M include/mgba/internal/ds/gx.h → include/mgba/internal/ds/gx.h

@@ -13,6 +13,7 @@
 #include <mgba/core/interface.h>
 #include <mgba/core/log.h>
 #include <mgba/core/timing.h>
+#include <mgba/internal/ds/matrix.h>
 #include <mgba-util/circle-buffer.h>
 
 mLOG_DECLARE_CATEGORY(DS_GX);
@@ -119,10 +120,24 @@
 	int outstandingParams[4];
 	uint8_t outstandingCommand[4];
 
+	int activeParams;
+	int activeEntries[32];
+
 	bool swapBuffers;
 	int bufferIndex;
 	struct DSGXVertex* vertexBuffer[2];
 	struct DSGXPolygon* polygonBuffer[2];
+
+	int mtxMode;
+	struct DSGXMatrix projMatrixStack;
+	struct DSGXMatrix texMatrixStack;
+	struct DSGXMatrix posMatrixStack[32];
+	struct DSGXMatrix vecMatrixStack[32];
+
+	struct DSGXMatrix projMatrix;
+	struct DSGXMatrix texMatrix;
+	struct DSGXMatrix posMatrix;
+	struct DSGXMatrix vecMatrix;
 };
 
 void DSGXInit(struct DSGX*);

A include/mgba/internal/ds/matrix.h

@@ -0,0 +1,21 @@
+/* Copyright (c) 2013-2017 Jeffrey Pfau
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#ifndef DS_MATRIX_H
+#define DS_MATRIX_H
+
+#include <mgba-util/common.h>
+
+CXX_GUARD_START
+
+struct DSGXMatrix {
+	int32_t m[16]; // 20.12
+};
+
+void DSGXMtxIdentity(struct DSGXMatrix*);
+
+CXX_GUARD_END
+
+#endif

M src/ds/gx.c → src/ds/gx.c

@@ -145,6 +145,10 @@ if (gx->swapBuffers) {
 			break;
 		}
 
+		DSRegGXSTAT gxstat = gx->p->memory.io9[DS9_REG_GXSTAT_LO >> 1];
+		int pvMatrixPointer = DSRegGXSTATGetPVMatrixStackLevel(gxstat);
+		int projMatrixPointer = DSRegGXSTATGetProjMatrixStackLevel(gxstat);
+
 		if (CircleBufferSize(&gx->pipe) <= 2 * sizeof(struct DSGXEntry)) {
 			_pullPipe(gx);
 		}
@@ -165,6 +169,71 @@ CircleBufferRead8(&gx->pipe, (int8_t*) &entry.params[2]);
 		CircleBufferRead8(&gx->pipe, (int8_t*) &entry.params[3]);
 
