Improve stress test to detect errors in the output.

src/nvtt/tests/stress.cpp

@@ -24,9 +24,64 @@
 #include <nvtt/nvtt.h>
 
 #include <stdio.h> // printf
-#include <stdlib.h> // rand?
+#include <stdlib.h> // rand
 #include <time.h> // clock
+#include <string.h> // memcpy, memcmp
+#include <assert.h>
 
+#define FRAME_COUNT  1000
+
+#define WIDTH        1024
+#define HEIGHT       1024
+#define INPUT_SIZE   (WIDTH*HEIGHT)
+#define OUTPUT_SIZE  (WIDTH*HEIGHT/16*2)
+
+static int s_input[INPUT_SIZE];
+static int s_reference[OUTPUT_SIZE];
+static int s_output[OUTPUT_SIZE];
+static int s_frame = 0;
+
+struct MyOutputHandler : public nvtt::OutputHandler
+{
+	MyOutputHandler() : m_ptr(NULL) {}
+	
+	virtual void beginImage(int size, int width, int height, int depth, int face, int miplevel)
+	{
+		assert(size == OUTPUT_SIZE);
+		assert(width == WIDTH);
+		assert(height == HEIGHT);
+		assert(depth == 1);
+		assert(face == 0);
+		assert(miplevel == 0);
+
+		m_ptr = (unsigned char *)s_output;
+
+		if (s_frame == 1)
+		{
+			// Save first result as reference.
+			memcpy(s_reference, s_output, sizeof(int) * OUTPUT_SIZE);
+		}
+		else if (s_frame > 1)
+		{
+			// Compare against reference.
+			if (memcmp(s_output, s_reference, sizeof(int) * OUTPUT_SIZE) != 0)
+			{
+				printf("Compressed image different to original.\n");
+				exit(EXIT_FAILURE);
+			}
+		}
+	}
+	
+	virtual bool writeData(const void * data, int size)
+	{
+		memcpy(m_ptr, data, size);
+		m_ptr += size;
+		return true;
+	}
+
+	unsigned char * m_ptr;
+
+};
 
 
 int main(int argc, char *argv[])
@@ -34,29 +89,37 @@ int main(int argc, char *argv[])
 	nvtt::InputOptions inputOptions;
 	inputOptions.setTextureLayout(nvtt::TextureType_2D, 1024, 1024);
 
-	int * data = (int *)malloc(1024 * 1024 * 4);
 	for (int i = 0; i < 1024 * 1024; i++)
 	{
-		data[i] = rand();
+		s_input[i] = rand();
 	}
 
-	inputOptions.setMipmapData(data, 1024, 1024);
+	inputOptions.setMipmapData(s_input, 1024, 1024);
 	inputOptions.setMipmapGeneration(false);
 
 	nvtt::CompressionOptions compressionOptions;
+	
 	nvtt::OutputOptions outputOptions;
+	outputOptions.setOutputHeader(false);
+
+	MyOutputHandler outputHandler;
+	outputOptions.setOutputHandler(&outputHandler);
+
+
 	nvtt::Compressor compressor;
 
-	for (int i = 0; i < 1000; i++)
+	for (s_frame = 0; s_frame < FRAME_COUNT; s_frame++)
 	{
 		clock_t start = clock();
 
+		printf("compressing frame %d:\n", s_frame);
+
 		compressor.process(inputOptions, compressionOptions, outputOptions);
 
 		clock_t end = clock();
 		printf("time taken: %.3f seconds\n", float(end-start) / CLOCKS_PER_SEC);
 	}
 
-	return 0;
+	return EXIT_SUCCESS;
 }