diff --git a/source/glbackend/gl_hwtexture.cpp b/source/glbackend/gl_hwtexture.cpp
index 8c43bde40..1ce4d147f 100644
--- a/source/glbackend/gl_hwtexture.cpp
+++ b/source/glbackend/gl_hwtexture.cpp
@@ -64,19 +64,35 @@ unsigned int FHardwareTexture::CreateTexture(int w, int h, bool eightbit, bool m
 //
 //===========================================================================
 
-unsigned int FHardwareTexture::LoadTexture(unsigned char * buffer)
+unsigned int FHardwareTexture::LoadTexture(const unsigned char * buffer)
+{
+	return LoadTexturePart(buffer, 0, 0, mWidth, mHeight);
+}
+
+unsigned int FHardwareTexture::LoadTexture(FBitmap& bmp)
+{
+	return LoadTexture(bmp.GetPixels());
+}
+
+//===========================================================================
+// 
+//	Loads the texture image into the hardware
+//
+//===========================================================================
+
+unsigned int FHardwareTexture::LoadTexturePart(const unsigned char* buffer, int x, int y, int w, int h)
 {
 	if (glTexID == 0) return 0;
 
-	int dstformat = glTextureBytes == 1? GL_R8 : GL_RGBA8;// TexFormat[gl_texture_format];
+	int dstformat = glTextureBytes == 1 ? GL_R8 : GL_RGBA8;// TexFormat[gl_texture_format];
 	int srcformat = glTextureBytes == 1 ? GL_RED : GL_BGRA;// TexFormat[gl_texture_format];
 
 	glActiveTexture(GL_TEXTURE15);
 	glBindTexture(GL_TEXTURE_2D, glTexID);
 
 	if (glTextureBytes < 4) glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
-	
-	glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, mWidth, mHeight, srcformat, GL_UNSIGNED_BYTE, buffer);
+
+	glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, w, h, srcformat, GL_UNSIGNED_BYTE, buffer);
 	if (mipmapped) glGenerateMipmap(GL_TEXTURE_2D);
 
 	glBindTexture(GL_TEXTURE_2D, 0);
@@ -85,11 +101,6 @@ unsigned int FHardwareTexture::LoadTexture(unsigned char * buffer)
 	return glTexID;
 }
 
-unsigned int FHardwareTexture::LoadTexture(FBitmap& bmp)
-{
-	return LoadTexture(bmp.GetPixels());
-}
-
 //===========================================================================
 // 
 //	Destroys the texture
diff --git a/source/glbackend/gl_hwtexture.h b/source/glbackend/gl_hwtexture.h
index 9493eb2cf..afb804794 100644
--- a/source/glbackend/gl_hwtexture.h
+++ b/source/glbackend/gl_hwtexture.h
@@ -27,7 +27,8 @@ public:
 	//bool BindOrCreate(FTexture *tex, int texunit, int clampmode, int translation, int flags);
 
 	unsigned int CreateTexture(int w, int h, bool eightbit, bool mipmapped);
-	unsigned int LoadTexture(unsigned char * buffer);
+	unsigned int LoadTexture(const unsigned char * buffer);
+	unsigned int LoadTexturePart(const unsigned char* buffer, int x, int y, int w, int h);
 	unsigned int LoadTexture(FBitmap &bmp);
 	unsigned int GetTextureHandle();
 	int GetSampler() { return mSampler; }
diff --git a/source/glbackend/gl_palmanager.cpp b/source/glbackend/gl_palmanager.cpp
index 997314e9b..0b80386b7 100644
--- a/source/glbackend/gl_palmanager.cpp
+++ b/source/glbackend/gl_palmanager.cpp
@@ -35,10 +35,7 @@
 
 #include <memory>
 #include "m_crc32.h"
-#include "glad/glad.h"
 #include "glbackend.h"
-#include "gl_samplers.h"
-#include "gl_shader.h"
 
 #include "baselayer.h"
 #include "resourcefile.h"
@@ -214,13 +211,28 @@ void PaletteManager::BindPalette(int index)
 
 void PaletteManager::SetPalswapData(int index, const uint8_t* data, int numshades_)
 {
-	// New palettes may only be added if declared transient or on startup. 
-	// Otherwise this would require a renderer reset to flush out the textures affected by the change.
-
 	if (index < 0 || index > 255) return;	// invalid index - ignore.
 	numshades = numshades_;
 	palswapmap[index] = FindPalswap(data);
 
+	if (palswapTexture == nullptr)
+	{
+		palswapTexture = inst->NewTexture();
+		palswapTexture->CreateTexture(PALSWAP_TEXTURE_SIZE, PALSWAP_TEXTURE_SIZE, true, false);
+		palswapTexture->SetSampler(Sampler2DNoFilter);
+	}
+	else inst->UnbindTexture(1);	// Unbind for updating.
+
+	int32_t column = index % (PALSWAP_TEXTURE_SIZE / 256);
+	int32_t row = index / (PALSWAP_TEXTURE_SIZE / 256);
+	int32_t rowOffset = (numshades + 1) * row;
+	if (rowOffset > PALSWAP_TEXTURE_SIZE)
+	{
+		OSD_Printf("Polymost: palswaps are too large for palswap tilesheet!\n");
+		return;
+	}
+	palswapTexture->LoadTexturePart(data, 256 * column, rowOffset, 256, numshades + 1);
+
 }
 