 		switch (entry.command) {
+		case DS_GX_CMD_MTX_MODE:
+			if (entry.params[0] < 4) {
+				gx->mtxMode = entry.params[0];
+			} else {
+				mLOG(DS_GX, GAME_ERROR, "Invalid GX MTX_MODE %02X", entry.params[0]);
+			}
+			break;
+		case DS_GX_CMD_MTX_IDENTITY:
+			switch (gx->mtxMode) {
+			case 0:
+				DSGXMtxIdentity(&gx->projMatrix);
+				break;
+			case 2:
+				DSGXMtxIdentity(&gx->vecMatrix);
+				// Fall through
+			case 1:
+				DSGXMtxIdentity(&gx->posMatrix);
+				break;
+			case 3:
+				DSGXMtxIdentity(&gx->texMatrix);
+				break;
+			}
+			break;
+		case DS_GX_CMD_MTX_PUSH:
+			switch (gx->mtxMode) {
+			case 0:
+				memcpy(&gx->projMatrixStack, &gx->projMatrix, sizeof(gx->projMatrix));
+				++projMatrixPointer;
+				break;
+			case 2:
+				memcpy(&gx->vecMatrixStack[pvMatrixPointer & 0x1F], &gx->vecMatrix, sizeof(gx->vecMatrix));
+				// Fall through
+			case 1:
+				memcpy(&gx->posMatrixStack[pvMatrixPointer & 0x1F], &gx->posMatrix, sizeof(gx->posMatrix));
+				++pvMatrixPointer;
+				break;
+			case 3:
+				mLOG(DS_GX, STUB, "Unimplemented GX MTX_PUSH mode");
+				break;
+			}
+			break;
+		case DS_GX_CMD_MTX_POP: {
+			int8_t offset = entry.params[0];
+			offset <<= 2;
+			offset >>= 2;
+			switch (gx->mtxMode) {
+			case 0:
+				projMatrixPointer -= offset;
+				memcpy(&gx->projMatrix, &gx->projMatrixStack, sizeof(gx->projMatrix));
+				break;
+			case 1:
+				pvMatrixPointer -= offset;
+				memcpy(&gx->posMatrix, &gx->posMatrixStack[pvMatrixPointer & 0x1F], sizeof(gx->posMatrix));
+				break;
+			case 2:
+				pvMatrixPointer -= offset;
+				memcpy(&gx->vecMatrix, &gx->vecMatrixStack[pvMatrixPointer & 0x1F], sizeof(gx->vecMatrix));
+				memcpy(&gx->posMatrix, &gx->posMatrixStack[pvMatrixPointer & 0x1F], sizeof(gx->posMatrix));
+				break;
+			case 3:
+				mLOG(DS_GX, STUB, "Unimplemented GX MTX_POP mode");
+				break;
+			}
+			break;
+		}
 		case DS_GX_CMD_SWAP_BUFFERS:
 			gx->swapBuffers = true;
 			break;
@@ -172,6 +241,12 @@ default:
 			mLOG(DS_GX, STUB, "Unimplemented GX command %02X:%02X %02X %02X %02X", entry.command, entry.params[0], entry.params[1], entry.params[2], entry.params[3]);
 			break;
 		}
+
+		gxstat = DSRegGXSTATSetPVMatrixStackLevel(gxstat, pvMatrixPointer);
+		gxstat = DSRegGXSTATSetProjMatrixStackLevel(gxstat, projMatrixPointer);
+		gxstat = DSRegGXSTATTestFillMatrixStackError(gxstat, projMatrixPointer || pvMatrixPointer >= 0x1F);
+		gx->p->memory.io9[DS9_REG_GXSTAT_LO >> 1] = gxstat;
+
 		if (cyclesLate >= cycles) {
 			cyclesLate -= cycles;
 		}
@@ -205,7 +280,22 @@
 void DSGXReset(struct DSGX* gx) {
 	CircleBufferClear(&gx->fifo);
 	CircleBufferClear(&gx->pipe);
+	DSGXMtxIdentity(&gx->projMatrix);
+	DSGXMtxIdentity(&gx->texMatrix);
+	DSGXMtxIdentity(&gx->posMatrix);
+	DSGXMtxIdentity(&gx->vecMatrix);
+
+	DSGXMtxIdentity(&gx->projMatrixStack);
+	DSGXMtxIdentity(&gx->texMatrixStack);
+	int i;
+	for (i = 0; i < 32; ++i) {
+		DSGXMtxIdentity(&gx->posMatrixStack[i]);
+		DSGXMtxIdentity(&gx->vecMatrixStack[i]);
+	}
 	gx->swapBuffers = false;
+	gx->bufferIndex = 0;
+	gx->mtxMode = 0;
+
 	memset(gx->outstandingParams, 0, sizeof(gx->outstandingParams));
 	memset(gx->outstandingCommand, 0, sizeof(gx->outstandingCommand));
 }

A src/ds/matrix.c

@@ -0,0 +1,16 @@
+/* Copyright (c) 2013-2017 Jeffrey Pfau
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+#include <mgba/internal/ds/matrix.h>
+
+#define MTX_ONE 0x00001000
+
+void DSGXMtxIdentity(struct DSGXMatrix* mtx) {
+	memset(mtx, 0, sizeof(*mtx));
+	mtx->m[0] = MTX_ONE;
+	mtx->m[5] = MTX_ONE;
+	mtx->m[10] = MTX_ONE;
+	mtx->m[15] = MTX_ONE;
+}