add font demo

Makefile

@@ -40,6 +40,7 @@ dirs:
 	${MAKE} -C src/nanovg/ ${MAKEFLAGS} CXX=${CXX} ${MAKECMDGOALS}
 	${MAKE} -C src/optflow/ ${MAKEFLAGS} CXX=${CXX} ${MAKECMDGOALS}
 	${MAKE} -C src/beauty/ ${MAKEFLAGS} CXX=${CXX} ${MAKECMDGOALS}
+	${MAKE} -C src/font/ ${MAKEFLAGS} CXX=${CXX} ${MAKECMDGOALS}
 
 debian-release:
 	${MAKE} -C src/tetra/ ${MAKEFLAGS} CXX=${CXX} release
@@ -47,6 +48,7 @@ debian-release:
 	${MAKE} -C src/nanovg/ ${MAKEFLAGS} CXX=${CXX} release
 	${MAKE} -C src/optflow/ ${MAKEFLAGS} CXX=${CXX} release
 	${MAKE} -C src/beauty/ ${MAKEFLAGS} CXX=${CXX} release
+	${MAKE} -C src/font/ ${MAKEFLAGS} CXX=${CXX} release
 
 debian-clean:
 	${MAKE} -C src/tetra/ ${MAKEFLAGS} CXX=${CXX} clean
@@ -54,6 +56,7 @@ debian-clean:
 	${MAKE} -C src/nanovg/ ${MAKEFLAGS} CXX=${CXX} clean
 	${MAKE} -C src/optflow/ ${MAKEFLAGS} CXX=${CXX} clean
 	${MAKE} -C src/beauty/ ${MAKEFLAGS} CXX=${CXX} clean
+	${MAKE} -C src/font/ ${MAKEFLAGS} CXX=${CXX} clean
 
 install: ${TARGET}
 	true

src/font/Makefile

@@ -0,0 +1,46 @@
+TARGET := font-demo
+
+SRCS    := font-demo.cpp
+
+#precompiled headers
+HEADERS := ../common/subsystems.hpp 
+OBJS    := ${SRCS:.cpp=.o}
+DEPS    := ${SRCS:.cpp=.dep} 
+
+CXXFLAGS += -fpic `pkg-config --cflags egl opencv4 libva-drm glew`
+LDFLAGS +=  
+LIBS += -lm `pkg-config --libs egl opencv4 libva-drm glew` -lnanovg
+.PHONY: all release debug clean distclean 
+
+all: release
+release: ${TARGET}
+debug: ${TARGET}
+info: ${TARGET}
+profile: ${TARGET}
+unsafe: ${TARGET}
+asan: ${TARGET}
+
+${TARGET}: ${OBJS}
+	${CXX} ${LDFLAGS} -o $@ $^ ${LIBS}
+
+${OBJS}: %.o: %.cpp %.dep ${GCH}
+	${CXX} ${CXXFLAGS} -o $@ -c $<
+
+${DEPS}: %.dep: %.cpp Makefile 
+	${CXX} ${CXXFLAGS} -MM $< > $@ 
+
+${GCH}: %.gch: ${HEADERS} 
+	${CXX} ${CXXFLAGS} -o $@ -c ${@:.gch=.hpp}
+
+install:
+	mkdir -p ${DESTDIR}/${PREFIX}
+	cp ${TARGET} ${DESTDIR}/${PREFIX}
+
+uninstall:
+	rm ${DESTDIR}/${PREFIX}/${TARGET}
+
+clean:
+	rm -f *~ ${DEPS} ${OBJS} ${CUO} ${GCH} ${TARGET} 
+
+distclean: clean
+

