Render to texture

Author: fjtrujy

CMakeLists.txt

@@ -111,6 +111,7 @@ add_object_library_macros(GS_CORE_OBJS ee/gs/src/gsCore.c
 	gsKit_vram_clear
 	gsKit_sync_flip
 	gsKit_setactive
+	gsKit_renderToScreen
 	gsKit_finish
 	gsKit_lock_buffer
 	gsKit_unlock_buffer
@@ -216,6 +217,7 @@ add_object_library_macros(GS_TEXTURE_OBJS ee/gs/src/gsTexture.c
 	gsKit_texture_send
 	gsKit_texture_send_inline
 	gsKit_texture_upload
+	gsKit_renderToTexture
 	gsKit_prim_sprite_texture_3d
 	gsKit_prim_sprite_striped_texture_3d
 	gsKit_prim_triangle_texture_3d
@@ -361,6 +363,7 @@ if(NOT SKIP_BUILD_EXAMPLES)
 		modetest
 		modetesthires
 		pixelperfect
+		rendertexture
 		texstream
 		textures
 		vsync

ee/gs/include/gsCore.h

@@ -128,6 +128,9 @@ void gsKit_switch_context(GSGLOBAL *gsGlobal);
 /// Sets Your Active Framebuffer
 void gsKit_setactive(GSGLOBAL *gsGlobal);
 
+/// Set the render target to the current screen buffer
+void gsKit_renderToScreen(GSGLOBAL *gsGlobal);
+
 /// Blocks until FINISH is triggered
 void gsKit_finish(void);
 

ee/gs/include/gsTexture.h

@@ -117,6 +117,7 @@ void gsKit_texture_to_psm16(GSTEXTURE *Texture);
 void gsKit_texture_send(u32 *mem, int width, int height, u32 tbp, u32 psm, u32 tbw, u8 clut);
 void gsKit_texture_send_inline(GSGLOBAL *gsGlobal, u32 *mem, int width, int height, u32 tbp, u32 psm, u32 tbw, u8 clut);
 void gsKit_texture_upload(GSGLOBAL *gsGlobal, GSTEXTURE *Texture);
+void gsKit_renderToTexture(GSGLOBAL *gsGlobal, GSTEXTURE *texture);
 
 void gsKit_prim_sprite_texture_3d(GSGLOBAL *gsGlobal, const GSTEXTURE *Texture, float x1, float y1, int iz1, float u1, float v1,
                                                                        float x2, float y2, int iz2, float u2, float v2,

ee/gs/src/gsCore.c

@@ -120,6 +120,27 @@ void gsKit_setactive(GSGLOBAL *gsGlobal)
 }
 #endif
 
+#if F_gsKit_renderToScreen
+void gsKit_renderToScreen(GSGLOBAL *gsGlobal)
+{
+	u64 *p_data;
+	u64 *p_store;
+	int qsize = 1;
+
+	p_store = p_data = gsKit_heap_alloc(gsGlobal, qsize, (qsize*16), GIF_AD);
+
+	if(p_store == gsGlobal->CurQueue->last_tag)
+	{
+		*p_data++ = GIF_TAG_AD(qsize);
+		*p_data++ = GIF_AD;
+	}
+
+	*p_data++ = GS_SETREG_FRAME_1( gsGlobal->ScreenBuffer[gsGlobal->ActiveBuffer & 1] / 8192,
+                                 gsGlobal->Width / 64, gsGlobal->PSM, 0 );
+	*p_data++ = GS_FRAME_1;
+}
+#endif
+
 #if F_gsKit_finish
 void gsKit_finish(void)
 {

ee/gs/src/gsTexture.c

@@ -522,6 +522,27 @@ void gsKit_prim_sprite_texture_3d(GSGLOBAL *gsGlobal, const GSTEXTURE *Texture,
 }
 #endif
 
+#if F_gsKit_renderToTexture
+void gsKit_renderToTexture(GSGLOBAL *gsGlobal, GSTEXTURE *texture)
+{
+	u64 *p_data;
+	u64 *p_store;
+	int qsize = 1;
+
+	p_store = p_data = gsKit_heap_alloc(gsGlobal, qsize, (qsize*16), GIF_AD);
+
+	if(p_store == gsGlobal->CurQueue->last_tag)
+	{
+		*p_data++ = GIF_TAG_AD(qsize);
+		*p_data++ = GIF_AD;
+	}
+
+	*p_data++ = GS_SETREG_FRAME_1(texture->Vram / 8192,
+                                 texture->Width / 64, texture->PSM, 0 );
+	*p_data++ = GS_FRAME_1;
+}
+#endif
+
 #if F_gsKit_prim_sprite_striped_texture_3d
 void gsKit_prim_sprite_striped_texture_3d(GSGLOBAL *gsGlobal, const GSTEXTURE *Texture,
 				float x1, float y1, int iz1, float u1, float v1,

