Graphics Samples

The graphics samples demonstrate the RSX (Reality Synthesizer) graphics processor, 3D rendering with shaders, texture mapping, and 2D graphics using Cairo.

Available Graphics Samples

rsxtest

Basic 3D rendering with vertex and fragment shaders

rsxtest_spu

RSX rendering with SPU-assisted vertex processing

cairo

2D vector graphics using Cairo library

pngtest

PNG image loading and display

jpgtest

JPEG image loading and display

blitting

Surface blitting and buffer operations

rsxtest_dl

Display list based rendering

rsxtest_flip

Buffer flipping and vsync

rsxtest - 3D Graphics Fundamentals

Location: samples/graphics/rsxtest/ Demonstrates complete 3D rendering pipeline with diffuse and specular lighting.

What It Demonstrates

RSX context initialization
Vertex and fragment shader loading
3D mesh creation (sphere, donut, cube)
Texture mapping
Lighting calculations (diffuse + specular)
Double buffering and vsync

Key Code: Initialization

samples/graphics/rsxtest/source/main.cpp

int main(int argc, const char *argv[])
{
    padInfo padinfo;
    padData paddata;
    void *host_addr = memalign(HOST_ADDR_ALIGNMENT, HOSTBUFFER_SIZE);

    printf("rsxtest starting...\n");

    // Initialize screen and RSX context
    init_screen(host_addr, HOSTBUFFER_SIZE);
    ioPadInit(7);
    
    // Load shaders
    init_shader();
    
    // Initialize texture
    init_texture();

    // Create 3D meshes
    sphere = createSphere(3.0f, 32, 32);
    donut = createDonut(3.0f, 1.5f, 32, 32);
    cube = createCube(5.0f);

    // Setup callbacks
    atexit(program_exit_callback);
    sysUtilRegisterCallback(0, sysutil_exit_callback, NULL);

    // Create projection matrix
    P = transpose(Matrix4::perspective(DEGTORAD(45.0f), aspect_ratio, 1.0f, 3000.0f));

    setDrawEnv();
    setRenderTarget(curr_fb);

    running = 1;
    while(running) {
        sysUtilCheckCallback();
        
        // Check for controller input
        ioPadGetInfo(&padinfo);
        for(int i = 0; i < MAX_PADS; i++) {
            if(padinfo.status[i]) {
                ioPadGetData(i, &paddata);
                if(paddata.BTN_CROSS)
                    goto done;
            }
        }
        
        drawFrame();
        flip();
    }

done:
    printf("rsxtest done...\n");
    program_exit_callback();
    return 0;
}

Drawing Pipeline

The rendering process:

Set viewport and clear

Configure viewport, scissor region, and clear buffers

Set draw state

Enable depth testing, set culling mode, configure blending

Load shaders

Load vertex and fragment programs with their parameters

Bind vertex data

Bind vertex positions, normals, and texture coordinates

Set shader uniforms

Pass matrices, lighting parameters, material properties

Draw geometry

Issue draw calls for each mesh using indexed triangles

Shader Setup

void init_shader()
{
    u32 fpsize = 0;
    u32 vpsize = 0;

    // Get vertex shader code
    rsxVertexProgramGetUCode(vpo, &vp_ucode, &vpsize);
    
    // Get shader constants
    projMatrix = rsxVertexProgramGetConst(vpo, "projMatrix");
    mvMatrix = rsxVertexProgramGetConst(vpo, "modelViewMatrix");

    // Get fragment shader code
    rsxFragmentProgramGetUCode(fpo, &fp_ucode, &fpsize);
    
    // Allocate fragment shader buffer in RSX memory
    fp_buffer = (u32*)rsxMemalign(64, fpsize);
    memcpy(fp_buffer, fp_ucode, fpsize);
    rsxAddressToOffset(fp_buffer, &fp_offset);

    // Get fragment shader parameters
    textureUnit = rsxFragmentProgramGetAttrib(fpo, "texture");
    eyePosition = rsxFragmentProgramGetConst(fpo, "eyePosition");
    globalAmbient = rsxFragmentProgramGetConst(fpo, "globalAmbient");
    litPosition = rsxFragmentProgramGetConst(fpo, "lightPosition");
    litColor = rsxFragmentProgramGetConst(fpo, "lightColor");
    spec = rsxFragmentProgramGetConst(fpo, "shininess");
    Ks = rsxFragmentProgramGetConst(fpo, "Ks");
    Kd = rsxFragmentProgramGetConst(fpo, "Kd");
}

rsxtest_spu - SPU-Assisted Graphics

Location: samples/graphics/rsxtest_spu/ Combines RSX rendering with SPU vertex processing for improved performance.

