Allow a threshold percentage for block modes

solidpixel · solidpixel · commit 82df2fd77379 · 2022-02-22T10:18:14.000Z
diff --git a/Source/astcenc_block_sizes.cpp b/Source/astcenc_block_sizes.cpp
@@ -854,6 +854,8 @@ static void construct_block_size_descriptor_2d(
 	unsigned int always_block_mode_count = 0;
 	unsigned int always_decimation_mode_count = 0;
 
+	float always_threshold = 0.0f;
+
 	// Iterate twice; first time keep the "always" blocks, second time keep the "non-always" blocks.
 	// This ensures that the always block modes and decimation modes are at the start of the list.
 	for (unsigned int j = 0; j < 2; j ++)
@@ -869,12 +871,12 @@ static void construct_block_size_descriptor_2d(
 			float percentile = percentiles[i];
 			bool selected = (percentile <= mode_cutoff) || !can_omit_modes;
 
-			if (j == 0 && percentile != 0.0f)
+			if (j == 0 && percentile > always_threshold)
 			{
 				continue;
 			}
 
-			if (j == 1 && percentile == 0.0f)
+			if (j == 1 && percentile <= always_threshold)
 			{
 				continue;
 			}
@@ -911,7 +913,7 @@ static void construct_block_size_descriptor_2d(
 				decimation_mode_index[y_weights * 16 + x_weights] = decimation_mode;
 
 	#if !defined(ASTCENC_DECOMPRESS_ONLY)
-				if (percentile == 0.0f)
+				if (percentile <= always_threshold)
 				{
 					always_decimation_mode_count++;
 				}
@@ -920,7 +922,7 @@ static void construct_block_size_descriptor_2d(
 
 	#if !defined(ASTCENC_DECOMPRESS_ONLY)
 			// Flatten the block mode heuristic into some precomputed flags
-			if (percentile == 0.0f)
+			if (percentile <= always_threshold)
 			{
 				always_block_mode_count++;
 				bsd.block_modes[packed_idx].percentile_hit = true;

Original file line number	Diff line number	Diff line change
`@@ -854,6 +854,8 @@ static void construct_block_size_descriptor_2d(`
`854`	`854`	`unsigned int always_block_mode_count = 0;`
`855`	`855`	`unsigned int always_decimation_mode_count = 0;`
`856`	`856`
	`857`	`+ float always_threshold = 0.0f;`
	`858`	`+`
`857`	`859`	`// Iterate twice; first time keep the "always" blocks, second time keep the "non-always" blocks.`
`858`	`860`	`// This ensures that the always block modes and decimation modes are at the start of the list.`
`859`	`861`	`for (unsigned int j = 0; j < 2; j ++)`
`@@ -869,12 +871,12 @@ static void construct_block_size_descriptor_2d(`
`869`	`871`	`float percentile = percentiles[i];`
`870`	`872`	`bool selected = (percentile <= mode_cutoff) \|\| !can_omit_modes;`
`871`	`873`
`872`		`- if (j == 0 && percentile != 0.0f)`
	`874`	`+ if (j == 0 && percentile > always_threshold)`
`873`	`875`	`{`
`874`	`876`	`continue;`
`875`	`877`	`}`
`876`	`878`
`877`		`- if (j == 1 && percentile == 0.0f)`
	`879`	`+ if (j == 1 && percentile <= always_threshold)`
`878`	`880`	`{`
`879`	`881`	`continue;`
`880`	`882`	`}`
`@@ -911,7 +913,7 @@ static void construct_block_size_descriptor_2d(`
`911`	`913`	`decimation_mode_index[y_weights * 16 + x_weights] = decimation_mode;`
`912`	`914`
`913`	`915`	`#if !defined(ASTCENC_DECOMPRESS_ONLY)`
`914`		`- if (percentile == 0.0f)`
	`916`	`+ if (percentile <= always_threshold)`
`915`	`917`	`{`
`916`	`918`	`always_decimation_mode_count++;`
`917`	`919`	`}`
`@@ -920,7 +922,7 @@ static void construct_block_size_descriptor_2d(`
`920`	`922`
`921`	`923`	`#if !defined(ASTCENC_DECOMPRESS_ONLY)`
`922`	`924`	`// Flatten the block mode heuristic into some precomputed flags`
`923`		`- if (percentile == 0.0f)`
	`925`	`+ if (percentile <= always_threshold)`
`924`	`926`	`{`
`925`	`927`	`always_block_mode_count++;`
`926`	`928`	`bsd.block_modes[packed_idx].percentile_hit = true;`