examples/rendertexture/rendertexture.c

@@ -0,0 +1,97 @@
+//  ____     ___ |    / _____ _____
+// |  __    |    |___/    |     |
+// |___| ___|    |    \ __|__   |     gsKit Open Source Project.
+// ----------------------------------------------------------------------
+// Copyright 2004 - Chris "Neovanglist" Gilbert <[email protected]>
+// Licenced under Academic Free License version 2.0
+// Review gsKit README & LICENSE files for further details.
+//
+// renderTexture.c - Example demonstrating render to texture operation.
+// First we are rendering a triangle to a texture, 
+// then we are rendering the texture to the screen.
+//
+
+#include <stdio.h>
+#include <malloc.h>
+
+#include <gsKit.h>
+#include <dmaKit.h>
+#include <gsToolkit.h>
+#include <gsInline.h>
+#include <gsTexture.h>
+
+#define TEXTURE_WIDTH 256
+#define TEXTURE_HEIGHT 256
+
+int main(int argc, char *argv[])
+{
+	GSGLOBAL *gsGlobal;
+	GSTEXTURE renderTexture;
+	uint32_t i, j, offset;
+	uint32_t totalVertices = 3;
+	uint32_t textureTotalVertices = 2;
+	uint64_t White = GS_SETREG_RGBAQ(0xFF, 0xFF, 0xFF, 0x00, 0x00);
+	gs_rgbaq color = color_to_RGBAQ(0x80, 0x80, 0x80, 0x80, 0);
+	u32 render_target_ptr;
+
+	gsGlobal = gsKit_init_global();
+
+	gsGlobal->PSM = GS_PSM_CT24;
+	gsGlobal->PSMZ = GS_PSMZ_16S;
+
+	dmaKit_init(D_CTRL_RELE_OFF, D_CTRL_MFD_OFF, D_CTRL_STS_UNSPEC,
+				D_CTRL_STD_OFF, D_CTRL_RCYC_8, 1 << DMA_CHANNEL_GIF);
+
+	// Initialize the DMAC
+	dmaKit_chan_init(DMA_CHANNEL_GIF);
+
+	gsKit_init_screen(gsGlobal);
+	gsKit_mode_switch(gsGlobal, GS_ONESHOT);
+
+	renderTexture.Width = TEXTURE_WIDTH;
+	renderTexture.Height = TEXTURE_HEIGHT;
+	renderTexture.PSM = GS_PSM_CT16;
+	renderTexture.Mem = 0; // NOT NEEDED
+	renderTexture.Vram = gsKit_vram_alloc(gsGlobal, gsKit_texture_size(renderTexture.Width, renderTexture.Height, renderTexture.PSM), GSKIT_ALLOC_USERBUFFER);
+
+	gsKit_set_clamp(gsGlobal, GS_CMODE_CLAMP);
+
+	GSPRIMPOINT *verts = (GSPRIMPOINT *)malloc(sizeof(GSPRIMPOINT) * totalVertices);
+	verts[0].xyz2 = vertex_to_XYZ2(gsGlobal, 0, 0, 0);
+	verts[0].rgbaq = color_to_RGBAQ(0xFF, 0x00, 0x00, 0xFF, 0);
+
+	verts[1].xyz2 = vertex_to_XYZ2(gsGlobal, renderTexture.Width, 0, 0);
+	verts[1].rgbaq = color_to_RGBAQ(0x00, 0xFF, 0x00, 0xFF, 0);
+
+	verts[2].xyz2 = vertex_to_XYZ2(gsGlobal, renderTexture.Width / 2, renderTexture.Height, 0);
+	verts[2].rgbaq = color_to_RGBAQ(0x00, 0x00, 0xFF, 0xFF, 0);
+
+	GSPRIMUVPOINTFLAT *textureVertex = (GSPRIMUVPOINTFLAT *)malloc(sizeof(GSPRIMUVPOINTFLAT) * textureTotalVertices);
+	textureVertex[0].xyz2 = vertex_to_XYZ2(gsGlobal, 0, 0, 0);
+	textureVertex[0].uv = vertex_to_UV(&renderTexture, 0, 0);
+
+	textureVertex[1].xyz2 = vertex_to_XYZ2(gsGlobal, gsGlobal->Width, gsGlobal->Height, 0);
+	textureVertex[1].uv = vertex_to_UV(&renderTexture, renderTexture.Width, renderTexture.Height);
+
+	while (1)
+	{
+		gsKit_clear(gsGlobal, White);
+		
+		// set render target to the texture
+		gsKit_renderToTexture(gsGlobal, &renderTexture);
+
+		gsKit_prim_list_triangle_gouraud_3d(gsGlobal, totalVertices, verts);
+
+		// set render target back to the screen
+		gsKit_renderToScreen(gsGlobal);
+
+		gskit_prim_list_sprite_texture_uv_flat_color(gsGlobal, &renderTexture, color, textureTotalVertices, textureVertex);
+
+		gsKit_queue_exec(gsGlobal);
+		gsKit_sync_flip(gsGlobal);
+	}
+
+	free(verts);
+
+	return 0;
+}