diff --git a/engines/myst3/gfx_tinygl_texture.cpp b/engines/myst3/gfx_tinygl_texture.cpp
index a753db5115a..36d52eb08d9 100644
--- a/engines/myst3/gfx_tinygl_texture.cpp
+++ b/engines/myst3/gfx_tinygl_texture.cpp
@@ -54,7 +54,7 @@ TinyGLTexture::TinyGLTexture(const Graphics::Surface *surface, bool nonPoTSuppor
 
 	if (format.bytesPerPixel == 4) {
 		internalFormat = TGL_RGBA;
-		sourceFormat = TGL_UNSIGNED_BYTE;
+		sourceFormat = TGL_UNSIGNED_INT_8_8_8_8_REV;
 	} else if (format.bytesPerPixel == 2) {
 		internalFormat = TGL_RGB;
 		sourceFormat = TGL_UNSIGNED_BYTE; // UNSIGNED_SHORT_5_6_5 not provided
diff --git a/graphics/tinygl/gl.h b/graphics/tinygl/gl.h
index 5205d672940..24b0f5ff978 100644
--- a/graphics/tinygl/gl.h
+++ b/graphics/tinygl/gl.h
@@ -585,6 +585,10 @@ enum {
 	TGL_RGB10_A2                    = 0x8059,
 	TGL_RGBA12                      = 0x805A,
 	TGL_RGBA16                      = 0x805B,
+	TGL_UNSIGNED_SHORT_5_6_5        = 0x8363,
+	TGL_UNSIGNED_SHORT_5_6_5_REV    = 0x8364,
+	TGL_UNSIGNED_INT_8_8_8_8        = 0x8035,
+	TGL_UNSIGNED_INT_8_8_8_8_REV    = 0x8367,
 
 	// Utility
 	TGL_VENDOR                      = 0x1F00,
diff --git a/graphics/tinygl/texture.cpp b/graphics/tinygl/texture.cpp
index cbda0085217..1c583cd959f 100644
--- a/graphics/tinygl/texture.cpp
+++ b/graphics/tinygl/texture.cpp
@@ -28,6 +28,8 @@
 
 // Texture Manager
 
+#include "common/endian.h"
+
 #include "graphics/tinygl/zgl.h"
 
 namespace TinyGL {
@@ -177,7 +179,12 @@ void glopTexImage2D(GLContext *c, GLParam *p) {
 			pixels = temp.getRawBuffer();
 			do_free_after_rgb2rgba = true;
 		}
-	} else if ((format != TGL_RGBA && format != TGL_RGB && format != TGL_BGR) || type != TGL_UNSIGNED_BYTE) {
+	} else if ((format != TGL_RGBA &&
+		    format != TGL_RGB &&
+		    format != TGL_BGR &&
+		    format != TGL_BGRA) ||
+		    (type != TGL_UNSIGNED_BYTE &&
+		     type != TGL_UNSIGNED_INT_8_8_8_8_REV)) {
 		error("tglTexImage2D: combination of parameters not handled");
 	}
 
@@ -191,6 +198,17 @@ void glopTexImage2D(GLContext *c, GLParam *p) {
 		} else {
 			memcpy(pixels1, pixels, c->_textureSize * c->_textureSize * bytes);
 		}
+#if defined(SCUMM_BIG_ENDIAN)
+		if (type == TGL_UNSIGNED_INT_8_8_8_8_REV) {
+			for (int y = 0; y < height; y++) {
+				for (int x = 0; x < width; x++) {
+					uint32 offset = (y * width + x) * 4;
+					byte *data = pixels1 + offset;
+					WRITE_BE_UINT32(data, READ_LE_UINT32(data));
+				}
+			}
+		}
+#endif
 	}
 
 	c->current_texture->versionNumber++;