sun color, second is sky color
+std::array<std::array<vec4, 2>, 3> envColors{
+ {{vec4(1, 1, 1, 1), vec4(0.9, 1, 1, 1)},
+ {vec4(0.939, 0.632, 0.815, 1), vec4(0.9, 1, 1, 1)},
+ {vec4(0.999, 0.999, 0.519, 1), vec4(0.981, 0.667, 0.118, 1)}}};
+vec3 camPos = {0, 0, -3}, viewPos = {0, 0, 0};
mat4 proj; // projection matrix
mat4 view; // view matrix
float znear = 0.001, zfar = 1000;
-float width = 600, height = 400;
-float aspect = width / height;
+// for performance with glReadPixels these should be powers of 2!
+float width = 1200, height = 800;
void setProjectionAndViewUniforms(GLuint progId) {
GLuint projLoc = glGetUniformLocation(progId, "projection");
return m;
}
-GLuint attenuationTex;
+#define PBO
+
+/* const int shadeWidth = 256, shadeHeight = 256; */
+const int shadeWidth = 256, shadeHeight = 256;
+
+#ifdef PBO
+const int numPbos = 512;
+GLuint pboBufs[numPbos];
+GLbyte sink[shadeWidth * shadeHeight * 4];
+
+void inline mapPixelRead(int pboBuf, int metaball) {
+ glBindBuffer(GL_PIXEL_PACK_BUFFER, pboBufs[pboBuf]);
+ GLubyte *src =
+ (GLubyte *)glMapBufferRange(GL_PIXEL_PACK_BUFFER, 0,
+ 4 * sizeof(GLubyte), GL_MAP_READ_BIT);
+ vec4 pixel = vec4(src[0], src[1], src[2], src[3]) / vec4(255.f);
+ glUnmapBuffer(GL_PIXEL_PACK_BUFFER);
+
+ glBindBuffer(GL_PIXEL_PACK_BUFFER, 0);
+
+ // Multiply the pixel value by the sunlight color.
+ pixel *= envColors[envColorIdx][0];
+
+ // Store the color for the previous set of pixels
+ metaballs[metaball].col = pixel;
+}
+
+#endif
void shadeClouds() {
+
glDisable(GL_DEPTH_TEST);
// shaderOutput * 0 + buffer * shader alpha
glBlendFunc(GL_ZERO, GL_SRC_ALPHA);
glUniform1i(glGetUniformLocation(bbProg, "tex"), 0);
GLuint modelLoc = glGetUniformLocation(bbProg, "model");
+ glUniform1i(glGetUniformLocation(bbProg, "debug"), 0);
+
+ glViewport(0, 0, shadeWidth, shadeHeight);
+#ifdef PBO
+ int pboIdx = 0;
+#endif
+
+ auto begin_time = std::chrono::system_clock::now();
+ size_t i = 0;
for (auto &k : metaballs) {
+ /* fprintf(stderr, "\rShading metaball %lu/%lu...", i, metaballs.size()); */
// place the billboard at the center of k
- mat4 model = scale(translate(mat4(1), k.pos), vec3(k.r) * 2.f);
+ mat4 model = translate(mat4(1), k.pos);
// rotate the billboard so that its normal is oriented to the sun
model = faceView(model);
+ model = scale(model, vec3(metaballScale));
+
glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));
// Set the billboard color as RGBA = (1.0, 1.0, 1.0, 1.0).
// 1. First get position in opengl screen space: from [-1,1]
// 2. Normalize to [0,1]
// 3. Multiply by (width * height)
- vec2 screenPos =
+ ivec2 screenPos =
((vec2(proj * view * model * vec4(0, 0, 0, 1)) + vec2(1)) / vec2(2)) *
- vec2(width, height);
+ vec2(shadeWidth, shadeHeight);
+
+#ifndef PBO
vec4 pixel;
// TODO: This is a huge bottleneck
- glReadPixels(screenPos.x, screenPos.y, 1, 1, GL_RGBA, GL_FLOAT,
- value_ptr(pixel));
+ glReadPixels(screenPos.x, screenPos.y, 1, 1, GL_RGBA, GL_FLOAT, &pixel);
// Multiply the pixel value by the sunlight color.
