Ctlrender help (#38)

* updates help message with no input arguments

- updates ctlrender to produce verbose usage message when no input arguments are supplied
- minor formatting change to usage message

* updates help messages

- updates formatting of all messages for better command line readability
- provides hints on how to solve missing CTL parameter issues
- cravenly modifies commit messages to be slightly more professional

* updates help messages

- adds usage for -help and -force options
- updates language of overwrite warning

ctlrender/main.cc

@@ -468,11 +468,8 @@ int main(int argc, const char **argv)
 
 		if (input_image_files.size() < 2)
 		{
-			fprintf(stderr,
-					"one or more source filenames and a destination "
-					"file or directory must be\nprovided. if more than one "
-					"source filenames is provided then the last argument\nmust "
-					"be a directory. see -help for more details.\n");
+			usage(NULL);
+
 			exit(1);
 		}
 
@@ -509,9 +506,9 @@ int main(int argc, const char **argv)
 					if (!force_overwrite_output_file)
 					{
 						fprintf(stderr,
-								"The destination file %s already exists.\n"
-								"Cravenly refusing to overwrite unless you supply "
-								"the -force option.\n", outputFile);
+								"The destination file %s already exists. Refusing to overwrite the existing file.\n"
+								"To overwrite the existing file use the -force option.\n"
+								, outputFile);
 						exit(1);
 					}
 					else
@@ -588,8 +585,8 @@ int main(int argc, const char **argv)
 								"You have specified a destination file "
 								"type with the -format option, but the\noutput "
 								"file extension does not match the format "
-								"specified by the -format option.\nCravenly "
-								"refusing to do this unless you specify the "
+								"specified by the -format option.\nThis behavior "
+								"can be overridden by specifing the "
 								"-force option (which\nwill make the -format "
 								"option take priority).\n");
 						exit(1);
@@ -671,7 +668,7 @@ int main(int argc, const char **argv)
 			}
 			if (access(outputFile, F_OK) >= 0)
 			{
-				fprintf(stderr, "Cravenly refusing to overwrite the file '%s'.\n", outputFile);
+				fprintf(stderr, "Can not overwrite the file '%s'.\n", outputFile);
 				exit(1);
 			}
 			actual_format.squish = noalpha;
@@ -683,7 +680,7 @@ int main(int argc, const char **argv)
 
 	} catch (std::exception &e)
 	{
-		fprintf(stderr, "exception thrown (oops...): %s\n", e.what());
+		fprintf(stderr, "\nexception thrown (oops...): %s\n", e.what());
 		return 1;
 	}
 }

ctlrender/transform.cc

@@ -184,7 +184,7 @@ void set_ctl_function_argument_from_ctl_results(Ctl::FunctionArgPtr *arg, const
 		}
 		else
 		{
-			THROW(Iex::ArgExc, "CTL parameter '" << dst->name() << "' not specified on the command line and does not have a default value.");
+			THROW(Iex::ArgExc, "A value for the CTL input variable '" << dst->name() << "' does not exist, was not specified on the command line,\nand does not have a default value. A value can be provided at runtime using command line parameters. See '-help param'\n");
 			throw(std::exception());
 		}
 		return;

ctlrender/usage.cc

@@ -58,7 +58,7 @@
 
 void usage(const char *section) {
 	if(section==NULL) {
-		fprintf(stdout, ""
+		fprintf(stdout, "\n"
 "ctlrender - transforms an image using one or more CTL scripts, potentially\n"
 "            converting the file format in the process\n"
 "\nusage:\n"
@@ -110,9 +110,18 @@ void usage(const char *section) {
 "\n"
 "    -verbose              Increases the level of output verbosity.\n"
 "    -quiet                Decreases the level of output verbosity.\n"
-"");
+"\n"
+"    -force                Overrides the default program behavior in some\n"
+"                          instances such as overwriting existing files and\n"
+"                          requiring format specified and file extensions\n"
+"                          match.\n"
+"\n"
+"    -help                 Prints this message. Additional help details are\n"
+"                          available for some options by specifying an option\n"
+"                          after '-help' (e.g. '-help format').\n"
+"\n");
 	} else if(!strncmp(section, "format", 1)) {
-		fprintf(stdout, ""
+		fprintf(stdout, "\n"
 "format conversion:\n"
 "\n"
 "    ctlrender provides file format conversion either implicitly by the\n"
@@ -156,10 +165,10 @@ void usage(const char *section) {
 "\n"
 "    Note that no automatic depth scaling is performed, please see\n"
 "    '-help scale' for more details on how scaling is performed.\n"
-"");
+"\n");
     } else if(!strncmp(section, "compression", 2)) {
 #if defined(HAVE_OPENEXR)
-        fprintf(stdout, ""
+        fprintf(stdout, "\n"
 "exr compression:\n"
 "\n"
 "    ctlrender provides the option of a compression scheme when saving an \n"
@@ -185,9 +194,9 @@ void usage(const char *section) {
 "\n"
 "        B44A    (lossy) Like B44 but smaller for images containing large\n"
 "                uniform areas.\n"
-"");
+"\n");
 #else
-        fprintf(stdout, ""
+        fprintf(stdout, "\n"
 "exr compression:\n"
 "\n"
 "    ctlrender provides the option of a compression scheme when saving an \n"
@@ -198,21 +207,21 @@ void usage(const char *section) {
 "\n"
 "    OpenEXR support must be enabled for the '-compression' option to be\n"
 "    meaningful. Please see build documentation for details.\n"
-"");
+"\n");
 #endif
 	} else if(!strncmp(section, "ctl", 1)) {
-		fprintf(stdout, ""
+		fprintf(stdout, "\n"
 "ctl file interpretation:\n"
 "    ctlrender treats all ctl files as if they take their input as 'R', 'G',\n"
 "    'B', and 'A' (optional) channels, and produce output as 'R', 'G', and\n"
 "    'B', and 'A' (if required) channels. In the event of a single channel\n"
 "    input file only the 'G' channel will be used.\n"
-"");
+"\n");
 //"    The *LAST* function in the file is the function that will be called to\n"
 //"    provide the transform. This is to maintain compatability with scripts\n"
 //"    developed for Autodesk's TOXIC product.\n"
 	} else if(!strncmp(section, "scale", 1)) {
-		fprintf(stderr, ""
+		fprintf(stderr, "\n"
 "input and output value scaling:\n"
 "\n"
 "    To deal with differences in input and output file bit depth, the ability\n"
@@ -258,9 +267,9 @@ void usage(const char *section) {
 "\n"
 "    In all cases the CTL output values (after output_scaling) are clipped\n"
 "    to the maximum values supported by the output file format.\n"
-"");
+"\n");
 	} else if(!strncmp(section, "param", 1)) {
-		fprintf(stdout, ""
+		fprintf(stdout, "\n"
 "ctl parameters:\n"
 "\n"
 "    In CTL scripts it is possible to define parameters that are not set\n"
@@ -275,7 +284,7 @@ void usage(const char *section) {
 "        -global_param1 <name> <float1>\n"
 "        -global_param2 <name> <float1> <float2>\n"
 "        -global_param3 <name> <float1> <float2> <float3>\n"
-"");
+"\n");
 	} else {
 		fprintf(stdout, ""
 "The '%s' section of the help does not exist. Try running ctlrender with\n"