X-Git-Url: https://git.lukelau.me/?p=clouds.git;a=blobdiff_plain;f=clouds.cpp;h=b8ea3f0071cb0f0e5ce34bdfd48e44b17151edbd;hp=f6c0083837e15611cc628e5316e3c55fd63cd4d5;hb=HEAD;hpb=724a80cbecb587d1d069f7999758181b10d92f73 diff --git a/clouds.cpp b/clouds.cpp index f6c0083..b8ea3f0 100644 --- a/clouds.cpp +++ b/clouds.cpp @@ -1,13 +1,13 @@ +#include "GL/glew.h" #include "debug.hpp" #include "program.hpp" -#include "simulation.h" -#include +#include "simulation.hpp" #include #include +#include #include #include #include -#include #include #include #include @@ -63,7 +63,8 @@ void precalculateBillboardTextures() { float r = distance(vec2(i, j), vec2(16, 16)) / 16; float density = (float)d / NQ; data[i + j * 32] = - 1 - (3 * density * 0.7 * (metaballField(r) / normalizationFactor)); + 1 - + fmin(1, (3 * density * (metaballField(r) / normalizationFactor))); } } @@ -93,7 +94,7 @@ struct Metaball { array metaballs; const float cloudScale = metaballR; -const float metaballScale = metaballR * 3.f; +const float metaballScale = metaballR * 1.5f; Clouds cs; void calculateMetaballs() { @@ -123,7 +124,7 @@ void calculateMetaballs() { */ } -vec3 sunPos = {0, 10, 0}, sunDir = {0, -1, 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, 3> envColors{ @@ -134,8 +135,8 @@ 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 = 512, height = 512; -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"); @@ -160,13 +161,37 @@ mat4 faceView(mat4 m) { return m; } +#define PBO + +/* const int shadeWidth = 256, shadeHeight = 256; */ +const int shadeWidth = 256, shadeHeight = 256; + #ifdef PBO -const int numPbos = 64; +const int numPbos = 512; GLuint pboBufs[numPbos]; -GLbyte sink[1000 * 1000 * 4]; +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); @@ -183,7 +208,7 @@ void shadeClouds() { GLuint modelLoc = glGetUniformLocation(bbProg, "model"); glUniform1i(glGetUniformLocation(bbProg, "debug"), 0); - /* glViewport(0, 0, shadeWidth, shadeHeight); */ + glViewport(0, 0, shadeWidth, shadeHeight); #ifdef PBO int pboIdx = 0; @@ -192,7 +217,7 @@ void shadeClouds() { 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()); + /* fprintf(stderr, "\rShading metaball %lu/%lu...", i, metaballs.size()); */ // place the billboard at the center of k mat4 model = translate(mat4(1), k.pos); @@ -225,48 +250,56 @@ void shadeClouds() { // 3. Multiply by (width * height) ivec2 screenPos = ((vec2(proj * view * model * vec4(0, 0, 0, 1)) + vec2(1)) / vec2(2)) * - vec2(width, height); - vec4 pixel; + vec2(shadeWidth, shadeHeight); #ifndef PBO + vec4 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. + 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]); - glReadPixels(0, 0, width, height, GL_RGBA, GL_UNSIGNED_BYTE, - NULL); + // 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); - glBindBuffer(GL_PIXEL_PACK_BUFFER, pboBufs[(pboIdx + 1) % numPbos]); - GLuint offset = screenPos.x * 4 + screenPos.y * (int)width * 4; - ivec4 *src = (ivec4 *)glMapBufferRange(GL_PIXEL_PACK_BUFFER, offset, 4, GL_MAP_READ_BIT); - checkError(); - if (src) { - ivec4 t = src[(int)screenPos.x + (int)screenPos.y * (int)width]; - pixel = vec4(t) / vec4(255.f); + int nextPbo = (pboIdx + 1) % numPbos; + if (i >= numPbos - 1) { + // start mapping the read values back + mapPixelRead(nextPbo, i - numPbos + 1); } - glUnmapBuffer(GL_PIXEL_PACK_BUFFER); - - pboIdx = (pboIdx + 1) % numPbos; - - glBindBuffer(GL_PIXEL_PACK_BUFFER, 0); + pboIdx = nextPbo; #endif - // Multiply the pixel value by the sunlight color. - pixel *= envColors[envColorIdx][0]; + i++; + } + /* fprintf(stderr, "\n"); */ - // Store the color into an array C[k] as the color of the billboard. - k.col = pixel; +#ifdef PBO + // sink remaining reads + for (int i = 0; i < numPbos; i++) { + mapPixelRead(i, metaballs.size() - numPbos + i); } - fprintf(stderr, "\n"); +#endif auto elapsed = std::chrono::system_clock::now() - begin_time; - double elapsed_seconds = std::chrono::duration_cast >(elapsed).count(); - fprintf(stderr, "time with pbo: %f\n", elapsed_seconds); + 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); */ + glViewport(0, 0, width, height); } void renderObject() { @@ -274,7 +307,7 @@ void renderObject() { // render the sun glUseProgram(sunProg); mat4 model = translate(mat4(1), sunPos); - /* model = lookAt(sunPos, sunPos + sunDir, {0, 1, 0}) * model; */ + 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)); @@ -341,7 +374,7 @@ void renderClouds() { 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(0.2)); + model = scale(model, vec3(0.1)); glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model)); } @@ -350,9 +383,10 @@ void renderClouds() { } } -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(100.f), sunPos, {0, 0, 1}); // TODO: calculate bounds so everything is covered @@ -363,10 +397,11 @@ void display() { 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); @@ -385,7 +420,6 @@ void display() { bool needsRedisplay = false; void timer(int _) { - /* calculateMetaballs(); */ if (needsRedisplay) { glutPostRedisplay(); } @@ -397,10 +431,9 @@ void keyboard(unsigned char key, int x, int y) { if (key == ' ') { calculateMetaballs(); needsRedisplay = true; - needsReshading = curMode == render; + curBeenShaded = false; } if (key == '0') { - needsReshading = curMode != render; curMode = render; needsRedisplay = true; } @@ -423,7 +456,7 @@ void keyboard(unsigned char key, int x, int y) { if (key == 's') { envColorIdx = (envColorIdx + 1) % envColors.size(); needsRedisplay = true; - needsReshading = true; + curBeenShaded = false; } } @@ -453,6 +486,11 @@ void passiveMotion(int x, int y) { 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_RGBA | GLUT_ALPHA | @@ -460,6 +498,11 @@ int main(int argc, char **argv) { glutInitWindowSize(width, height); glutCreateWindow("Clouds"); glutDisplayFunc(display); + glutReshapeFunc(reshape); + glutKeyboardFunc(keyboard); + glutMotionFunc(motion); + glutPassiveMotionFunc(passiveMotion); + glutTimerFunc(16, timer, 0); glewInit(); @@ -497,17 +540,12 @@ int main(int argc, char **argv) { initClouds(&cs); calculateMetaballs(); - glutKeyboardFunc(keyboard); - glutMotionFunc(motion); - glutPassiveMotionFunc(passiveMotion); - glutTimerFunc(16, timer, 0); - #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, width * height * 4, NULL, + glBufferData(GL_PIXEL_PACK_BUFFER, 64 * 64 * 4, NULL, GL_DYNAMIC_READ); } glBindBuffer(GL_PIXEL_PACK_BUFFER, 0);