- vec4 sunColor = {1, 1, 0.9, 1};
- pixel *= sunColor;
+ pixel *= envColors[envColorIdx][0];
// Store the color into an array C[k] as the color of the billboard.
k.col = pixel;
+#else
+
+ glBindBuffer(GL_PIXEL_PACK_BUFFER, pboBufs[pboIdx]);
+ // It would be nice if this worked. But it doesn't
+ // macOS driver does this synchronously
+ /* glReadPixels(screenPos.x, screenPos.y, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE,
+ */
+ /* NULL); */
+ glReadPixels(screenPos.x, screenPos.y, 64, 64, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+
+ int nextPbo = (pboIdx + 1) % numPbos;
+ if (i >= numPbos - 1) {
+ // start mapping the read values back
+ mapPixelRead(nextPbo, i - numPbos + 1);
}
+ pboIdx = nextPbo;
+#endif
+
+ i++;
+ }
+ /* fprintf(stderr, "\n"); */
+
+#ifdef PBO
+ // sink remaining reads
+ for (int i = 0; i < numPbos; i++) {
+ mapPixelRead(i, metaballs.size() - numPbos + i);
+ }
+#endif
+
+ auto elapsed = std::chrono::system_clock::now() - begin_time;
+ double elapsed_seconds =
+ std::chrono::duration_cast<std::chrono::duration<double>>(elapsed)
+ .count();
+ fprintf(stderr, "Time taken to shade: %fs\n", elapsed_seconds);
saveFBO();
checkError();
+ glViewport(0, 0, width, height);
}
-void renderObject() {}
+void renderObject() {
+ glDisable(GL_BLEND);
+ // render the sun
+ glUseProgram(sunProg);
+ mat4 model = translate(mat4(1), sunPos);
+ model = lookAt(sunPos, sunPos + sunDir, {0, 1, 0}) * model;
+ model = translate(scale(translate(model, -sunPos), vec3(0.3)), sunPos);
+ glUniformMatrix4fv(glGetUniformLocation(sunProg, "model"), 1, GL_FALSE,
+ glm::value_ptr(model));
+ glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
+}
void renderClouds() {
+ glUseProgram(bbProg);
+
// Sort metaballs in descending order from the viewpoint
sort(metaballs.begin(), metaballs.end(), [](Metaball &a, Metaball &b) {
return distance(camPos, a.pos) > distance(camPos, b.pos);
});
- glUniform1i(glGetUniformLocation(bbProg, "debugContDist"), debugContDist);
+ glUniform1i(glGetUniformLocation(bbProg, "debug"), curMode != render);
glDisable(GL_DEPTH_TEST);
glEnable(GL_BLEND);
// shaderOutput * 1 + buffer * shader alpha
glBlendFunc(GL_ONE, GL_SRC_ALPHA);
+ /* glBlendColor(1.f,1.f,1.f,1.f); */
+ /* glBlendFuncSeparate(GL_ONE, GL_SRC_ALPHA, GL_CONSTANT_ALPHA, GL_SRC_ALPHA);
+ */
+
glActiveTexture(GL_TEXTURE0);
glUniform1i(glGetUniformLocation(bbProg, "tex"), 0);
GLuint modelLoc = glGetUniformLocation(bbProg, "model");
// Place the billboard at the center of the corresponding metaball n.
- mat4 model = scale(translate(mat4(1), k.pos), vec3(k.r) * 2.f);
+ mat4 model = translate(mat4(1), k.pos);
// Rotate the billboard so that its normal is oriented to the viewpoint.
model = faceView(model);
+ model = scale(model, vec3(metaballScale));
+
glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));
// Set the billboard color as C[n].
glm::value_ptr(k.col));
// Map the billboard texture.
