Initial CairoHelper

Added a new class for common cairo functions.

* #25
* NatronGitHub/Natron#970

Author: rodlie

Bundle/Makefile

@@ -51,6 +51,7 @@ PLUGINOBJECTS += \
     Text.o \
     Morphology.o \
     MagickPlugin.o \
+    CairoHelper.o \
     ofxsOGLTextRenderer.o \
     ofxsOGLFontData.o \
     ofxsRectangleInteract.o \
@@ -147,6 +148,7 @@ VPATH += \
     $(SRCDIR)/Magick/Roll \
     $(SRCDIR)/Magick/Wave \
     $(SRCDIR)/Magick/Morphology \
+    $(SRCDIR)/Helpers \
     $(SRCDIR)/lodepng
 
 ifeq ($(AUDIO), ON)
@@ -156,6 +158,7 @@ endif
 CXXFLAGS += \
     -I$(SRCDIR)/Extra \
     -I$(SRCDIR)/Magick \
+    -I$(SRCDIR)/Helpers \
     -I$(SRCDIR)/lodepng
 
 include $(SRCDIR)/Makefile.master
@@ -187,7 +190,7 @@ CXXFLAGS += $(SOX_CXXFLAGS)
 LINKFLAGS += $(SOX_LINKFLAGS)
 endif
 
-CXXFLAGS += -I. -I$(SRCDIR)/Magick -I$(SRCDIR)/Text -I$(SRCDIR)/lodepng
+CXXFLAGS += -I. -I$(SRCDIR)/Magick -I$(SRCDIR)/Text -I$(SRCDIR)/Helpers -I$(SRCDIR)/lodepng
 
 ifneq ($(LICENSE),COMMERCIAL)
 CXXFLAGS += $(POPPLER_CXXFLAGS)

CMakeLists.txt

@@ -115,6 +115,7 @@ INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR}/Extra)
 INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR}/Audio)
 INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR}/Bundle)
 INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR}/Text)
+INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR}/Helpers)
 INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR}/lodepng)
 #INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR}/OCL)
 
@@ -161,6 +162,7 @@ FILE(GLOB SOURCES
     "Extra/OpenRaster.cpp"
     "Extra/ReadCDR.cpp"
     "Extra/ReadKrita.cpp"
+    "Helpers/CairoHelper.cpp"
     "Magick/Arc.cpp"
     "Magick/Charcoal.cpp"
     "Magick/Edges.cpp"

Extra/Makefile

@@ -12,6 +12,7 @@ PLUGINOBJECTS += ReadPDF.o
 endif
 
 PLUGINOBJECTS += \
+    CairoHelper.o \
     ofxsTransform3x3.o \
     ofxsTransformInteract.o \
     ofxsShutter.o \
@@ -40,7 +41,7 @@ SRCDIR = ..
 include $(SRCDIR)/Makefile.master
 include $(SRCDIR)/Makefile.io
 
-VPATH += $(SRCDIR)/lodepng
+VPATH += $(SRCDIR)/lodepng $(SRCDIR)/Helpers
 
 CXXFLAGS  += \
     $(FCONFIG_CXXFLAGS) \
@@ -49,6 +50,7 @@ CXXFLAGS  += \
     $(XML_CXXFLAGS) \
     $(ZIP_CXXFLAGS) \
     $(GLIB_CXXFLAGS) \
+    -I$(SRCDIR)/Helpers \
     -I$(SRCDIR)/lodepng
 
 LINKFLAGS += \

Helpers/CairoHelper.cpp

@@ -0,0 +1,41 @@
+/*
+####################################################################
+#
+# Copyright (C) 2024 Ole-André Rodlie <https://github.com/rodlie>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+####################################################################
+*/
+
+#include "CairoHelper.h"
+
+#include <cmath>
+
+void CairoHelper::applyRotate(cairo_t *cr,
+                              double rotate,
+                              XY origin)
+{
+    if (!cr || rotate == 0.) { return; }
+
+    cairo_translate(cr, origin.x, origin.y);
+    cairo_rotate(cr, -rotate * (M_PI / 180.0));
+    cairo_translate(cr, -origin.x, -origin.y);
+}
+
+void CairoHelper::applyFlip(cairo_t *cr,
+                            int height)
+{
+    if (!cr || height < 1) { return; }
+
+    cairo_scale(cr, 1.0f, -1.0f);
+    cairo_translate(cr, 0.0f, -height);
+}

Helpers/CairoHelper.h

@@ -0,0 +1,41 @@
+/*
+####################################################################
+#
+# Copyright (C) 2024 Ole-André Rodlie <https://github.com/rodlie>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+####################################################################
+*/
+
+#ifndef CAIROHELPER_H
+#define CAIROHELPER_H
+
+#include <cairo.h>
+
+class CairoHelper
+{
+public:
+    struct XY
+    {
+        double x;
+        double y;
+    };
+    /** @brief apply rotate */
+    static void applyRotate(cairo_t *cr,
+                            double rotate,
+                            XY origin);
+    /** @brief apply flip */
+    static void applyFlip(cairo_t *cr,
+                          int height);
+};
+
+#endif // CAIROHELPER_H