What It Demonstrates

SPU vertex transformation
PPU-SPU data transfer
Workload distribution
Parallel processing benefits

cairo - 2D Vector Graphics

Location: samples/graphics/cairo/ Shows how to use the Cairo graphics library for 2D drawing.

What It Demonstrates

Cairo surface creation
Vector drawing primitives
Rotation and transformation
Real-time FPS display

Drawing with Cairo

samples/graphics/cairo/source/main.c

void drawFrame(rsxBuffer *buffer, int frame)
{
    cairo_t *cr;
    cairo_surface_t *surface = NULL;
    static time_t starttime = 0;
    double fps = 0;

    if (starttime == 0)
        starttime = time(NULL);
    else
        fps = frame / difftime(time(NULL), starttime);

    // Create Cairo surface from RSX buffer
    surface = cairo_image_surface_create_for_data(
        (u8 *)buffer->ptr,
        CAIRO_FORMAT_RGB24,
        buffer->width,
        buffer->height,
        buffer->width * 4
    );

    if (surface != NULL) {
        cr = cairo_create(surface);
        if (cr != NULL) {
            // Clear to white
            cairo_set_source_rgb(cr, 1.0, 1.0, 1.0);
            cairo_paint(cr);

            // Draw rotating square
            cairo_save(cr);
            cairo_new_path(cr);
            cairo_translate(cr, buffer->width / 2, buffer->height / 2);
            cairo_rotate(cr, frame * M_PI / 180);
            cairo_set_antialias(cr, CAIRO_ANTIALIAS_SUBPIXEL);
            
            int size = 100;
            cairo_line_to(cr, -(size / 2), -(size / 2));
            cairo_line_to(cr, -(size / 2), +(size / 2));
            cairo_line_to(cr, +(size / 2), +(size / 2));
            cairo_line_to(cr, +(size / 2), -(size / 2));
            cairo_close_path(cr);

            // Animated color
            float rel = sin((frame % 180) * M_PI / 180);
            float r = (rel < 0.5) ? 0.85 : 2 * (1.0 - rel);
            float g = (rel < 0.5) ? 2 * rel : 0.85;
            
            cairo_set_source_rgb(cr, r, g, 0);
            cairo_fill_preserve(cr);
            cairo_stroke(cr);

            // Display FPS
            cairo_identity_matrix(cr);
            cairo_set_source_rgb(cr, 0, 0, 0);
            cairo_select_font_face(cr, "Purisa",
                CAIRO_FONT_SLANT_NORMAL,
                CAIRO_FONT_WEIGHT_BOLD);
            cairo_set_font_size(cr, 13);
            cairo_move_to(cr, 50, 30);
            
            char buf[100];
            snprintf(buf, 100, "FPS : %f", fps);
            cairo_show_text(cr, buf);

            cairo_destroy(cr);
        }

        cairo_surface_finish(surface);
        cairo_surface_destroy(surface);
    }
}

Image Loading Samples

pngtest - PNG Images

Location: samples/graphics/pngtest/ Loads and displays PNG images using libpng.

jpgtest - JPEG Images

Location: samples/graphics/jpgtest/ Loads and displays JPEG images using libjpeg.

Building Graphics Samples

Build All Graphics Samples

cd samples/graphics
make

Build Individual Sample

cd samples/graphics/rsxtest
make

Clean

make clean

Common Patterns

RSX Initialization

Screen and context setup

void *host_addr = memalign(HOST_ADDR_ALIGNMENT, HOSTBUFFER_SIZE);
init_screen(host_addr, HOSTBUFFER_SIZE);

Allocates aligned memory for RSX command buffer and initializes the display.