- int dIdx = k.d * NQ;
+ int dIdx = k.d * (NQ - 1);
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));
+ glUniform1f(glGetUniformLocation(bbProg, "debugColor"),
+ curMode == debugColor);
+ if (curMode != render) {
+ float debugVal = 0;
+ if (curMode == debugContDist)
+ debugVal = k.d;
+ else if (curMode == debugProbAct)
+ debugVal = cs.p_act[k.coords.x][k.coords.y][k.coords.z] / P_ACT;
+ else if (curMode == debugProbExt)
+ debugVal = cs.p_ext[k.coords.x][k.coords.y][k.coords.z] / P_EXT;
+ glUniform1f(glGetUniformLocation(bbProg, "debugVal"), debugVal);
+ glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+ model = scale(model, vec3(0.1));
glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));
}
}
}
-bool needsReshading = true;
+bool curBeenShaded = false;
+
void display() {
- if (needsReshading) {
+ if (!curBeenShaded && (curMode == render || curMode == debugColor)) {
// 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);
+ view = glm::lookAt(sunPos + sunDir * vec3(100.f), sunPos, {0, 0, 1});
+ // TODO: calculate bounds so everything is covered
+ proj = glm::ortho(2.5f, -2.5f, -2.5f, 2.5f, znear, 10000.f);
+ glUseProgram(bbProg);
setProjectionAndViewUniforms(bbProg);
glClearColor(1, 1, 1, 1);
glClear(GL_COLOR_BUFFER_BIT);
shadeClouds();
- needsReshading = false;
+ curBeenShaded = true;
}
view = glm::lookAt(camPos, viewPos, {0, 1, 0});
+ const float aspect = width / height;
proj = glm::perspective(45.f, aspect, znear, zfar);
+ glUseProgram(sunProg);
+ setProjectionAndViewUniforms(sunProg);
+ glUseProgram(bbProg);
setProjectionAndViewUniforms(bbProg);
- glClearColor(0.83, 1, 1, 1); // background color
+ vec4 skyColor = envColors[envColorIdx][1];
+ glClearColor(skyColor.r, skyColor.g, skyColor.b,
+ skyColor.a); // background color
glClear(GL_COLOR_BUFFER_BIT);
renderObject(); // render things that aren't clouds
renderClouds();
bool needsRedisplay = false;
void timer(int _) {
- /* calculateMetaballs(); */
if (needsRedisplay) {
glutPostRedisplay();
- needsRedisplay = false;
}
+ needsRedisplay = false;
glutTimerFunc(16, timer, 0);
}
if (key == ' ') {
calculateMetaballs();
needsRedisplay = true;
- needsReshading = true;
+ curBeenShaded = false;
+ }
+ if (key == '0') {
+ curMode = render;
+ needsRedisplay = true;
+ }
+ if (key == '1') {
+ curMode = debugContDist;
+ needsRedisplay = true;
+ }
+ if (key == '2') {
+ curMode = debugColor;
+ needsRedisplay = true;
+ }
+ if (key == '3') {
+ curMode = debugProbAct;
+ needsRedisplay = true;
+ }
+ if (key == '4') {
+ curMode = debugProbExt;
+ needsRedisplay = true;
}
- if (key == 'd') {
- debugContDist = !debugContDist;
+ if (key == 's') {
+ envColorIdx = (envColorIdx + 1) % envColors.size();
needsRedisplay = true;
+ curBeenShaded = false;
}
}
float dx = x - prevMouseX, dy = y - prevMouseY;
prevMouseX = x;
prevMouseY = y;
- const vec3 origin(0, 18, 0);
+ const vec3 origin(0, 0, 0);
const float sensitivity = 0.003f;
auto camMat = translate(mat4(1), origin + camPos);
auto rotation = rotate(rotate(mat4(1), -dx * sensitivity, {0, 1, 0}),
prevMouseY = y;
}
+void reshape(int w, int h) {
+ width = w;
+ height = h;
+}
+
int main(int argc, char **argv) {
glutInit(&argc, argv);
- glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGB |
+ glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA | GLUT_ALPHA |
GLUT_3_2_CORE_PROFILE);
glutInitWindowSize(width, height);
glutCreateWindow("Clouds");
glutDisplayFunc(display);
+ glutReshapeFunc(reshape);
+ glutKeyboardFunc(keyboard);
+ glutMotionFunc(motion);
+ glutPassiveMotionFunc(passiveMotion);
+ glutTimerFunc(16, timer, 0);
glewInit();
Program prog("billboardvert.glsl", "billboardfrag.glsl");
-
bbProg = prog.progId;
- glUseProgram(bbProg);
+ Program sProg("sunvert.glsl", "sunfrag.glsl");
+ sunProg = sProg.progId;
glGenVertexArrays(1, &bbVao);
+ glUseProgram(sunProg);
+ glBindVertexArray(bbVao);
+ glUseProgram(bbProg);
glBindVertexArray(bbVao);
GLuint vbos[2];
glGenBuffers(2, vbos);
initClouds(&cs);
calculateMetaballs();
- glGenTextures(1, &attenuationTex);
-
- glutKeyboardFunc(keyboard);
- glutMotionFunc(motion);
- glutPassiveMotionFunc(passiveMotion);
- glutTimerFunc(16, timer, 0);
-
- // set up billboard prog
+#ifdef PBO
+ // setup PBOs for buffering readPixels
+ glGenBuffers(numPbos, pboBufs);
+ for (int i = 0; i < numPbos; i++) {
+ glBindBuffer(GL_PIXEL_PACK_BUFFER, pboBufs[i]);
+ glBufferData(GL_PIXEL_PACK_BUFFER, 64 * 64 * 4, NULL,
+ GL_DYNAMIC_READ);
+ }
+ glBindBuffer(GL_PIXEL_PACK_BUFFER, 0);
+#endif
glutMainLoop();