create immediate mode animation for tsoding

nob.c

@@ -122,6 +122,7 @@ int main(int argc, char **argv)
     if (!build_plug_c(force, PLUGS_DIR"template/plug.c", BUILD_DIR"libtemplate.so")) return 1;
     if (!build_plug_c(force, PLUGS_DIR"squares/plug.c", BUILD_DIR"libsquare.so")) return 1;
     if (!build_plug_c(force, PLUGS_DIR"tsoding/plug.c", BUILD_DIR"libtsoding.so")) return 1;
+    if (!build_plug_c(force, PLUGS_DIR"imtsoding/plug.c", BUILD_DIR"libimtsoding.so")) return 1;
     if (!build_plug_c(force, PLUGS_DIR"bezier/plug.c", BUILD_DIR"libbezier.so")) return 1;
     if (!build_plug_cxx(force, PLUGS_DIR"cpp/plug.cpp", BUILD_DIR"libcpp.so")) return 1;
 

plugs/imtsoding/imanim.c

@@ -0,0 +1,68 @@
+
+
+float clipTime(AnimState *a, float duration) {
+    float timeSinceStart = a->currentTime - a->clipStartTime;
+    float animT = timeSinceStart / duration;
+    if(animT < 0) //before the clip requested
+        animT = 0.f;
+    if(animT > 1) //after the clip requested
+        animT = 1.f;
+
+    if(a->globEnd < (a->clipStartTime + duration))
+        a->globEnd = a->clipStartTime + duration;
+
+    return animT;
+}
+float prevClipTime(AnimState *a, float duration) {
+    float timeSinceStart = a->currentTime - a->deltaTime - a->clipStartTime;
+    float animT = timeSinceStart / duration;
+    if(animT < 0) //before the clip requested
+        animT = 0.f;
+    if(animT > 1) //after the clip requested
+        animT = 1.f;
+
+    if(a->globEnd < (a->clipStartTime + duration))
+        a->globEnd = a->clipStartTime + duration;
+
+    return animT;
+}
+
+void anim_wait(AnimState *a, float duration) {
+    if(a->globEnd < (a->clipStartTime + duration))
+        a->globEnd = a->clipStartTime + duration;
+    a->clipStartTime = a->globEnd;
+}
+
+void wait_for_end(AnimState *a){
+	a->clipStartTime = a->globEnd;
+}
+
+void anim_move_scalar(AnimState *anim, float *src, float dst, float duration)
+{
+    float t = clipTime(anim, duration);
+    if(t<=0.0f) return;
+    if(t>=1.0f) {
+        *src = dst; return;
+    }
+    *src = Lerp(*src, dst, t);
+}
+
+void anim_move_vec2(AnimState *anim, Vector2 *src, Vector2 dst, float duration)
+{
+    float t = clipTime(anim, duration);
+    if(t<=0.0f) return;
+    if(t>=1.0f) {
+        *src = dst; return;
+    }
+    *src = Vector2Lerp(*src, dst, t);
+}
+
+void anim_move_vec4(AnimState *anim, Vector4 *src, Vector4 dst, float duration)
+{
+    float t = clipTime(anim, duration);
+    if(t<=0.0f) return;
+    if(t>=1.0f) {
+        *src = dst; return;
+    }
+    *src = Vector4Lerp(*src, dst, t);
+}

plugs/imtsoding/imanim.h

@@ -0,0 +1,48 @@
+#include <raymath.h>
+
+typedef struct {
+    float currentTime; // time since start of the animation, increment with deltaTime every frame
+    float clipStartTime; // where the code is in the animation, only updated by a "wait" operation, reset every frame.
+    float globEnd; // when the animation ends, updated by clipTime, reset every frame.
+    float deltaTime;
+
+} AnimState;
+
+/*
+* returns a value between [0.0, 1.0] representing at which point 
+* the current time the animation is in.
+* a 0.0 return value represents that the current clip hasn't started yet 
+* a 1.0 return value represents that the current clip is fully finished
+* 
+* updates the globEnd value used in wait_for_end
+*/
+float clipTime(AnimState *a, float duration);
+
+/*
+* returns a value between [0.0, 1.0] representing at which point 
+* the time the animation was in last frame.
+*
+* updates the globEnd value used in wait_for_end
+*
+* this is useful for sound triggers
+*
+*     if(clipTime(anim, 0.1f) > 0 && prevClipTime(anim, 0.1f) == 0.0)
+*         p->env.play_sound(p->kick_sound, p->kick_wave);
+*/
+float prevClipTime(AnimState *a, float duration);
+
+/*
+* advances the clipStartTime 
+*/
+void anim_wait(AnimState *a, float duration) ;
+void wait_for_end(AnimState *a);
+
+/*
+* utilities for interpolating floats using clipTime(anim, duration)
+* 
+* if clipTime would return 0.0f it is a noop
+* if clipTime(anim, duration) would return 1.0f does `*src = dst;`
+*/
+void anim_move_scalar(AnimState *anim, float *src, float dst, float duration);
+void anim_move_vec2(AnimState *anim, Vector2 *src, Vector2 dst, float duration);
+void anim_move_vec4(AnimState *anim, Vector4 *src, Vector4 dst, float duration);

