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@wwylele
Created March 13, 2018 11:15
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shadow map sampling
#include <3ds.h>
#include <stdio.h>
#include <citro3d.h>
#include <string.h>
#include "vshader_shbin.h"
#define CLEAR_COLOR 0x68B0D8FF
#define DISPLAY_TRANSFER_FLAGS \
(GX_TRANSFER_FLIP_VERT(0) | GX_TRANSFER_OUT_TILED(0) | GX_TRANSFER_RAW_COPY(0) | \
GX_TRANSFER_IN_FORMAT(GX_TRANSFER_FMT_RGBA8) | GX_TRANSFER_OUT_FORMAT(GX_TRANSFER_FMT_RGB8) | \
GX_TRANSFER_SCALING(GX_TRANSFER_SCALE_NO))
typedef struct { float x, y, z; } vertex;
static const vertex vertex_list[] =
{
{ 200.0f, 200.0f, 0.5f },
{ 100.0f, 40.0f, 0.5f },
{ 300.0f, 40.0f, 0.5f },
};
#define vertex_list_count (sizeof(vertex_list)/sizeof(vertex_list[0]))
static DVLB_s* vshader_dvlb;
static shaderProgram_s program;
static int uLoc_projection, uLoc_texcoord;
static C3D_Mtx projection;
static void* vbo_data;
C3D_Tex tex;
void FillTex(u32 color) {
u32* data = tex.data;
for (unsigned i = 0; i < 8 * 8; ++i) {
data[i] = color;
}
GSPGPU_FlushDataCache(data, 8 * 8 * 4);
}
void FillTexShadow(float d, float s) {
u32 D = d * 0xFFFFFF;
u8 S = s * 0xFF;
u32 color = (u32)S << 24;
color |= (D & 0xFF) << 16;
color |= (D & 0xFF00);
color |= (D & 0xFF0000) >> 16;
FillTex(color);
}
float xTexZ = 0.8f, xBias = 0.2f;
static void sceneInit(void)
{
// Load the vertex shader, create a shader program and bind it
vshader_dvlb = DVLB_ParseFile((u32*)vshader_shbin, vshader_shbin_size);
shaderProgramInit(&program);
shaderProgramSetVsh(&program, &vshader_dvlb->DVLE[0]);
C3D_BindProgram(&program);
// Get the location of the uniforms
uLoc_projection = shaderInstanceGetUniformLocation(program.vertexShader, "projection");
uLoc_texcoord = shaderInstanceGetUniformLocation(program.vertexShader, "texcoord");
// Configure attributes for use with the vertex shader
C3D_AttrInfo* attrInfo = C3D_GetAttrInfo();
AttrInfo_Init(attrInfo);
AttrInfo_AddLoader(attrInfo, 0, GPU_FLOAT, 3); // v0=position
AttrInfo_AddFixed(attrInfo, 1); // v1=color
// Set the fixed attribute (color) to solid white
C3D_FixedAttribSet(1, 1.0, 1.0, 1.0, 1.0);
// Compute the projection matrix
Mtx_OrthoTilt(&projection, 0.0, 400.0, 0.0, 240.0, 0.0, 1.0, true);
// Create the VBO (vertex buffer object)
vbo_data = linearAlloc(sizeof(vertex_list));
memcpy(vbo_data, vertex_list, sizeof(vertex_list));
// Configure buffers
C3D_BufInfo* bufInfo = C3D_GetBufInfo();
BufInfo_Init(bufInfo);
BufInfo_Add(bufInfo, vbo_data, sizeof(vertex), 1, 0x0);
// Configure the first fragment shading substage to just pass through the vertex color
// See https://www.opengl.org/sdk/docs/man2/xhtml/glTexEnv.xml for more insight
C3D_TexEnv* env = C3D_GetTexEnv(0);
C3D_TexEnvSrc(env, C3D_Both, GPU_TEXTURE0, 0, 0);