Shader loading

rsxVertexProgramGetUCode(vpo, &vp_ucode, &vpsize);
rsxFragmentProgramGetUCode(fpo, &fp_ucode, &fpsize);

Extracts compiled shader microcode from embedded shader programs.

Vertex binding

rsxAddressToOffset(&mesh->vertices[0].pos, &offset);
rsxBindVertexArrayAttrib(context, GCM_VERTEX_ATTRIB_POS, 0, offset,
    sizeof(S3DVertex), 3, GCM_VERTEX_DATA_TYPE_F32, GCM_LOCATION_RSX);

Binds vertex attribute arrays to shader inputs.

Buffer Management

// Set render target
setRenderTarget(curr_fb);

// Clear buffers
rsxSetClearColor(context, color);
rsxSetClearDepthStencil(context, 0xffffff00);
rsxClearSurface(context, GCM_CLEAR_R | GCM_CLEAR_G | GCM_CLEAR_B |
    GCM_CLEAR_A | GCM_CLEAR_S | GCM_CLEAR_Z);

// Flip after rendering
flip();

Performance Tips

Use RSX memory for frequently accessed data

Allocate vertex buffers, textures, and shader code in RSX memory using rsxMemalign() for best performance.

Minimize state changes

Group draw calls with similar render states together to reduce overhead.

Consider SPU assistance

For complex vertex processing, offload work to SPUs as shown in rsxtest_spu.

Use appropriate precision

Use half-precision floats in shaders where full precision isn’t needed.

RSX API Reference

Complete RSX graphics API documentation

Graphics Guide

In-depth graphics programming concepts

Shader Programming

Writing vertex and fragment shaders

SPU Samples

SPU programming for graphics acceleration

Sample Projects

Graphics Samples

Available Graphics Samples

rsxtest

rsxtest_spu

cairo

pngtest

jpgtest

blitting

rsxtest_dl

rsxtest_flip

rsxtest - 3D Graphics Fundamentals

What It Demonstrates

Key Code: Initialization

Drawing Pipeline

Shader Setup

rsxtest_spu - SPU-Assisted Graphics

What It Demonstrates

cairo - 2D Vector Graphics

What It Demonstrates

Drawing with Cairo

Image Loading Samples

pngtest - PNG Images

jpgtest - JPEG Images

Building Graphics Samples

Build All Graphics Samples

Build Individual Sample

Clean

Common Patterns

RSX Initialization

Buffer Management

Performance Tips

RSX API Reference

Graphics Guide

Shader Programming

SPU Samples

Build docs developers (and LLMs) love

Sample Projects

​Available Graphics Samples

rsxtest

rsxtest_spu

cairo

pngtest

jpgtest

blitting

rsxtest_dl

rsxtest_flip

​rsxtest - 3D Graphics Fundamentals

​What It Demonstrates

​Key Code: Initialization

​Drawing Pipeline

​Shader Setup

​rsxtest_spu - SPU-Assisted Graphics

​What It Demonstrates

​cairo - 2D Vector Graphics

​What It Demonstrates

​Drawing with Cairo

​Image Loading Samples

​pngtest - PNG Images

​jpgtest - JPEG Images

​Building Graphics Samples

​Build All Graphics Samples

​Build Individual Sample

​Clean

​Common Patterns

​RSX Initialization

​Buffer Management

​Performance Tips

​Related Documentation

RSX API Reference

Graphics Guide

Shader Programming

SPU Samples

Build docs developers (and LLMs) love

Available Graphics Samples

rsxtest - 3D Graphics Fundamentals

What It Demonstrates

Key Code: Initialization

Drawing Pipeline

Shader Setup

rsxtest_spu - SPU-Assisted Graphics

What It Demonstrates

cairo - 2D Vector Graphics

What It Demonstrates

Drawing with Cairo

Image Loading Samples

pngtest - PNG Images

jpgtest - JPEG Images

Building Graphics Samples

Build All Graphics Samples

Build Individual Sample

Clean

Common Patterns

RSX Initialization

Buffer Management

Performance Tips

Related Documentation