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-rw-r--r--src/gallium/auxiliary/util/u_format_r11g11b10f.h42
1 files changed, 31 insertions, 11 deletions
diff --git a/src/gallium/auxiliary/util/u_format_r11g11b10f.h b/src/gallium/auxiliary/util/u_format_r11g11b10f.h
index 000a5c25bfc..6bb4302965a 100644
--- a/src/gallium/auxiliary/util/u_format_r11g11b10f.h
+++ b/src/gallium/auxiliary/util/u_format_r11g11b10f.h
@@ -60,13 +60,23 @@ static INLINE unsigned f32_to_uf11(float val)
int exponent = ((f32.ui >> 23) & 0xff) - 127;
int mantissa = f32.ui & 0x007fffff;
- if (sign) return 0;
-
if (exponent == 128) { /* Infinity or NaN */
+ /* From the GL_EXT_packed_float spec:
+ *
+ * "Additionally: negative infinity is converted to zero; positive
+ * infinity is converted to positive infinity; and both positive and
+ * negative NaN are converted to positive NaN."
+ */
uf11 = UF11_MAX_EXPONENT;
- if (mantissa) uf11 |= (mantissa & UF11_MANTISSA_BITS);
- }
- else if (val > 65024.0f) {
+ if (mantissa) {
+ uf11 |= 1; /* NaN */
+ } else {
+ if (sign)
+ uf11 = 0; /* 0.0 */
+ }
+ } else if (sign) {
+ return 0;
+ } else if (val > 65024.0f) {
/* From the GL_EXT_packed_float spec:
*
* "Likewise, finite positive values greater than 65024 (the maximum
@@ -136,13 +146,23 @@ static INLINE unsigned f32_to_uf10(float val)
int exponent = ((f32.ui >> 23) & 0xff) - 127;
int mantissa = f32.ui & 0x007fffff;
- if (sign) return 0;
-
- if (exponent == 128) { /* Infinity or NaN */
+ if (exponent == 128) {
+ /* From the GL_EXT_packed_float spec:
+ *
+ * "Additionally: negative infinity is converted to zero; positive
+ * infinity is converted to positive infinity; and both positive and
+ * negative NaN are converted to positive NaN."
+ */
uf10 = UF10_MAX_EXPONENT;
- if (mantissa) uf10 |= (mantissa & UF10_MANTISSA_BITS);
- }
- else if (val > 64512.0f) { /* Overflow - flush to Infinity */
+ if (mantissa) {
+ uf10 |= 1; /* NaN */
+ } else {
+ if (sign)
+ uf10 = 0; /* 0.0 */
+ }
+ } else if (sign) {
+ return 0;
+ } else if (val > 64512.0f) { /* Overflow - flush to Infinity */
/* From the GL_EXT_packed_float spec:
*
* "Likewise, finite positive values greater than 64512 (the maximum