loader lottie: added empty interface body

This marks the first step towards implementing the Lottie feature.

meson.build

@@ -49,6 +49,11 @@ if get_option('loaders').contains('webp_beta') == true
     config_h.set10('THORVG_WEBP_LOADER_SUPPORT', true)
 endif
 
+if get_option('loaders').contains('lottie_beta') == true
+    config_h.set10('THORVG_LOTTIE_LOADER_SUPPORT', true)
+endif
+
+
 #Savers
 all_savers = false
 
@@ -119,13 +124,14 @@ Summary:
     Loader (PNG):          @8@
     Loader (JPG):          @9@
     Loader (WEBP_BETA):    @10@
-    Saver (TVG):           @11@
-    CAPI Binding:          @12@
-    Log Message:           @13@
-    Tests:                 @14@
-    Examples:              @15@
-    Tool (Svg2Tvg):        @16@
-    Tool (Svg2Png):        @17@
+    Loader (LOTTIE_BETA):  @11@
+    Saver (TVG):           @12@
+    CAPI Binding:          @13@
+    Log Message:           @14@
+    Tests:                 @15@
+    Examples:              @16@
+    Tool (Svg2Tvg):        @17@
+    Tool (Svg2Png):        @18@
 
 '''.format(
         meson.project_version(),
@@ -139,6 +145,7 @@ Summary:
         all_loaders or get_option('loaders').contains('png'),
         all_loaders or get_option('loaders').contains('jpg'),
         get_option('loaders').contains('webp_beta'),
+        get_option('loaders').contains('lottie_beta'),
         all_savers or get_option('savers').contains('tvg'),
         get_option('bindings').contains('capi'),
         get_option('log'),

meson_options.txt

@@ -6,7 +6,7 @@ option('engines',
 
 option('loaders',
    type: 'array',
-   choices: ['', 'tvg', 'svg', 'png', 'jpg', 'webp_beta','all'],
+   choices: ['', 'tvg', 'svg', 'png', 'jpg', 'webp_beta', 'lottie_beta', 'all'],
    value: ['svg', 'tvg'],
    description: 'Enable File Loaders in thorvg ("all" does not include "*_beta".)')
 

src/loaders/lottie/meson.build

@@ -0,0 +1,9 @@
+source_file = [
+   'tvgLottieLoader.h',
+   'tvgLottieLoader.cpp',
+]
+
+subloader_dep += [declare_dependency(
+    include_directories : include_directories('.'),
+    sources : source_file
+)]

