From ef6ea26fd8a8705fbd3b4bfbb9049da46a9ed61a Mon Sep 17 00:00:00 2001
From: Paul Hontz <paul@thestartupfoundry.com>
Date: Tue, 6 Oct 2026 13:21:30 -0400
Subject: [PATCH] Renderer: a draw's changed texture units bound in one call
 (desktop GL)

---
 port/linux/src/d3d8_gl.c | 40 +++++++++++++++++++++++++++++++++++++++-
 port/linux/src/gl.h      |  2 ++
 2 files changed, 41 insertions(+), 1 deletion(-)

diff --git a/port/linux/src/d3d8_gl.c b/port/linux/src/d3d8_gl.c
index c85171ae..cc4f39fa 100644
--- a/port/linux/src/d3d8_gl.c
+++ b/port/linux/src/d3d8_gl.c
@@ -729,9 +729,16 @@ static void state_framebuffer(GLuint framebuffer)
 	}
 }
 
+/* gl_state.textures' slot of a target */
+static int texture_slot(GLenum target)
+{
+	return target == GL_TEXTURE_CUBE_MAP ? 1 : target == GL_TEXTURE_3D ? 2 : 0;
+}
+
+#ifdef HALO_ANDROID
 static void state_texture(int unit, GLenum target, GLuint texture)
 {
-	int slot = target == GL_TEXTURE_CUBE_MAP ? 1 : target == GL_TEXTURE_3D ? 2 : 0;
+	int slot = texture_slot(target);
 
 	if (gl_state.textures[unit][slot] == texture)
 		return;
@@ -743,6 +750,7 @@ static void state_texture(int unit, GLenum target, GLuint texture)
 	gl_state.textures[unit][slot] = texture;
 	glBindTexture(target, texture);
 }
+#endif
 
 static void state_sampler(int unit, GLuint sampler)
 {
@@ -2934,8 +2942,38 @@ static void bind_textures(struct nv2a_pixel_shader_key *key, float texture_scale
 				gl_target == GL_TEXTURE_3D ? _xgpu_sampler_3d : _xgpu_sampler_2d;
 		}
 	}
+#ifdef HALO_ANDROID
 	for (stage = 0; stage < D3DTSS_MAXSTAGES; stage++)
 		state_texture(stage, gl_targets[stage], gl_textures[stage]);
+#else
+	{
+		/* the units whose texture changes, bound in one call (GL 4.4's
+		multi-bind) rather than selecting and binding each unit; binding no
+		texture unbinds all of the unit's targets */
+		int first = -1, last = -1;
+
+		for (stage = 0; stage < D3DTSS_MAXSTAGES; stage++)
+		{
+			if (gl_state.textures[stage][texture_slot(gl_targets[stage])] != gl_textures[stage])
+			{
+				if (first < 0)
+					first = stage;
+				last = stage;
+			}
+		}
+		if (first >= 0)
+		{
+			glBindTextures((GLuint)first, (GLsizei)(last - first + 1), &gl_textures[first]);
+			for (stage = first; stage <= last; stage++)
+			{
+				if (gl_textures[stage])
+					gl_state.textures[stage][texture_slot(gl_targets[stage])] = gl_textures[stage];
+				else
+					memset(gl_state.textures[stage], 0, sizeof(gl_state.textures[stage]));
+			}
+		}
+	}
+#endif
 }
 
 static GLenum stencil_operation(DWORD operation)
diff --git a/port/linux/src/gl.h b/port/linux/src/gl.h
index 219a5730..16e4b74c 100644
--- a/port/linux/src/gl.h
+++ b/port/linux/src/gl.h
@@ -217,6 +217,7 @@ this list to generate the guest's entry points */
 	X(glVertexAttribIFormat) \
 	X(glVertexAttribBinding) \
 	X(glBindVertexBuffer) \
+	X(glBindTextures) \
 	X(glGetQueryBufferObjectuiv) \
 	X(glVertexAttrib4fv) \
 	X(glVertexAttribI4ui) \
@@ -444,6 +445,7 @@ pointers, sees the declarations without these aliases */
 #define glVertexAttribIFormat halo_glVertexAttribIFormat
 #define glVertexAttribBinding halo_glVertexAttribBinding
 #define glBindVertexBuffer halo_glBindVertexBuffer
+#define glBindTextures halo_glBindTextures
 #define glGetQueryBufferObjectuiv halo_glGetQueryBufferObjectuiv
 #define glVertexAttrib4fv halo_glVertexAttrib4fv
 #define glVertexAttribI4ui halo_glVertexAttribI4ui