fix: proper initialization sequence

Author: stergiotis

skia/main/sdl3/app.cpp

@@ -999,7 +999,7 @@ int App::Run(CliOptions &opts) {
         createContext(clearColor, dm->w, dm->h);
     }
 
-    build_ImFontAtlas(*io.Fonts, fFontPaint);
+    //build_ImFontAtlas(*io.Fonts, fFontPaint);
 
     if(headless) {
         return mainLoopHeadless(opts, clearColor);

skia2/imzero_client_skia_sdl3_impl/imzero_client_skia_sdl3_app.cpp

@@ -622,13 +622,17 @@ static void printColorMode(FILE *fd) {
 }
 
 void ImZeroClient::App::setup(ImZeroCliOptions &opts) {
+    fApp.setup(opts.fBaseOptions); // will set up imgui, needed in render_init
+
     printColorMode(stderr);
     // prevent SIGPIPE when writing frames or reading user interaction events
     //signal(SIGPIPE, SIG_IGN);
 
     sk_sp<SkTypeface> typeface = nullptr;
     sk_sp<SkData> ttfData = nullptr;
     {
+        fFffiInFile = stdin;
+        fFffiOutFile = stdout;
         // setup skia/imgui shared objects
         if (opts.fFffiInterpreter) {
             if (opts.fFffiInFile != nullptr) {
@@ -650,25 +654,25 @@ void ImZeroClient::App::setup(ImZeroCliOptions &opts) {
         }
     }
     fFffiInterpreter = opts.fFffiInterpreter;
+}
+void ImZeroClient::App::completeFontSetup() {
     if (fFffiInterpreter) {
-        //render_init(fffiInFile, fffiOutFile);
+        render_init(fFffiInFile, fFffiOutFile);
+        // this assumes that the font setup commands will be sent in the first batch before (not evaluated in a frame context)
+        interpretCommands();
     }
-    fApp.setup(opts.fBaseOptions);
+    fApp.completeFontSetup();
 }
+
 SkSurface* ImZeroClient::App::preRender(bool& done, int& width, int& height) {
    return fApp.preRender(done, width, height);
 }
 void ImZeroClient::App::postRender(ImGuiSkia::FrameExportFormatE frameExportFormat, SkSurface* surface, int width, int height) {
     return fApp.postRender(frameExportFormat, surface, width, height);
 }
 ImGuiSkia::FrameExportFormatE ImZeroClient::App::render(SkSurface* surface, int width, int height) {
-    static bool first = true;
     auto const r = fApp.render(surface, width, height);
     if (fFffiInterpreter) {
-        if (first) {
-            first = false;
-            render_init(fFffiInFile, fFffiOutFile);
-        }
         render_render();
     }
     return r;

skia2/imzero_client_skia_sdl3_impl/imzero_client_skia_sdl3_app.h

@@ -41,6 +41,7 @@ namespace ImZeroClient
         void postPaint(SkSurface* surface, ImGuiSkia::FrameExportFormatE frameExportFormat, int width, int height);
 
         void setup(ImZeroCliOptions &opts);
+        void completeFontSetup();
         int mainLoop();
         void cleanup();
     private:

skia2/imzero_client_skia_sdl3_impl/main.cpp

@@ -60,6 +60,7 @@ int main(const int argc, const char** argv) {
 
     ImZeroClient::App app{};
     app.setup(opts);
+    app.completeFontSetup();
 
     const int r = app.mainLoop();
     app.cleanup();

skia2/stacktrace.sh

@@ -4,4 +4,4 @@ here=$(dirname "$(readlink -f "$BASH_SOURCE")")
 cd "$here"
 rm -f core
 coredumpctl -1 dump --output core
-gdb ./imgui_skia_exe core
+gdb ./bin/imgui_skia_exe core

skia_minimal/example_sdl3/main.cpp

@@ -12,6 +12,7 @@ int main(int argc, const char** argv) {
 
     ImGuiSkia::Driver::App app{};
     app.setup(opts);
+    app.completeFontSetup();
     const int r = app.mainLoop();
     app.cleanup();
     return r;

skia_minimal/imgui_skia_driver_impl/imgui_skia_app_sdl3.cpp

@@ -218,20 +218,6 @@ void ImGuiSkia::Driver::App::postPaint(SkSurface *surface, FrameExportFormatE fr
 