src/loaders/lottie/tvgLottieLoader.cpp

@@ -0,0 +1,294 @@
+/*
+ * Copyright (c) 2023 the ThorVG project. All rights reserved.
+
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <math.h>
+#include "tvgLoader.h"
+#include "tvgLottieLoader.h"
+
+/************************************************************************/
+/* Internal Class Implementation                                        */
+/************************************************************************/
+
+static bool _checkDotLottie(const char *str)
+{
+    //check the .Lottie signature.
+    if (str[0] == 0x50 && str[1] == 0x4B && str[2] == 0x03 && str[3] == 0x04) return true;
+    else return false;
+}
+
+
+static int _str2int(const char* str, int len)
+{
+    int ret = 0;
+    for(int i = 0; i < len; ++i) {
+        ret = ret * 10 + (str[i] - '0');
+    }
+    return ret;
+}
+
+
+static int _str2float(const char* str, int len)
+{
+    //strndup()
+    auto tmp = (char*)malloc(len + 1);
+    if (!tmp) return 0;
+    tmp[len] = '\0';
+    memcpy(tmp, str, len);
+
+    auto ret = strtof(tmp, nullptr);
+    free(tmp);
+    return lround(ret);
+}
+
+
+void LottieLoader::clear()
+{
+    //TODO: Clear all used resources
+    if (copy) free((char*)content);
+    size = 0;
+    content = nullptr;
+    copy = false;
+}
+
+
+/************************************************************************/
+/* External Class Implementation                                        */
+/************************************************************************/
+
+LottieLoader::LottieLoader()
+{
+}
+
+
+LottieLoader::~LottieLoader()
+{
+    close();
+}
+
+
+void LottieLoader::run(unsigned tid)
+{
+    /* TODO: Compose current frame of Lottie Scene tree
+       The result should be assigned to "this->root" */
+}
+
+
+bool LottieLoader::header()
+{
+    //Quickly validate the given Lottie file without parsing in order to get the animation info.
+    auto p = content;
+
+    uint32_t depth = 0;
+
+    while (*p != '\0') {
+        if (*p == '{') {
+            ++depth;
+            ++p;
+            continue;
+        }
+        if (*p == '}') {
+            --depth;
+            ++p;
+            continue;
+        }
+        if (depth != 1) {
+            ++p;
+            continue;
+        }
+        //version.
+        if (!strncmp(p, "\"v\":", 4)) {
+            p += 4;
+            continue;
+        }
+        //framerate
+        if (!strncmp(p, "\"fr\":", 5)) {
+            p += 5;
+            auto e = strstr(p, ",");
+            if (!e) e = strstr(p, "}");
+            frameRate = _str2float(p, e - p);
+            p = e;
+            continue;
+        }
+        //width
+        if (!strncmp(p, "\"w\":", 4)) {
+            p += 4;
+            auto e = strstr(p, ",");
+            if (!e) e = strstr(p, "}");
+            w = static_cast<float>(_str2int(p, e - p));
+            p = e;
+            continue;
+        }
+        //height
+        if (!strncmp(p, "\"h\":", 4)) {
+            p += 4;
+            auto e = strstr(p, ",");
+            if (!e) e = strstr(p, "}");
+            h = static_cast<float>(_str2int(p, e - p));
+            p = e;
+            continue;
+        }
+        ++p;
+    }
+    TVGLOG("LOTTIE", "info: fr = %d, size = %d x %d", frameRate, (int)w, (int)h);
+
+    return true;
+}
+
+
+bool LottieLoader::open(const char* data, uint32_t size, bool copy)
+{
+    clear();
+
+    //If the format is dotLottie
+    auto dotLottie = _checkDotLottie(data);
+    if (dotLottie) {
+        TVGLOG("LOTTIE", "Requested .Lottie Format, Not Supported yet.");
+        return false;
+    }
+
+    if (copy) {
+        content = (char*)malloc(size);
+        if (!content) return false;
+        memcpy((char*)content, data, size);
+    } else content = data;
+
+    this->size = size;
+    this->copy = copy;
+
+    return header();
+}
+
+
+bool LottieLoader::open(const string& path)
+{
+    clear();
+
+    auto f = fopen(path.c_str(), "r");
+    if (!f) return false;
+
+    fseek(f, 0, SEEK_END);
+
+    size = ftell(f);
+    if (size == 0) {
+        fclose(f);
+        return false;
+    }
+
+    auto content = (char*)(malloc(sizeof(char) * size + 1));
+    fseek(f, 0, SEEK_SET);
+    auto ret = fread(content, sizeof(char), size, f);
+    if (ret < size) {
+        fclose(f);
+        return false;
+    }
+    content[size] = '\0';
+
+    fclose(f);
+
+    //If the format is dotLottie
+    auto dotLottie = _checkDotLottie(content);
+    if (dotLottie) {
+        TVGLOG("LOTTIE", "Requested .Lottie Format, Not Supported yet.");
+        return false;
+    }
+
+    this->content = content;
+    this->copy = true;
+
+    return header();
+}
+
+
+bool LottieLoader::resize(Paint* paint, float w, float h)
+{
+    if (!paint) return false;
+
+    auto sx = w / this->w;
+    auto sy = h / this->h;
+    Matrix m = {sx, 0, 0, 0, sy, 0, 0, 0, 1};
+    paint->transform(m);
+
+    return true;
+}
+
+
+bool LottieLoader::read()
+{
+    if (!content || size == 0) return false;
+
+    //the loading has been already completed in header()
+    if (root) return true;
+
+    TaskScheduler::request(this);
+
+    return true;
+}
+
+
+bool LottieLoader::close()
+{
+    this->done();
+
+    clear();
+
+    return true;
+}
+
+
+unique_ptr<Paint> LottieLoader::paint()
+{
+    this->done();
+
+    return std::move(root);
+}
+
+
+bool LottieLoader::frame(uint32_t frameNo)
+{
+    this->done();
+
+    return true;
+}
+
+
+uint32_t LottieLoader::totalFrame()
+{
+    this->done();
+
+    return 0;
+}
+
+
+uint32_t LottieLoader::curFrame()
+{
+    this->done();
+
+    return frameNo;
+}
+
+
+float LottieLoader::duration()
+{
+    this->done();
+
+    return 0;
+}

src/loaders/lottie/tvgLottieLoader.h

@@ -27,12 +27,13 @@
 #include "tvgFrameModule.h"
 #include "tvgTaskScheduler.h"
 
-class LottieLoader : public LoadModule, public FrameModule, public Task
+class LottieLoader : public FrameModule, public Task
 {
 public:
-    string filePath;                    //lottie file path
     const char* content = nullptr;      //lottie file data
     uint32_t size = 0;                  //lottie data size
+    uint32_t frameRate;
+    uint32_t frameNo = 0;               //current frame number
 
     unique_ptr<Scene> root;             //current motion frame
 
@@ -50,13 +51,11 @@ public:
     bool close() override;
     unique_ptr<Paint> paint() override;
 
-    bool animatable() override { return true; }
-
     //Frame Controls
     bool frame(uint32_t frameNo) override;
     uint32_t totalFrame() override;
     uint32_t curFrame() override;
-    double duration() override;
+    float duration() override;
 
 private:
     bool header();

src/loaders/meson.build

@@ -8,6 +8,10 @@ if all_loaders or get_option('loaders').contains('svg') == true
     subdir('svg')
 endif
 
+if get_option('loaders').contains('lottie_beta') == true
+    subdir('lottie')
+endif
+
 if all_loaders or get_option('loaders').contains('png') == true
     if get_option('static') == true
         subdir('png')

src/loaders/svg/tvgSvgLoader.cpp

@@ -3682,6 +3682,5 @@ bool SvgLoader::close()
 unique_ptr<Paint> SvgLoader::paint()
 {
     this->done();
-    if (root) return std::move(root);
-    else return nullptr;
+    return std::move(root);
 }

src/loaders/tvg/tvgTvgLoader.cpp

@@ -228,6 +228,5 @@ void TvgLoader::run(unsigned tid)
 unique_ptr<Paint> TvgLoader::paint()
 {
     this->done();
-    if (root) return std::move(root);
-    return nullptr;
+    return std::move(root);
 }