Fix TIM compatibility and improve TIM validation.

PSn00bSDK is a good SDK for testing decompiled game code and working with extracted TIM resources.
However, there is an issue where some textures that can be loaded with the PsyQ SDK
are not compatible with PSn00bSDK, causing a black screen when attempting to load them.
This commit fixes this issue.

Additionally, it adds a new check in the `GsGetTimInfo` and `GetTimInfo` functions.
The check verifies if pixel data exists before setting the corresponding fields in the structure,
preventing the loading of garbage data.

1 files changed, 35 insertions, 19 deletions

diff --git a/libpsn00b/psxgpu/image.c b/libpsn00b/psxgpu/image.c
index 3a2bb8f..e5024ce 100644
--- a/libpsn00b/psxgpu/image.c
+++ b/libpsn00b/psxgpu/image.c
@@ -29,13 +29,27 @@ static int  _next_saved_rect = 0;
 
 static void _dma_transfer(const RECT *rect, uint32_t *data, int write) {
 	size_t length = rect->w * rect->h;
+	size_t dma_chunk_lenght = DMA_CHUNK_LENGTH;
 	if (length % 2)
 		_sdk_log("can't transfer an odd number of pixels\n");
 
 	length /= 2;
-	if ((length >= DMA_CHUNK_LENGTH) && (length % DMA_CHUNK_LENGTH)) {
-		_sdk_log("transfer data length (%d) is not a multiple of %d, rounding\n", length, DMA_CHUNK_LENGTH);
-		length += DMA_CHUNK_LENGTH - 1;
+	if (length >= dma_chunk_lenght) {
+		uint32_t tail = length % dma_chunk_lenght;
+		if(tail) {
+			// index  length    w    h
+			// 0      80        5    16
+			// 1      34        2    17
+			// 2      36        6    6
+			// 3      38        2    19
+			// 4      40        5    8
+			// 5      42        6    7
+			// 6      44        11   4
+			// 7      46        23   2
+			uint8_t dma_chunk_length_lookup[8] = {8, 1, 2, 1, 4, 1, 2, 1};
+			dma_chunk_lenght = dma_chunk_length_lookup[tail % 8];
+			_sdk_log("transfer data length / 2 (%d) is not a multiple of %d, changing dma_chunk_lenght %d\n", length, DMA_CHUNK_LENGTH, dma_chunk_lenght);
+		}
 	}
 
 	while (!(GPU_GP1 & (1 << 26)))
@@ -66,11 +80,11 @@ static void _dma_transfer(const RECT *rect, uint32_t *data, int write) {
 		__asm__ volatile("");
 
 	DMA_MADR(DMA_GPU) = (uint32_t) data;
-	if (length < DMA_CHUNK_LENGTH)
+	if (length < dma_chunk_lenght)
 		DMA_BCR(DMA_GPU) = 0x00010000 | length;
 	else
-		DMA_BCR(DMA_GPU) = DMA_CHUNK_LENGTH |
-			((length / DMA_CHUNK_LENGTH) << 16);
+		DMA_BCR(DMA_GPU) = dma_chunk_lenght |
+			((length / dma_chunk_lenght) << 16);
 
 	DMA_CHCR(DMA_GPU) = 0x01000200 | write;
 }
@@ -169,6 +183,7 @@ int GsGetTimInfo(const uint32_t *tim, GsIMAGE *info) {
 	if ((*(tim++) & 0xffff) != 0x0010)
 		return 1;
 
+	*info = (GsIMAGE){0};
 	info->pmode = *(tim++);
 	if (info->pmode & 8) {
 		const uint32_t *palette_end = tim;
@@ -179,15 +194,15 @@ int GsGetTimInfo(const uint32_t *tim, GsIMAGE *info) {
 		info->clut = (uint32_t *) tim;
 
 		tim = palette_end;
-	} else {
-		info->clut = 0;
 	}
 
-	tim++;
-	*((uint32_t *) &(info->px)) = *(tim++);
-	*((uint32_t *) &(info->pw)) = *(tim++);
-	info->pixel = (uint32_t *) tim;
-
+	uint32_t plenght = *(tim++);
+	// bnum(4 bytes) + pos(4 bytes) + size(4 bytes)
+	if (plenght > 12) {
+		*((uint32_t *) &(info->px)) = *(tim++);
+		*((uint32_t *) &(info->pw)) = *(tim++);
+		info->pixel = (uint32_t *) tim;
+	}
 	return 0;
 }
 
@@ -197,6 +212,7 @@ int GetTimInfo(const uint32_t *tim, TIM_IMAGE *info) {
 	if ((*(tim++) & 0xffff) != 0x0010)
 		return 1;
 
+	*info = (TIM_IMAGE){0};
 	info->mode = *(tim++);
 	if (info->mode & 8) {
 		const uint32_t *palette_end = tim;
@@ -206,13 +222,13 @@ int GetTimInfo(const uint32_t *tim, TIM_IMAGE *info) {
 		info->caddr = (uint32_t *) &tim[2];
 
 		tim = palette_end;
-	} else {
-		info->caddr = 0;
 	}
 
-	tim++;
-	info->prect = (RECT *)     tim;
-	info->paddr = (uint32_t *) &tim[2];
-
+	uint32_t plenght = *(tim++);
+	// bnum(4 bytes) + pos(4 bytes) + size(4 bytes)
+	if(plenght > 12) {
+		info->prect = (RECT *)     tim;
+		info->paddr = (uint32_t *) &tim[2];
+	}
 	return 0;
 }