merge pixpy repo into this repo

1 files changed, 169 insertions, 0 deletions

diff --git a/renderer.py b/renderer.py
new file mode 100644
index 0000000..ae4be12
--- /dev/null
+++ b/renderer.py
@@ -0,0 +1,169 @@
+import numpy as np
+from OpenGL.GL import *
+from OpenGL.GLUT import *
+from OpenGL.GLU import *
+from typing import Protocol
+
+class ImageRenderer:
+    def __init__(self):
+        # Setup shader and quad
+        self.shader = self._init_shader()
+        self.vao = self._init_quad()
+
+        # Get uniform locations from the shader
+        self.uTransform = glGetUniformLocation(self.shader, "uTransform")
+        self.uAlpha = glGetUniformLocation(self.shader, "uAlpha")
+
+        # Use the shader program and set default texture unit to 0
+        glUseProgram(self.shader)
+        glUniform1i(glGetUniformLocation(self.shader, "uTexture"), 0)
+
+        # Setup transition
+        self.transition = None
+
+    def set_transition(self, transition_cls):
+        self.transition = transition_cls(self)
+
+    @staticmethod
+    def compile_shader(source, shader_type):
+        shader = glCreateShader(shader_type)             # Create a new shader object
+        glShaderSource(shader, source)                   # Attach the shader source code
+        glCompileShader(shader)                          # Compile the shader
+        if not glGetShaderiv(shader, GL_COMPILE_STATUS): # Check if compilation succeeded
+            raise RuntimeError(glGetShaderInfoLog(shader).decode()) # Raise error with log if failed
+        return shader
+
+    @staticmethod
+    def _init_shader():
+        vertex_src = """
+        #version 330 core
+        layout (location = 0) in vec2 aPos;      // Vertex position
+        layout (location = 1) in vec2 aTexCoord; // Texture coordinates
+        uniform mat4 uTransform;                 // Transformation matrix
+        out vec2 TexCoord;                       // Output texture coordinate
+
+        void main() {
+            gl_Position = uTransform * vec4(aPos, 0.0, 1.0); // Apply transformation
+            TexCoord = aTexCoord;                            // Pass tex coord to fragment shader
+        }
+        """
+        fragment_src = """
+        #version 330 core
+        in vec2 TexCoord;           // Interpolated texture coordinates
+        out vec4 FragColor;         // Final fragment color
+        uniform sampler2D uTexture; // Texture sampler
+        uniform float uAlpha;       // Global alpha for transparency
+
+        void main() {
+            vec4 texColor = texture(uTexture, TexCoord);         // Sample texture
+            FragColor = vec4(texColor.rgb, texColor.a * uAlpha); // Apply alpha blending
+        }
+        """
+
+        # Compile and link shaders into a program
+        vs = ImageRenderer.compile_shader(vertex_src, GL_VERTEX_SHADER)
+        fs = ImageRenderer.compile_shader(fragment_src, GL_FRAGMENT_SHADER)
+        prog = glCreateProgram()
+        glAttachShader(prog, vs)
+        glAttachShader(prog, fs)
+        glLinkProgram(prog)
+        return prog
+
+    @staticmethod
+    def _init_quad():
+        # Define a full-screen quad with positions and texture coordinates
+        quad = np.array([
+            -1, -1,  0, 0,  # Bottom-left
+             1, -1,  1, 0,  # Bottom-right
+            -1,  1,  0, 1,  # Top-left
+             1,  1,  1, 1,  # Top-right
+        ], dtype=np.float32)
+
+        # Create and bind a Vertex Array Object
+        vao = glGenVertexArrays(1)
+        vbo = glGenBuffers(1)
+        glBindVertexArray(vao)
+        glBindBuffer(GL_ARRAY_BUFFER, vbo)
+        glBufferData(GL_ARRAY_BUFFER, quad.nbytes, quad, GL_STATIC_DRAW)
+
+        # Setup vertex attributes: position (location = 0)
+        glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 16, ctypes.c_void_p(0))
+        glEnableVertexAttribArray(0)
+
+        # Setup vertex attributes: texture coordinates (location = 1)
+        glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 16, ctypes.c_void_p(8))
+        glEnableVertexAttribArray(1)
+        return vao
+
+    def draw_image(self, tex, win_w, win_h, alpha):
+        glUseProgram(self.shader)
+        glBindVertexArray(self.vao)
+        # FIXME check if tex.id is None
+        glBindTexture(GL_TEXTURE_2D, tex.id)
+
+        # Calculate aspect ratios
+        img_aspect = tex.width / tex.height
+        win_aspect = win_w / win_h
+
+        # Calculate scaling factors to preserve image aspect ratio
+        if img_aspect > win_aspect:
+            sx = 1.0
+            sy = win_aspect / img_aspect
+        else:
+            sx = img_aspect / win_aspect
+            sy = 1.0
+
+        # Create transformation matrix for aspect-ratio-correct rendering
+        transform = np.array([
+            [sx, 0, 0, 0],
+            [0, sy, 0, 0],
+            [0,  0, 1, 0],
+            [0,  0, 0, 1],
+        ], dtype=np.float32)
+
+        # Pass transformation and alpha to the shader
+        glUniformMatrix4fv(self.uTransform, 1, GL_FALSE, transform)
+        glUniform1f(self.uAlpha, alpha)
+
+        # Draw the textured quad
+        glDrawArrays(GL_TRIANGLE_STRIP, 0, 4)
+
+    def draw_static(self, tex, win_w, win_h, alpha):
+        # Set the background color to black
+        glClearColor(0.0, 0.0, 0.0, 1.0)
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
+
+        self.draw_image(tex, win_w, win_h, alpha)
+
+        glutSwapBuffers()
+
+    def draw_transition(self, tex_start, tex_end, win_w, win_h, delta_time, transition_time, transition_duration, reversed):
+        assert self.transition, "No transition has been set"
+
+        # Set the background color to black
+        glClearColor(0.0, 0.0, 0.0, 1.0)
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
+
+        self.transition.draw(tex_start, tex_end, win_w, win_h, delta_time, transition_time, transition_duration, reversed)
+
+        glutSwapBuffers()
+
+
+class Transition(Protocol):
+    def __init__(self, renderer):
+        self.renderer = renderer
+
+    def draw(self, tex_start, tex_end, win_w, win_h, delta_time, transition_time, transition_duration, reversed):
+        pass
+
+
+class TransitionMix(Transition):
+    def draw(self, tex_start, tex_end, win_w, win_h, delta_time, transition_time, transition_duration, reversed):
+        # Update alpha value for fade effect
+        alpha = transition_time / transition_duration
+        if alpha > 1.0:
+            alpha = 1.0
+
+        # Draw the images on top of one another
+        self.renderer.draw_image(tex_start, win_w, win_h, 1 - alpha)  # TODO instead of decreasing alpha, draw transparent letterboxes
+        self.renderer.draw_image(tex_end,   win_w, win_h, alpha)