From 26c9a454e48cb1f8feb98b2c64f622185a31254c Mon Sep 17 00:00:00 2001
From: Luke Benstead <kazade@gmail.com>
Date: Wed, 21 Apr 2021 15:34:28 +0100
Subject: [PATCH] More performance work

---
 GL/draw.c          | 68 +++++++++++++++++++++++++++-------------------
 GL/platforms/sh4.h | 19 +++++++++++++
 2 files changed, 59 insertions(+), 28 deletions(-)

diff --git a/GL/draw.c b/GL/draw.c
index 7350324..5491e39 100644
--- a/GL/draw.c
+++ b/GL/draw.c
@@ -797,40 +797,49 @@ static void generateArraysFastPath(SubmissionTarget* target, const GLsizei first
 
 
     /* Copy the pos, uv and color directly in one go */
-    const GLubyte* pos = VERTEX_POINTER.ptr + (first * vstride);
-    const GLubyte* uv = UV_POINTER.ptr + (first * uvstride);
-    const GLubyte* col = DIFFUSE_POINTER.ptr + (first * dstride);
-    const GLubyte* st = ST_POINTER.ptr + (first * ststride);
-    const GLubyte* n = NORMAL_POINTER.ptr + (first * nstride);
-
-    typedef struct {
-        float x, y, z;
-    } V3;
-
-    typedef struct {
-        float u, v;
-    } V2;
+    const GLubyte* pos = (ENABLED_VERTEX_ATTRIBUTES & VERTEX_ENABLED_FLAG) ? VERTEX_POINTER.ptr + (first * vstride) : NULL;
+    const GLubyte* uv = (ENABLED_VERTEX_ATTRIBUTES & UV_ENABLED_FLAG) ? UV_POINTER.ptr + (first * uvstride) : NULL;
+    const GLubyte* col = (ENABLED_VERTEX_ATTRIBUTES & DIFFUSE_ENABLED_FLAG) ? DIFFUSE_POINTER.ptr + (first * dstride) : NULL;
+    const GLubyte* st = (ENABLED_VERTEX_ATTRIBUTES & ST_ENABLED_FLAG) ? ST_POINTER.ptr + (first * ststride) : NULL;
+    const GLubyte* n = (ENABLED_VERTEX_ATTRIBUTES & NORMAL_ENABLED_FLAG) ? NORMAL_POINTER.ptr + (first * nstride) : NULL;
 
     VertexExtra* ve = aligned_vector_at(target->extras, 0);
     Vertex* it = start;
-    ITERATE(count) {
+
+    const float w = 1.0f;
+
+    uint32_t i = count;
+
+    while(i--) {
         it->flags = GPU_CMD_VERTEX;
 
-        *((V3*) it->xyz) = *((V3*) pos);
-        *((V2*) it->uv) = *((V2*) uv);
-        *((uint32_t*) it->bgra) = *((uint32_t*) col);
+        if(pos) {
+            TransformVertex((const float*) pos, &w, it->xyz, &it->w);
+            pos += vstride;
+        }
 
-        *((V2*) ve->st) = *((V2*) st);
-        *((V3*) ve->nxyz) = *((V3*) n);
+        if(uv) {
+            MEMCPY4(it->uv, uv, sizeof(float) * 2);
+            uv += uvstride;
+        }
+
+        if(col) {
+            MEMCPY4(it->bgra, col, sizeof(uint32_t));
+            col += dstride;
+        }
+
+        if(st) {
+            MEMCPY4(ve->st, st, sizeof(float) * 2);
+            st += ststride;
+        }
+
+        if(n) {
+            MEMCPY4(ve->nxyz, n, sizeof(float) * 3);
+            n += nstride;
+        }
 
         it++;
         ve++;
-
-        pos += vstride;
-        uv += uvstride;
-        col += dstride;
-        st += ststride;
-        n += nstride;
     }
 }
 
@@ -890,8 +899,6 @@ static void transform(SubmissionTarget* target) {
     /* Perform modelview transform, storing W */
     Vertex* vertex = _glSubmissionTargetStart(target);
 
-    _glApplyRenderMatrix(); /* Apply the Render Matrix Stack */
-
     TransformVertices(vertex, target->count);
 }
 
@@ -1095,13 +1102,18 @@ GL_FORCE_INLINE void submitVertices(GLenum mode, GLsizei first, GLuint count, GL
 
     /* Make room for the vertices and header */
     aligned_vector_extend(&target->output->vector, target->count + 1);
+
+    _glApplyRenderMatrix(); /* Apply the Render Matrix Stack */
+
     generate(target, mode, first, count, (GLubyte*) indices, type);
 
     if(doLighting){
         light(target);
     }
 
-    transform(target);
+    if(!FAST_PATH_ENABLED) {
+        transform(target);
+    }
 
     if(_glIsClippingEnabled()) {
 #if DEBUG_CLIPPING
diff --git a/GL/platforms/sh4.h b/GL/platforms/sh4.h
index d84b25e..b1b6823 100644
--- a/GL/platforms/sh4.h
+++ b/GL/platforms/sh4.h
@@ -69,6 +69,25 @@ inline void TransformVec4(float* x) {
 
 }
 
+static inline void TransformVertex(const float* xyz, const float* w, float* oxyz, float* ow) {
+    register float __x __asm__("fr12") = (xyz[0]);
+    register float __y __asm__("fr13") = (xyz[1]);
+    register float __z __asm__("fr14") = (xyz[2]);
+    register float __w __asm__("fr15") = (*w);
+
+    __asm__ __volatile__(
+        "fldi1 fr15\n"
+        "ftrv   xmtrx,fv12\n"
+        : "=f" (__x), "=f" (__y), "=f" (__z), "=f" (__w)
+        : "0" (__x), "1" (__y), "2" (__z), "3" (__w)
+    );
+
+    oxyz[0] = __x;
+    oxyz[1] = __y;
+    oxyz[2] = __z;
+    *ow = __w;
+}
+
 static inline void TransformVertices(Vertex* vertices, const int count) {
     Vertex* it = vertices;
     for(int i = 0; i < count; ++i, ++it) {