X-Git-Url: https://git.lukelau.me/?p=clouds.git;a=blobdiff_plain;f=clouds.cpp;h=b8ea3f0071cb0f0e5ce34bdfd48e44b17151edbd;hp=96612e8f1db71c7eef35b9d298ccc46e0bfc3caa;hb=HEAD;hpb=31f19438c73b207f506ba0b1187d2de75c166a5b diff --git a/clouds.cpp b/clouds.cpp index 96612e8..b8ea3f0 100644 --- a/clouds.cpp +++ b/clouds.cpp @@ -1,67 +1,36 @@ +#include "GL/glew.h" #include "debug.hpp" #include "program.hpp" -#include +#include "simulation.hpp" #include +#include +#include #include #include #include #include #include +#include #include #pragma clang diagnostic ignored "-Wdeprecated-declarations" +enum Mode { render, debugContDist, debugColor, debugProbExt, debugProbAct }; +Mode curMode = render; + using namespace std; using namespace glm; -static const int CLOUD_DIM = 16; -struct Clouds { - char cld[CLOUD_DIM][CLOUD_DIM][CLOUD_DIM]; - float contDist[CLOUD_DIM][CLOUD_DIM][CLOUD_DIM]; -}; - -// 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) { - if (r > metaballR) +const float metaballR = 1.f / 16.f; +inline float metaballField(float r) { + 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; */ - -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; void checkError() { if (GLenum e = glGetError()) { @@ -70,58 +39,104 @@ void checkError() { } } -vector bbColors; - -GLuint bbProg; +GLuint bbProg, sunProg; GLuint bbVao; -void calculateMetaballs() {} - // Here we need to generate n_q textures for different densities of metaballs // 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, 0.3f + 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 - + fmin(1, (3 * 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]); - checkError(); + glBindTexture(GL_TEXTURE_2D, bbTexIds[d]); 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; + ivec3 coords; + /** Density */ + float d; + vec4 col; }; -// TODO: why is the x axis flipped?? -/* vector metaballs = {{{-0.5, 0.5, 0.5}, 0.25}, */ -/* {{-0.3, 0.5, 0.3}, 0.25}}; */ -vector metaballs = {{{0, 0, 0.5}, 1.f}, - {{0, 0.3, 0.3}, 0.7f}}; -vec3 sunPos = {0, 2, 2}, viewPos = {0, 0, 0}, lookPos = {0, 0, 1}; +array metaballs; + +const float cloudScale = metaballR; +const float metaballScale = metaballR * 1.5f; +Clouds cs; + +void calculateMetaballs() { + 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); */ + /* } */ + 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]; + /* 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, 5, 0}, sunDir = {0, -1, 0}; +size_t envColorIdx = 0; +// First color is sun color, second is sky color +std::array, 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"); @@ -133,7 +148,7 @@ void setProjectionAndViewUniforms(GLuint progId) { /** Orientates the transformation matrix to face the camera in the view matrix */ -void faceView(mat4 m) { +mat4 faceView(mat4 m) { m[0][0] = view[0][0]; m[0][1] = view[1][0]; m[0][2] = view[2][0]; @@ -143,13 +158,39 @@ void faceView(mat4 m) { m[2][0] = view[0][2]; m[2][1] = view[1][2]; m[2][2] = view[2][2]; + return m; } -GLuint attenuationTex; +#define PBO -void shadeClouds() { +/* 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]; - bbColors.clear(); + // 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 @@ -162,17 +203,28 @@ void shadeClouds() { }); glActiveTexture(GL_TEXTURE0); - glBindTexture(GL_TEXTURE_2D, bbTexIds[0]); glUniform1i(glGetUniformLocation(bbProg, "tex"), 0); GLuint modelLoc = glGetUniformLocation(bbProg, "model"); + glUniform1i(glGetUniformLocation(bbProg, "debug"), 0); - for (auto k : metaballs) { + 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 - faceView(model); + model = faceView(model); + + model = scale(model, vec3(metaballScale)); glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model)); @@ -185,6 +237,8 @@ void shadeClouds() { // 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. @@ -194,81 +248,169 @@ void shadeClouds() { // 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); + ivec2 screenPos = + ((vec2(proj * view * model * vec4(0, 0, 0, 1)) + vec2(1)) / vec2(2)) * + vec2(shadeWidth, shadeHeight); + +#ifndef PBO vec4 pixel; - glReadPixels(screenPos.x, screenPos.y, 1, 1, GL_RGBA, GL_FLOAT, value_ptr(pixel)); + // TODO: This is a huge bottleneck + 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. - bbColors.push_back(pixel); + 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>(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(viewPos, a.pos) > distance(viewPos, b.pos); + return distance(camPos, a.pos) > distance(camPos, b.pos); }); + 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); + for (int i = 0; i < metaballs.size(); i++) { Metaball k = metaballs[i]; 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. - faceView(model); + model = faceView(model); + + model = scale(model, vec3(metaballScale)); 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].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 - 1); + glBindTexture(GL_TEXTURE_2D, bbTexIds[dIdx]); // Don't modulate it -- blend it glUniform1i(glGetUniformLocation(bbProg, "modulate"), 0); + 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)); + } + // Render the billboard with the blending function. glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0); } } +bool curBeenShaded = false; + void display() { - view = glm::lookAt(sunPos, viewPos, {0, 1, 0}); - proj = glm::ortho(1.f * aspect, -1.f * aspect, -1.f, 1.f, znear, zfar); + if (!curBeenShaded && (curMode == render || curMode == debugColor)) { + // TODO: find a way to make sure there's no clipping + 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(); + curBeenShaded = true; + } - view = glm::lookAt(viewPos, lookPos, {0, 1, 0}); - proj = glm::perspective(60.f, aspect, znear, zfar); + 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(0.73,1,1,1); // 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(); @@ -276,22 +418,103 @@ void display() { glutSwapBuffers(); } +bool needsRedisplay = false; +void timer(int _) { + if (needsRedisplay) { + glutPostRedisplay(); + } + needsRedisplay = false; + glutTimerFunc(16, timer, 0); +} + +void keyboard(unsigned char key, int x, int y) { + if (key == ' ') { + calculateMetaballs(); + needsRedisplay = 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 == 's') { + envColorIdx = (envColorIdx + 1) % envColors.size(); + needsRedisplay = true; + curBeenShaded = false; + } +} + +int prevMouseX, prevMouseY; +bool firstMouse = true; +void motion(int x, int y) { + if (firstMouse) { + prevMouseX = x; + prevMouseY = y; + firstMouse = false; + } + float dx = x - prevMouseX, dy = y - prevMouseY; + prevMouseX = x; + prevMouseY = y; + 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}), + -dy * sensitivity, {1, 0, 0}); + auto rotAroundOrig = camMat * rotation * translate(mat4(1), origin - camPos); + camPos = rotAroundOrig * glm::vec4(camPos, 0); + needsRedisplay = true; +} + +void passiveMotion(int x, int y) { + prevMouseX = x; + 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); @@ -314,13 +537,19 @@ int main(int argc, char **argv) { precalculateBillboardTextures(); + initClouds(&cs); calculateMetaballs(); - glGenTextures(1, &attenuationTex); - - /* 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();