     FrameMark;
 }
-static void build_ImFontAtlas(ImFontAtlas& atlas, SkPaint& fontPaint) {
-    int w, h;
-    unsigned char* pixels;
-    atlas.GetTexDataAsAlpha8(&pixels, &w, &h);
-    SkImageInfo info = SkImageInfo::MakeA8(w, h);
-    const SkPixmap pmap(info, pixels, info.minRowBytes());
-    const SkMatrix localMatrix = SkMatrix::Scale(1.0f / static_cast<float>(w), 1.0f / static_cast<float>(h));
-    const auto fontImage = SkImages::RasterFromPixmap(pmap, nullptr, nullptr);
-    const auto fontShader = fontImage->makeShader(SkSamplingOptions(SkFilterMode::kLinear), localMatrix);
-    fontPaint.setShader(fontShader);
-    fontPaint.setColor(SK_ColorWHITE);
-    const ImTextureID texId = reinterpret_cast<intptr_t>(&fontPaint);
-    atlas.TexID = texId;
-}
 
 void ImGuiSkia::Driver::App::setup(CliOptions &opts) {
     // prevent SIGPIPE when writing frames or reading user interaction events
@@ -443,10 +429,24 @@ void ImGuiSkia::Driver::App::setup(CliOptions &opts) {
         }
     }
 
-
     createContext(initialWindowWidth, initialWindowHeight);
-    build_ImFontAtlas(*((ImGui::GetIO()).Fonts), fFontPaint);
 }
+void ImGuiSkia::Driver::App::completeFontSetup() {
+    ImFontAtlas &atlas = *((ImGui::GetIO()).Fonts);
+    int w, h;
+    unsigned char* pixels;
+    atlas.GetTexDataAsAlpha8(&pixels, &w, &h);
+    const SkImageInfo info = SkImageInfo::MakeA8(w, h);
+    const SkPixmap pmap(info, pixels, info.minRowBytes());
+    const SkMatrix localMatrix = SkMatrix::Scale(1.0f / static_cast<float>(w), 1.0f / static_cast<float>(h));
+    const auto fontImage = SkImages::RasterFromPixmap(pmap, nullptr, nullptr);
+    const auto fontShader = fontImage->makeShader(SkSamplingOptions(SkFilterMode::kLinear), localMatrix);
+    fFontPaint.setShader(fontShader);
+    fFontPaint.setColor(SK_ColorWHITE);
+    const ImTextureID texId = reinterpret_cast<intptr_t>(&fFontPaint);
+    atlas.TexID = texId;
+}
+
 SkSurface * ImGuiSkia::Driver::App::preRender(bool &done, int &width, int &height) {
     const ImGuiIO &io = ImGui::GetIO();
     width = static_cast<int>(io.DisplaySize.x);

skia_minimal/imgui_skia_driver_impl/imgui_skia_app_sdl3.h

@@ -20,6 +20,7 @@ namespace ImGuiSkia::Driver {
         void postPaint(SkSurface* surface, FrameExportFormatE frameExportFormat, int width, int height);
 
         void setup(CliOptions &opts);
+        void completeFontSetup();
         int mainLoop();
         void cleanup();
 

skia_minimal/imgui_skia_impl/imgui_skia_hooks_impl.h

@@ -1,7 +1,6 @@
 #pragma once
 
 #include "imgui_skia_config.h"
-#include "include/core/SkFont.h"
 #include "imgui_skia_paragraph.h"
 
 // NOTE: part of ImDrawChannel as std::vector and FlatBufferBuilder are not trivially default constructible