 //===========================================================================
@@ -231,7 +243,6 @@ void PaletteManager::SetPalswapData(int index, const uint8_t* data, int numshade
 
 void PaletteManager::UpdatePalswaps(int width, int height)
 {
-	if (palswapTexture) delete palswapTexture;
 	for (auto& pal : palettes)
 	{
 		pal.shadesdone = false;
@@ -245,72 +256,5 @@ void PaletteManager::UpdatePalswaps(int width, int height)
 								  (height - 1) * (1.f / PALSWAP_TEXTURE_SIZE) };
 
 	inst->SetPalswapSize(&polymost1PalswapInnerSize.x);
-
+	inst->BindTexture(1, palswapTexture);
 }
-
-
-void GLInstance::SetPalswap(int index)
-{
-	float v1 = index * renderState.PalswapSize[0];
-	float v2 = floorf(v1);
-	renderState.PalswapPos[0] = v1 - v2 + (0.5f / PALSWAP_TEXTURE_SIZE);
-	renderState.PalswapPos[1] = v2 * renderState.PalswapSize[1] + (0.5f / PALSWAP_TEXTURE_SIZE);
-}
-
-
-#if 0
-
-static void polymost_setPalswapSize(uint32_t width, uint32_t height)
-{
-	if (currentShaderProgramID != polymost1CurrentShaderProgramID)
-		return;
-
-}
-
-
-#endif
-
-// No point porting this, it's too much work for a short lived solution.
-#if 0
-char allocateTexture = !palswapTextureID;
-if (allocateTexture)
-{
-	G etTextureHandle(&palswapTextureID);
-}
-g lBindTexture(GL _TEXTURE_2D, palswapTextureID);
-if (allocateTexture)
-{
-	g lTexParameteri(GL _TEXTURE_2D, GL _TEXTURE_BASE_LEVEL, 0);
-	g lTexParameteri(GL _TEXTURE_2D, GL _TEXTURE_MAX_LEVEL, 0);
-	g lTexParameteri(GL _TEXTURE_2D, GL _TEXTURE_MAG_FILTER, GL _NEAREST);
-	g lTexParameteri(GL _TEXTURE_2D, GL _TEXTURE_MIN_FILTER, GL _NEAREST);
-	g lTexParameteri(GL _TEXTURE_2D, GL _TEXTURE_MAX_ANISOTROPY_EXT, 1);
-	g lTexParameteri(GL _TEXTURE_2D, GL _TEXTURE_WRAP_S, GL _CLAMP_TO_EDGE);
-	g lTexParameteri(GL _TEXTURE_2D, GL _TEXTURE_WRAP_T, GL _CLAMP_TO_EDGE);
-	g lTexImage2D(GL _TEXTURE_2D, 0, GL _RED, PALSWAP_TEXTURE_SIZE, PALSWAP_TEXTURE_SIZE, 0, GL _RED, GL _UNSIGNED_BYTE, NULL);
-}
-
-int32_t column = palookupnum % (PALSWAP_TEXTURE_SIZE / 256);
-int32_t row = palookupnum / (PALSWAP_TEXTURE_SIZE / 256);
-int32_t rowOffset = (numshades + 1) * row;
-if (rowOffset > PALSWAP_TEXTURE_SIZE)
-{
-	OSD_Printf("Polymost: palswaps are too large for palswap tilesheet!\n");
-	return;
-}
-g lTexSubImage2D(GL _TEXTURE_2D, 0, 256 * column, rowOffset, 256, numshades + 1, GL _RED, GL _UNSIGNED_BYTE, palookup[palookupnum]);
-
-polymost_setPalswapSize(256, numshades + 1);
-
-static void polymost_updatePalette()
-{
-	if (videoGetRenderMode() != REND_POLYMOST)
-	{
-		return;
-	}
-
-	polymost_setPalswap(globalpal);
-	polymost_setShade(globalshade);
-
-}
-#endif
diff --git a/source/glbackend/glbackend.cpp b/source/glbackend/glbackend.cpp
index ffa7cd12e..c0868b907 100644
--- a/source/glbackend/glbackend.cpp
+++ b/source/glbackend/glbackend.cpp
@@ -438,6 +438,16 @@ void GLInstance::SetPalette(int index)
 	palmanager.BindPalette(index);
 }
 
+
+void GLInstance::SetPalswap(int index)
+{
+	float v1 = index * renderState.PalswapSize[0];
+	float v2 = floorf(v1);
+	renderState.PalswapPos[0] = v1 - v2 + (0.5f / PALSWAP_TEXTURE_SIZE);
+	renderState.PalswapPos[1] = v2 * renderState.PalswapSize[1] + (0.5f / PALSWAP_TEXTURE_SIZE);
+}
+
+
 void PolymostRenderState::Apply(PolymostShader* shader)
 {
 	shader->Clamp.Set(Clamp);
diff --git a/source/glbackend/glbackend.h b/source/glbackend/glbackend.h
index c18f5ca19..4dd9287e9 100644
--- a/source/glbackend/glbackend.h
+++ b/source/glbackend/glbackend.h
@@ -22,6 +22,7 @@ struct PaletteData
 	PalEntry colors[256];
 	float shades[512];	// two values (addshade and mulshade for each palswap.)
 	bool shadesdone;
+	int whiteindex, blackindex;
 	FHardwareTexture* paltexture;
 };