From 5d3ff36045bfb11af0f373d5ecee7c9b54e4c4f9 Mon Sep 17 00:00:00 2001 From: mattkae Date: Mon, 3 Apr 2023 06:35:27 -0400 Subject: Folderized all of the seasons and loading the shaders from a remote source --- themes/src/winter/Snowflake.cpp | 189 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 189 insertions(+) create mode 100644 themes/src/winter/Snowflake.cpp (limited to 'themes/src/winter/Snowflake.cpp') diff --git a/themes/src/winter/Snowflake.cpp b/themes/src/winter/Snowflake.cpp new file mode 100644 index 0000000..57f1a8f --- /dev/null +++ b/themes/src/winter/Snowflake.cpp @@ -0,0 +1,189 @@ +#include "Snowflake.h" +#include "../Renderer2d.h" +#include "../mathlib.h" +#include "../list.h" +#include + +/* + + What else to do? + + - Windstream that blows a certain selection of snowflakes in a loop-dee-loop pattern + - Snowflakes that land on the ground and melt + - Snowflakes that spin along the Y-axis for a three dimensional effect + + */ + +const Vector4 snowColor = Vector4(1.0, 0.98, 0.98, 1); +const Vector2 NUM_ARMS_RANGE = Vector2(6.f, 8.f); +const Vector2 RADIUS_RANGE = Vector2(8.f, 32.f); +const Vector2 VELOCITY_RANGE_X = Vector2(-10.f, 10.f); +const Vector2 VELOCITY_RANGE_Y = Vector2(-100.f, -85.f); +const Vector2 ROTATION_VELOCITY_RANGE = Vector2(-PI / 8.f, PI / 8.f); +const Vector2 WIND_VELOCITY_RANGE_X = Vector2(-3.f, 3.f); +const Vector2 WIND_VELOCITY_RANGE_Y = Vector2(3.f, 10.f); +const f32 GRAVITY = 5.f; + +inline void generateSnowflakeArm(f32 width, f32 height, f32 angle, matte::List* vertices, Mat4x4 transform = Mat4x4()) { + f32 halfWidth = width / 2.f; + Vector2 leftStart = transform * Vector2(-halfWidth, 0).rotate(angle); + Vector2 leftEnd = transform * Vector2(-halfWidth, height).rotate(angle); + Vector2 rightStart = transform * Vector2(halfWidth, 0).rotate(angle); + Vector2 rightEnd = transform * Vector2(halfWidth, height).rotate(angle); + + vertices->add({ leftStart, snowColor, Mat4x4() }); + vertices->add({ leftEnd, snowColor, Mat4x4() }); + vertices->add({ rightEnd, snowColor, Mat4x4() }); + vertices->add({ leftStart, snowColor, Mat4x4() }); + vertices->add({ rightEnd, snowColor, Mat4x4() }); + vertices->add({ rightStart, snowColor, Mat4x4() }); +} + +/** + Fills in the vertices array vertices that represent a snowflake shape. The snowflake shape consists + of numArms jutting out of the center radially. The center of the flake is connected. The radius is + used to determine the length of the arms. The first third of each arm is barren, after which branches + extends on either side of the arm at an angle of about 60 degrees. Each branch can itself have tiny + sub branches jutting out of it, but these should be not nearly as large as the regular branches. + + With all of this in mind, we should be able to build a convincing snowflake. + + :param vertices List of vertices to be filled in + :param numArms Number of arms radially sticking out of the snowflake + :param radius Length of the snowflake arms + */ +inline void generateSnowflakeShape(matte::List* vertices, i32 numArms, f32 radius, f32 armWidthRatio = 0.08f) { + f32 innerRadius = 0; + f32 outerRadius = 2 * radius; + f32 dx = ((2 * PI) / numArms); + for (i32 armIndex = 0; armIndex < numArms; armIndex++) { + f32 armAngle = dx * armIndex; + generateSnowflakeArm(armWidthRatio * radius, radius, armAngle, vertices); + f32 armLeftAngle = DEG_TO_RAD(60.f); + f32 armRightAngle = DEG_TO_RAD(-60.f); + + const i32 NUM_SUB_ARMS = 4; + for (i32 subArmIndex = 0; subArmIndex < NUM_SUB_ARMS; subArmIndex++) { + f32 height = (radius / static_cast(subArmIndex)); + f32 width = (armWidthRatio / (subArmIndex + 1)) * height; + f32 transY = (radius / (NUM_SUB_ARMS + 1)) * (subArmIndex + 1); + Vector2 translation = Vector2(0, transY).rotate(armAngle); + generateSnowflakeArm(width, height, armAngle, vertices, Mat4x4().translateByVec2(translation).rotate2D(armLeftAngle)); + generateSnowflakeArm(width, height, armAngle, vertices, Mat4x4().translateByVec2(translation).rotate2D(armRightAngle)); + } + } +} + +inline