src/font/font-demo.cpp

@@ -0,0 +1,109 @@
+#define CL_TARGET_OPENCL_VERSION 120
+
+constexpr unsigned long WIDTH = 1920;
+constexpr unsigned long HEIGHT = 1080;
+constexpr bool OFFSCREEN = false;
+constexpr const char *OUTPUT_FILENAME = "font-demo.mkv";
+constexpr const int VA_HW_DEVICE_INDEX = 0;
+constexpr double FPS = 60;
+
+#include "../common/subsystems.hpp"
+
+#include <string>
+#include <algorithm>
+#include <vector>
+#include <sstream>
+
+using std::cerr;
+using std::endl;
+using std::string;
+using std::vector;
+using std::stringstream;
+
+int main(int argc, char **argv) {
+    using namespace kb;
+
+    //Initialize VP9 HW encoding using VAAPI
+    cv::VideoWriter writer(OUTPUT_FILENAME, cv::CAP_FFMPEG, cv::VideoWriter::fourcc('V', 'P', '9', '0'), FPS, cv::Size(WIDTH, HEIGHT), {
+            cv::VIDEOWRITER_PROP_HW_ACCELERATION, cv::VIDEO_ACCELERATION_VAAPI,
+            cv::VIDEOWRITER_PROP_HW_ACCELERATION_USE_OPENCL, 1
+    });
+
+    //Copy OpenCL Context for VAAPI. Must be called right after VideoWriter/VideoCapture initialization.
+    va::init();
+
+
+    if (!OFFSCREEN)
+        x11::init();
+    egl::init();
+    gl::init();
+    nvg::init();
+
+    cerr << "EGL Version: " << egl::get_info() << endl;
+    cerr << "OpenGL Version: " << gl::get_info() << endl;
+    cerr << "OpenCL Platforms: " << endl << cl::get_info() << endl;
+
+    cv::UMat frameBuffer;
+    cv::UMat videoFrame;
+
+    //Bind the OpenCL context for VAAPI
+    string text = cv::getBuildInformation();
+    size_t numLines = std::count(text.begin(), text.end(), '\n');
+    vector<cv::Point2f> src = {{0,0},{WIDTH,0},{WIDTH,HEIGHT},{0,HEIGHT}};
+    vector<cv::Point2f> dst = {{WIDTH/3.5,0},{WIDTH/1.4,0},{WIDTH,HEIGHT},{0,HEIGHT}};
+    cv::Mat M = cv::getPerspectiveTransform(src, dst);
+
+    float cnt = 0;
+    while (true) {
+        //Render using nanovg
+        gl::bind();
+        nvg::begin();
+        nvg::clear();
+        {
+            using kb::nvg::vg;
+
+            float lineh;
+            float y = 0;
+
+            nvgFontSize(vg, 45.0f);
+            nvgFontFace(vg, "serif");
+            nvgFillColor(vg, nvgHSLA(0.15, 1, 0.5, 255));
+            nvgTextAlign(vg, NVG_ALIGN_CENTER | NVG_ALIGN_TOP);
+            nvgTextMetrics(vg, NULL, NULL, &lineh);
+            nvgTranslate(vg, 0, cnt - ((numLines * lineh)));
+
+            std::istringstream iss(text);
+
+            for (std::string line; std::getline(iss, line); )
+            {
+                nvgText(vg, WIDTH/2.0, y, line.c_str(), line.c_str() + line.size());
+                y += lineh;
+            }
+        }
+        nvg::end();
+
+        //Aquire frame buffer from OpenGL
+        gl::acquire_from_gl(frameBuffer);
+        //Color-conversion from BGRA to RGB. OpenCV/OpenCL.
+        cv::warpPerspective(frameBuffer, frameBuffer, M, videoFrame.size(), cv::INTER_LINEAR, cv::BORDER_CONSTANT, cv::Scalar());
+        cv::cvtColor(frameBuffer, videoFrame, cv::COLOR_BGRA2RGB);
+        //Transfer buffer ownership back to OpenGL
+        gl::release_to_gl(frameBuffer);
+
+        //if x11 is enabled it displays the framebuffer in the native window. returns false if the window was closed.
+        if(!gl::display())
+            break;
+
+        //Activate the OpenCL context for VAAPI
+        va::bind();
+        //Encode the frame using VAAPI on the GPU.
+        writer << videoFrame;
+
+        print_fps();
+        ++cnt;
+        if(cnt > 1000000)
+            cnt = 1;
+    }
+
+    return 0;
+}