sokol_gfx.h: improve validation messages (fixes #918)

sokol_gfx.h

@@ -3420,28 +3420,28 @@ typedef struct sg_frame_stats {
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_IB_EXISTS, "sg_apply_bindings: index buffer no longer alive") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_IB_TYPE, "sg_apply_bindings: buffer in index buffer slot is not a SG_BUFFERTYPE_INDEXBUFFER") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_IB_OVERFLOW, "sg_apply_bindings: buffer in index buffer slot is overflown") \
-    _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_EXPECTED_IMAGE_BINDING, "sg_apply_bindings: missing image binding on vertex stage") \
+    _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_EXPECTED_IMAGE_BINDING, "sg_apply_bindings: image binding on vertex stage is missing or the image handle is invalid") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_IMG_EXISTS, "sg_apply_bindings: image bound to vertex stage no longer alive") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_IMAGE_TYPE_MISMATCH, "sg_apply_bindings: type of image bound to vertex stage doesn't match shader desc") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_IMAGE_MSAA, "sg_apply_bindings: cannot bind image with sample_count>1 to vertex stage") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_EXPECTED_FILTERABLE_IMAGE, "sg_apply_bindings: filterable image expected on vertex stage") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_EXPECTED_DEPTH_IMAGE, "sg_apply_bindings: depth image expected on vertex stage") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_UNEXPECTED_IMAGE_BINDING, "sg_apply_bindings: unexpected image binding on vertex stage") \
-    _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_EXPECTED_SAMPLER_BINDING, "sg_apply_bindings: missing sampler binding on vertex stage") \
+    _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_EXPECTED_SAMPLER_BINDING, "sg_apply_bindings: sampler binding on vertex stage is missing or the sampler handle is invalid") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_UNEXPECTED_SAMPLER_COMPARE_NEVER, "sg_apply_bindings: shader expects SG_SAMPLERTYPE_COMPARISON on vertex stage but sampler has SG_COMPAREFUNC_NEVER") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_EXPECTED_SAMPLER_COMPARE_NEVER, "sg_apply_bindings: shader expects SG_SAMPLERTYPE_FILTERING or SG_SAMPLERTYPE_NONFILTERING on vertex stage but sampler doesn't have SG_COMPAREFUNC_NEVER") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_EXPECTED_NONFILTERING_SAMPLER, "sg_apply_bindings: shader expected SG_SAMPLERTYPE_NONFILTERING on vertex stage, but sampler has SG_FILTER_LINEAR filters") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_UNEXPECTED_SAMPLER_BINDING, "sg_apply_bindings: unexpected sampler binding on vertex stage") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_SMP_EXISTS, "sg_apply_bindings: sampler bound to vertex stage no longer alive") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_VS_IMG_SMP_MIPMAPS, "sg_apply_bindings: image bound to vertex stage has mipmap_count == 1, but associated sampler mipmap filer is not SG_MIPMAPFILTER_NONE") \
-    _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_EXPECTED_IMAGE_BINDING, "sg_apply_bindings: missing image binding on fragment stage") \
+    _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_EXPECTED_IMAGE_BINDING, "sg_apply_bindings: image binding on fragment stage is missing or the image handle is invalid") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_IMG_EXISTS, "sg_apply_bindings: image bound to fragment stage no longer alive") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_IMAGE_TYPE_MISMATCH, "sg_apply_bindings: type of image bound to fragment stage doesn't match shader desc") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_IMAGE_MSAA, "sg_apply_bindings: cannot bind image with sample_count>1 to fragment stage") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_EXPECTED_FILTERABLE_IMAGE, "sg_apply_bindings: filterable image expected on fragment stage") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_EXPECTED_DEPTH_IMAGE, "sg_apply_bindings: depth image expected on fragment stage") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_UNEXPECTED_IMAGE_BINDING, "sg_apply_bindings: unexpected image binding on fragment stage") \
-    _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_EXPECTED_SAMPLER_BINDING, "sg_apply_bindings: missing sampler binding on fragment stage") \
+    _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_EXPECTED_SAMPLER_BINDING, "sg_apply_bindings: sampler binding on fragment stage is missing or the sampler handle is invalid") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_UNEXPECTED_SAMPLER_COMPARE_NEVER, "sg_apply_bindings: shader expects SG_SAMPLERTYPE_COMPARISON on fragment stage but sampler has SG_COMPAREFUNC_NEVER") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_EXPECTED_SAMPLER_COMPARE_NEVER, "sg_apply_bindings: shader expects SG_SAMPLERTYPE_FILTERING on fragment stage but sampler doesn't have SG_COMPAREFUNC_NEVER") \
     _SG_LOGITEM_XMACRO(VALIDATE_ABND_FS_EXPECTED_NONFILTERING_SAMPLER, "sg_apply_bindings: shader expected SG_SAMPLERTYPE_NONFILTERING on fragment stage, but sampler has SG_FILTER_LINEAR filters") \