C3D_TexEnvOp(env, C3D_Both, 0, 0, 0);
C3D_TexEnvFunc(env, C3D_Both, GPU_REPLACE);
//C3D_TexInitShadow(&tex, 8, 8);
C3D_TexInitWithParams(&tex, NULL,
(C3D_TexInitParams){ 8, 8, 0, GPU_RGBA8, GPU_TEX_SHADOW_2D, false });
C3D_TexBind(0, &tex);
FillTexShadow(0.7, 0.6);
}
static void sceneRender(void)
{
// Update the uniforms
C3D_FVUnifMtx4x4(GPU_VERTEX_SHADER, uLoc_projection, &projection);
C3D_FVUnifSet(GPU_VERTEX_SHADER, uLoc_texcoord, 0.1f, 0.1f, xTexZ, 0.0f);
C3D_TexShadowParams(false, xBias);
// Draw the VBO
C3D_DrawArrays(GPU_TRIANGLES, 0, vertex_list_count);
}
static void sceneExit(void)
{
// Free the VBO
linearFree(vbo_data);
// Free the shader program
shaderProgramFree(&program);
DVLB_Free(vshader_dvlb);
}
void updateText() {
consoleClear();
printf("TexZ = %f\n", xTexZ);
printf("Bias = %f\n", xBias);
}
static PrintConsole bottomScreen;
int main()
{
// Initialize graphics
gfxInitDefault();
consoleInit(GFX_BOTTOM, &bottomScreen);
consoleSelect(&bottomScreen);
gfxSetDoubleBuffering(GFX_BOTTOM, true);
C3D_Init(C3D_DEFAULT_CMDBUF_SIZE);
// Initialize the render target
C3D_RenderTarget* target = C3D_RenderTargetCreate(240, 400, GPU_RB_RGBA8, GPU_RB_DEPTH24_STENCIL8);
C3D_RenderTargetSetClear(target, C3D_CLEAR_ALL, CLEAR_COLOR, 0);
C3D_RenderTargetSetOutput(target, GFX_TOP, GFX_LEFT, DISPLAY_TRANSFER_FLAGS);
// Initialize the scene
sceneInit();
// Main loop
while (aptMainLoop())
{
hidScanInput();
// Respond to user input
u32 kDown = hidKeysDown();
if (kDown & KEY_START)
break; // break in order to return to hbmenu
if (kDown & KEY_A) {
xTexZ += 0.2f;
if (xTexZ > 2.0f)
xTexZ = -1.0f;
}
if (kDown & KEY_B) {
xBias += 0.2f;
if (xBias > 1.0f)
xBias = 0.0f;
}
// Render the scene
C3D_FrameBegin(C3D_FRAME_SYNCDRAW);
C3D_FrameDrawOn(target);
sceneRender();
C3D_FrameEnd(0);
static int k = 0;
if (k == 4)updateText();
++k;
k %= 8;
}
// Deinitialize the scene
sceneExit();
// Deinitialize graphics
C3D_Fini();
gfxExit();
return 0;
}
; Example PICA200 vertex shader
; Uniforms
.fvec projection[4]
; Constants
.constf myconst(0.0, 1.0, -1.0, 0.1)
.constf myconst2(0.3, 0.0, 0.0, 0.0)
.alias zeros myconst.xxxx ; Vector full of zeros
.alias ones myconst.yyyy ; Vector full of ones
; Outputs
.out outpos position
.out outclr color
.out tex texcoord0
.out texw texcoord0w
; Inputs (defined as aliases for convenience)
.alias inpos v0
.alias inclr v1
.bool test
.fvec texcoord
.proc main
; Force the w component of inpos to be 1.0
mov r0.xyz, inpos
mov r0.w, ones
; outpos = projectionMatrix * inpos
dp4 outpos.x, projection[0], r0
dp4 outpos.y, projection[1], r0
dp4 outpos.z, projection[2], r0
dp4 outpos.w, projection[3], r0
; outclr = inclr
mov outclr, inclr
mov tex, texcoord
mov texw, texcoord.zzzz
; We're finished
end
.end
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