plugs/imtsoding/plug.c

@@ -0,0 +1,194 @@
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <raylib.h>
+#include <raymath.h>
+#include "env.h"
+#include "plug.h"
+#define NOB_STRIP_PREFIX
+#include "nob.h"
+#include "imanim.h"
+
+#define PLUG(name, ret, ...) ret name(__VA_ARGS__);
+LIST_OF_PLUGS
+#undef PLUG
+
+#define FONT_SIZE 68
+
+typedef struct {
+    size_t size;
+    Font font;
+    float radius;
+    float roundness;
+    float alpha;
+    float rotation;
+    AnimState anim;
+    Env env;
+    Sound kick_sound;
+    Wave kick_wave;
+    bool finished;
+} Plug;
+
+static Plug *p;
+
+static void load_assets(void)
+{
+    p->font = LoadFontEx("./assets/fonts/Vollkorn-Regular.ttf", FONT_SIZE, NULL, 0);
+    p->kick_wave = LoadWave("./assets/sounds/kick.wav");
+    p->kick_sound = LoadSoundFromWave(p->kick_wave);
+}
+
+static void unload_assets(void)
+{
+    UnloadFont(p->font);
+    UnloadSound(p->kick_sound);
+    UnloadWave(p->kick_wave);
+}
+
+
+#define co_tween(anim, duration, ...) co_tween_impl((anim), (duration), __VA_ARGS__, NULL)
+
+
+void co_tween_impl(AnimState *anim, float duration, ...)
+{
+    va_list args;
+    va_start(args, duration);
+    float interp;
+    float *x = va_arg(args, float*);
+    while (x != NULL) {
+        float a = va_arg(args, double);
+        float b = va_arg(args, double);
+        anim_move_scalar(anim, x, b, duration);
+        x = va_arg(args, float*);
+    }
+    va_end(args);
+    wait_for_end(anim);
+}
+
+void co_sleep(AnimState *anim, float duration)
+{
+    anim_wait(anim, duration) ;
+}
+
+void animation(AnimState *anim, void *data)
+{
+    UNUSED(data);
+
+    p->radius = 0;
+    p->roundness = 0;
+    p->alpha = 0;
+    p->rotation = 0;
+
+    float duration = 0.15f;
+    float sleep = 0.25f;
+    float curr = clipTime(anim, 0.1f);
+    float prev = prevClipTime(anim, 0.1f);
+    if(curr > 0 && prev == 0.0)
+        p->env.play_sound(p->kick_sound, p->kick_wave);
+    co_tween(anim, duration, &p->radius, 0.f, 1.f);
+    co_sleep(anim, sleep);
+    if(clipTime(anim, 0.1f) > 0 && prevClipTime(anim, 0.1f) == 0.0)
+        p->env.play_sound(p->kick_sound, p->kick_wave);
+    co_tween(anim, duration, &p->roundness, 0.f, 1.f);
+    co_sleep(anim, sleep);
+    if(clipTime(anim, 0.1f) > 0 && prevClipTime(anim, 0.1f) == 0.0)
+        p->env.play_sound(p->kick_sound, p->kick_wave);
+    co_tween(anim, duration,
+         &p->alpha,     0.f, 1.f,
+         &p->roundness, 1.f, 0.f,
+         &p->rotation,  0.f, 1.f);
+    co_sleep(anim, sleep);
+    if(clipTime(anim, 0.1f) > 0 && prevClipTime(anim, 0.1f) == 0.0)
+        p->env.play_sound(p->kick_sound, p->kick_wave);
+    co_tween(anim, duration, &p->radius, 1.f, 0.f);
+    co_sleep(anim, 2.0);
+}
+
+void plug_reset(void)
+{
+    p->anim.currentTime = 0.f;
+}
+
+void plug_init(void)
+{
+    p = malloc(sizeof(*p));
+    assert(p != NULL);
+    memset(p, 0, sizeof(*p));
+    p->size = sizeof(*p);
+
+
+    load_assets();
+    plug_reset();
+}
+
+void *plug_pre_reload(void)
+{
+    unload_assets();
+    return p;
+}
+
+void plug_post_reload(void *state)
+{
+    p = state;
+    if (p->size < sizeof(*p)) {
+        TraceLog(LOG_INFO, "Migrating plug state schema %zu bytes -> %zu bytes", p->size, sizeof(*p));
+        p = realloc(p, sizeof(*p));
+        p->size = sizeof(*p);
+    }
+
+    load_assets();
+}
+
+void plug_update(Env env)
+{
+    p->env = env;
+
+    p->anim.clipStartTime = 0;
+    p->anim.globEnd = 0;
+    p->anim.currentTime += env.delta_time;
+    p->anim.deltaTime = env.delta_time;
+
+    animation(&p->anim, NULL);
+
+    p->finished = p->anim.currentTime >= p->anim.clipStartTime;
+
+    Color background_color = GetColor(0x181818FF);
+    Color green_color      = GetColor(0x73C936FF);
+    Color red_color        = GetColor(0xF43841FF);
+
+    ClearBackground(background_color);
+
+    Camera2D camera = {
+        .zoom = 1.0,
+        .rotation = 45.*p->rotation,
+        .offset = {env.screen_width/2, env.screen_height/2},
+    };
+
+    BeginMode2D(camera); {
+        float size = 300*p->radius;
+        Rectangle rec = {
+            .x          = -size/2,
+            .y          = -size/2,
+            .width      = size,
+            .height     = size,
+        };
+
+
+        // // Square
+        Color color = ColorAlphaBlend(green_color, ColorAlpha(red_color, p->alpha), WHITE);
+        DrawRectangleRounded(rec, p->roundness, 30, color);
+
+        // const char *text = "Tsoding Animation";
+        // Vector2 text_size = MeasureTextEx(p->font, text, FONT_SIZE, 0);
+        // Vector2 position = Vector2Scale(text_size, -0.5);
+        // DrawTextEx(p->font, text, position, FONT_SIZE, 0, foreground_color);
+    } EndMode2D();
+}
+
+bool plug_finished(void)
+{
+    return p->finished;
+}
+
+#include "imanim.c"