void initFlake(SnowflakeParticleRenderer* renderer, SnowflakeUpdateData* ud) { + ud->radius = randomFloatBetween(RADIUS_RANGE.x, RADIUS_RANGE.y); + ud->vtxIdx = renderer->vertices.numElements; + generateSnowflakeShape(&renderer->vertices, + randomFloatBetween(NUM_ARMS_RANGE.x, NUM_ARMS_RANGE.y), + ud->radius); + + ud->numVertices = renderer->vertices.numElements - ud->vtxIdx; + ud->velocity = Vector2(randomFloatBetween(VELOCITY_RANGE_X.x, VELOCITY_RANGE_X.y), randomFloatBetween(VELOCITY_RANGE_Y.x, VELOCITY_RANGE_Y.y)); + ud->position = Vector2(randomFloatBetween(0, renderer->xMax), randomFloatBetween(renderer->yMax, 4 * renderer->yMax)); + ud->rotateVelocity = randomFloatBetween(ROTATION_VELOCITY_RANGE.x, ROTATION_VELOCITY_RANGE.y); +} + +void SnowflakeParticleRenderer::load(SnowflakeLoadParameters params, Renderer2d* renderer) { + numSnowflakes = params.numSnowflakes; + + updateData = new SnowflakeUpdateData[params.numSnowflakes]; + + xMax = static_cast(renderer->context->width); + yMax = static_cast(renderer->context->height); + + vertices.deallocate(); + vertices.growDynamically = true; + + // Initialize each snow flake with its shape + for (i32 s = 0; s < numSnowflakes; s++) { + auto ud = &updateData[s]; + initFlake(this, ud); + } + + useShader(renderer->shader); + + glGenVertexArrays(1, &vao); + glBindVertexArray(vao); + + glGenBuffers(1, &vbo); + glBindBuffer(GL_ARRAY_BUFFER, vbo); + glBufferData(GL_ARRAY_BUFFER, vertices.numElements * sizeof(Vertex2D), &vertices.data[0], GL_DYNAMIC_DRAW); + + glEnableVertexAttribArray(renderer->attributes.position); + glVertexAttribPointer(renderer->attributes.position, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex2D), (GLvoid *)0); + + glEnableVertexAttribArray(renderer->attributes.color); + glVertexAttribPointer(renderer->attributes.color, 4, GL_FLOAT, GL_FALSE, sizeof(Vertex2D), (GLvoid *)offsetof(Vertex2D, color)); + + for (i32 idx = 0; idx < 4; idx++) { + i32 offset = (4 * sizeof(f32)) * idx; + glEnableVertexAttribArray(renderer->attributes.vMatrix + idx); + glVertexAttribPointer(renderer->attributes.vMatrix + idx, + 4, + GL_FLOAT, + GL_FALSE, + sizeof(Vertex2D), + (GLvoid *)(offsetof(Vertex2D, vMatrix) + offset)); + } + + glBindBuffer(GL_ARRAY_BUFFER, 0); + glBindVertexArray(0); +} + +inline void resetFlake(SnowflakeParticleRenderer* renderer, SnowflakeUpdateData* ud) { + ud->position.y = 2 * renderer->yMax; + ud->velocity = Vector2(randomFloatBetween(-10, 10), randomFloatBetween(-100, -85)); + ud->rotation = 0; +} + +inline void updateFlake(SnowflakeParticleRenderer* renderer, SnowflakeUpdateData* ud, i32 s, f32 dtSeconds) { + ud->velocity = ud->velocity + Vector2(0, -(GRAVITY * dtSeconds)); + //if (addWind) ud->velocity += renderer->windSpeed; + ud->position += ud->velocity * dtSeconds; + ud->rotation += ud->rotateVelocity * dtSeconds; + + Mat4x4 m = Mat4x4().translateByVec2(ud->position).rotate2D(ud->rotation); + for (i32 v = ud->vtxIdx; v < (ud->vtxIdx + ud->numVertices); v++) { + renderer->vertices.data[v].vMatrix = m; + } + + if (ud->position.y <= -ud->radius) { + resetFlake(renderer, ud); + } +} + +void SnowflakeParticleRenderer::update(f32 dtSeconds) { + timeUntilNextWindSeconds -= dtSeconds; + if (timeUntilNextWindSeconds < 0) { + timeUntilNextWindSeconds = randomFloatBetween(2.5f, 10.f); + } + + for (i32 s = 0; s < numSnowflakes; s++) { + SnowflakeUpdateData* ud = &updateData[s]; + updateFlake(this, ud, s, dtSeconds); + } +} + +void SnowflakeParticleRenderer::render(Renderer2d* renderer) { + setShaderMat4(renderer->uniforms.model, model); + + glBindBuffer(GL_ARRAY_BUFFER, vbo); + glBufferSubData(GL_ARRAY_BUFFER, 0, vertices.numElements * sizeof(Vertex2D), &vertices.data[0]); + + glBindVertexArray(vao); + glDrawArrays(GL_TRIANGLES, 0, vertices.numElements); + glBindVertexArray(0); +} + +void SnowflakeParticleRenderer::unload() { + glDeleteVertexArrays(1, &vao); + glDeleteBuffers(1, &vbo); + vao = 0; + vbo = 0; + vertices.deallocate(); + delete [] updateData; +} -- cgit v1.2.1