In your Makefile, add the following:

include $(YAUL_INSTALL_ROOT)/share/build.tga.mk

For C, in your Makefile, add the following:

SH_CFLAGS+= $(TGA_CFLAGS)

For C++, in your Makefile, use SH_CXXFLAGS instead:

SH_CXXFLAGS+= $(TGA_CXXFLAGS)

For both C and C++:

SH_LDFLAGS+= $(TGA_LDFLAGS)